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You might mistake bilberries (Vaccinium myrtillus) for blueberries (V. corymbosum) in the wild. Both are small, dark blue berries that grow on woody shrubs. Since wild blueberries are smaller and have more intense flavor than their domestic counterparts, it might be hard to tell, since bilberries are also smaller and darker than domestic blueberries, but there are ways. We’ll get to that. More accurately known as common bilberries or blue whortleberries, these tasty tidbits also go by blaeberries, wimberries, and whortleberries, depending on where you live. Bilberry description Bilberries grow on small, deciduous bushes with many branching stems. They rarely grow more than a foot-and-a-half tall (45cm), but they can spread throughout an area via rhizomes, potentially making a lovely short hedge. Small, spear-shaped leaves are light green in summer and turn brilliant red in autumn. Flowers hang from thick stems in spring, and turn from white to pink as they mature. By summer, small, dark blue, slightly flattened fruits with crescent-shaped brown seeds appear. There are also red, red-spotted, white, and yellow fruits in some cases. How to grow bilberries Bilberry roots can grow up to 40 inches deep (1m), and these plants can live for up to 30 years, so choose your planting site carefully. Bilberries grow best in USDA Plant Hardiness Zones 3-7. They love cold winters, mild summers, and indirect sun. And they have specific chilling hour requirements (400-1,000 hours), depending on the variety and your microclimate, so choose accordingly. Where you live dictates when to plant. You can start your bilberries from seed or with certified pest- and disease-free bare root plants or rhizomes. They can also be started by cuttings and layering. Bilberry plants prefer loose, loamy, or sandy soil. Being short, wind damage isn’t a problem. Do you have a partially (or fully) shaded area of your yard? These plants prefer acidic soil (4.5-5.5pH), so they may enjoy being tucked under a pine tree for some long-term slow-release acidification. If you decide to install more than one bilberry plant, they should be spaced 18-24 inches (45-60cm) apart. You can also grow them in large containers. To plant bare root stock, dig a hole twice as wide as the root ball and just as deep. This allows you to spread out the roots, giving them free rein for their first weeks, and ensures that you install plants to the same depth they were before. Too deep and too shallow are both bad for your bilberries. You can mix some aged compost into the removed soil before you sprinkle it over the roots. Resist the urge to tamp the soil down. This damages root hairs and makes life difficult for your latest addition. Instead, simply water it well. Also known as mudding in, this eliminates air pockets and hydrates the roots, all without causing harm. Finally, mulch around, but not touching, your bilberry to stabilize soil temperature and conserve moisture. Do not overwater. Bilberry pests and diseases Drainage is important to bilberry plants. Soggy soil commonly sets the stage for root rot. And poor air flow can lead to leaf spot diseases, so avoid overhead watering. Aphids and birds are the most common pests of bilberries.
Raspberry ringspot (RRSV) is a viral disease that infects an odd assortment of plants. While raspberries, followed closely by strawberries and boysenberries, are vulnerable, cherry trees, members of the grape family (Vitis), and Narcissus can also be infected.
Either way, this is an important distinction because planting raspberries or strawberries near your grapevines, cherries, or adding a little springtime color with some daffodils, jonquils, or narcissus, can significantly increase the odds of your plants becoming infected and spreading this disease. Did you know that the raspberry ringspot virus (Nepovirus rubi) is a close relation to the tomato ringspot virus (N. lycopersici)? They are so closely related that raspberry plants can catch tomato ringspot. I don’t know if tomatoes can catch raspberry ringspot, but I wouldn’t be surprised. But it brings up an important point about raspberry plants. They are rugged once established. Very often, they will be infected with multiple diseases before we notice anything is wrong. It is the older, less virile plants that are more likely to catch raspberry ringspot. Once they catch it, however, it can spread. How to identify raspberry ringspot Like other ringspot diseases, the raspberry ringspot virus causes target-shaped, oval, or abstract rings that can appear on leaves or fruit, depending on the plant and virus involved. [Unfortunately, I could not find an image I could use.] Other symptoms include an overall failure to thrive and crumbly fruit. Managing raspberry ringspot Besides watching where you plant your raspberries, you can reduce the odds of ringspot by keeping wild brambles out of the area and only using certified pest- and disease-free stock. But the problem may already be in your soil. RRSV is carried by dagger nematodes. These tiny buggers move through the soil, spreading disease and mayhem in their wake. OK, it’s a very small mayhem, but you get the idea. Dagger nematodes have a reputation for being the most destructive of their species when it comes to plants. Unfortunately, they are hard to get rid of. While you can apply a nematicide (nematode poison), it won’t kill all of them. Any that are left can reproduce exponentially and asexually, so it’s an uphill battle. The only sure-fire way is to combine the nematicide with two years of leaving the area fallow, or unused. This will starve them out. Crop rotation can help, too. At this time, I am unaware of any resistant varieties, so keep your plants healthy by choosing varieties suited to your microclimate and ensuring they have everything they need to thrive. We’ve already talked about several different borer species, including the European corn borer, squash vine borer, and the raspberry crown borer. Today, we will look at more borer threats to your blackberry, boysenberry, dewberry, and raspberry plants. Cane borers Borers lay eggs in woody tissue. When the eggs hatch, larvae begin feeding and tunneling. This weakens the plant and increases the chance of other pests and diseases taking hold. Adult borers are most active during late spring through summer. There are three different species of cane borers: the raspberry cane borer, red-necked cane borer, and bronze cane borer. Bronze and red-necked borers are nearly identical in life cycle and behavior, while raspberry cane borers behave somewhat differently. All three are narrow-bodied beetles. Raspberry cane borers Raspberry cane borers (Oberea bimaculata) are also known as the raspberry root borers. Adults are approximately half an inch long (12mm), black with an orange thorax, and have two or three black dots (as seen above). They have long antennae. Adults feed on tender new cane tips, leaving behind scarred brown patches. They have a two-year life cycle. After feeding all summer, female raspberry cane beetles drill a double ring, about half an inch apart, around a cane or lateral shoot, girdling the stem, usually in the uppermost portion of the cane. Here, she deposits her eggs, where her offspring can develop in relative safety. This egg-laying causes the tips to wilt and turn black, so be on the lookout for that symptom. Once the eggs hatch, the larvae begin boring downward, in a slow march to the base of the plant, which they usually reach by fall. By the following summer, they have usually reached the crown, feeding and causing damage as they go. This can result in the death of the cane. Flat-headed borers Bronze and red-necked cane borers are also known as flat-headed borers, since their larval stages have flattened heads, similar to Pacific flathead borers. Bronze cane borers (Agrilus rubicola), also known as rose stem girdlers, are slightly smaller than other cane borers. Adults may only be one-quarter of an inch long (6mm) and are iridescent copper or bronze. Red-necked cane borers (Agrilus ruficollis) are often described as one of many jewel beetles due to their metallic exoskeleton. The wing covers (elytra) are black, and the area just behind the head (pronotum) is reddish orange. If you look closely, you can see a divot at the base of the head. These beetles are one-quarter to one-half an inch (6–12mm) long. You can often see adults feeding on the edges (margins) of leaves on warm, sunny days. If you are quick, you can knock them into a container of soapy water to eliminate them. Adult females lay whitish, scaly eggs on and in the bark of new cane growth, usually in late spring, near the lower portion of the cane. Newly hatched larvae frequently enter the bark at the axil of a leaf stem, spiral the sapwood a few times before heading deeper, into the hardwood, and then the pith. At this stage, the larvae are full-grown and single-minded, heading straight down to the crown where they overwinter and pupate. All those early twists and turns create symmetrical galls. These galls can be one-half to three inches long and often exhibit slits. How to manage cane borers
First, monitor canes for signs of blackened or brown cane tips, dieback, galls, or wilting. If symptoms occur, you can try to save the cane by making a cut two or three inches below the affected area, removing and destroying the infected portion. Continue to monitor those trimmed canes for signs of speedier-than-normal larvae who may have gotten below where you made your cut. It is often easier to completely remove affected canes. Keeping your garden and landscape free of wild brambles can help reduce the chance of cane borers finding your berries. The insecticides used by commercial growers against adult borers are rather nasty and not recommended for the home gardener (or anywhere, for that matter). If you garden, you’ve heard of peat moss. But what is it, really? And what role does it play in our gardens? Let’s find out! Peat v. peat moss
First, peat and peat moss are not the same thing. Peat moss is a type of moss. Actually, several types. And peat is a conglomeration of partially decayed organic matter that makes up bogs. Peat moss is a major component of peat, but not always. Peat moss, the plant Peat moss also goes by the name sphagnum. There are nearly 400 species of sphagnum moss. It can grow on pretty much anything. Sphagnum has one rather odd characteristic: it alternates living cells with dead cells. Those dead cells are used to store water. Using this method, some mosses can absorb up to 20 times their own weight in water, which is why it is so popular in gardens. How we use peat moss Being able to hold so much water, peat moss helps keep our plants hydrated. Due to this characteristic, it is a common ingredient in potting soil and when growing microgreens. It is advertised as a soil amendment that improves soil structure and nutrient availability. You can overwinter tubers in a bucket of peat moss. Root cuttings are often stored in moist peat moss. Contrary to popular opinion, adding peat moss (or pine needles) to your soil does not effectively alter its pH. That only works in laboratory settings and large-scale commercial enterprises. Peat moss is used as fuel, in floral arrangements, and in crafts. Dried sphagnum moss has been used as a wound dressing. Note that peat moss can contain the fungus Sporothrix schenckii, which, according to the Centers for Disease Control and Prevention, can infect people with rose handler’s disease, or sporotrichosis, a potentially serious condition. As always, wash your hands after working with peat moss or in the garden. But there is another problem associated with peat moss. The problem with peat moss Peat moss is harvested from peat bogs. Peat bogs cover approximately 3% of the Earth’s surface, store significant amounts of carbon dioxide, and are home to countless wildlife species. Technically, peat bogs and peat moss are renewable resources. Some companies harvest peat responsibly, while others do not. [How can we tell by looking at a bag in the store?] It takes one year to generate one millimeter of peat on average. And we are using it at ever-increasing rates. Instead of using peat moss to improve your soil, opt for more sustainable materials, such as aged compost, wood chips, coconut coir, and even shredded paper. These materials can be added to potting soil or used to top dress a garden bed without the drawbacks associated with peat moss. Mid-winter can be a tough time for growing fresh greens at home if you live in an area with cold temperatures, ice, and snow. But microgreens are one way to get delicious, healthful greens at any time of year What are microgreens? Microgreens are halfway between sprouts and baby greens in the plant development process. Where sprouts are germinated (or partially germinated) seeds without any real leaf development, and baby greens are miniature versions of adult plants, microgreens are harvested just after the cotyledons and first true leaves have appeared, usually when they are two or three inches tall. They are a fast-growing way to add bright freshness to your diet, even in the middle of winter. While they may be small, microgreens can contain 4–40 times the level of nutrients found in their adult counterparts, according to the USDA Agricultural Research Service and the University of Maryland. In that study, broccoli microgreens were found to contain sulforaphane, known to block DNA mutations that can lead to cancer, as well as compounds that neutralize toxins and reduce inflammation. These little plants are nutritional powerhouses and easier to digest than full-sized greens. What are popular microgreens?
Nearly all salad greens, vegetables, herbs, and edible flowers can be grown as microgreens. Below is an exhaustive list of edible plants that can be grown as microgreens, grouped by plant family. Some of them may surprise you!
NOTE: Plants with an asterisk (*) have both edible and non-edible varieties. It is important to know which ones you are working with, so do your homework! Did you know that, unlike most microgreens, corn seeds grown in the dark are sweet, while those exposed to light taste bitter. Weird, eh? And, there are some plants you should never grow as microgreens. This group is the nightshade family. As much as we love the eggplants, peppers, potatoes, and tomatoes we grow, those stems and leaves are toxic and should not be eaten. How to grow microgreens Your microgreens can easily be grown on a windowsill, outside, or in a greenhouse. They can also be grown hydroponically, but do not fertilize your microgreens. They don’t need it, and it can make them taste bad. Start with shallow trays, at least half an inch deep, with drainage holes. You can also use ceramic planter saucers. If you are reusing a container, sterilize it first to prevent the spread of disease. Microgreens are gregarious plants and prefer not to be grown in the solitary confinement of egg cartons or individual pots. Next, add a shallow layer of potting soil or other growing medium, such as peat moss or coconut coir. Microgreens are an excellent way to use up those half-filled seed packets from the previous growing season. Just be sure to use certified pest- and disease-free seeds. You can either scatter the seeds over the top of the soil or plant them in tidy rows, if you have that much patience. Press the seeds gently into the soil to ensure good contact. Mist the seeds regularly until they germinate, keeping the soil moist but not soggy. And watch for mold and fungal disease. Your microgreens will grow best with plenty of sunlight. Problems with growing microgreens The biggest problem associated with growing micrograms is moisture. The seeds need that moisture to germinate, but all that wetness can lead to fungal diseases, such as damping off. This is especially common when temperatures are above 68°F (20°C). Ensuring good drainage and allowing the surfaces of leaves and stems to dry between waterings can help prevent disease. If necessary, you may want to place a small fan near your micrograms. This will help them dry, and it will also strengthen their little stems (thigmomorphogenesis). If you want a pro’s perspective, you can track down the FDA’s Guidance for Industry: Reducing Microbial Food Safety Hazards for Sprouted Seeds (FDA 1999). Harvesting microgreens Your microgreens are ready to harvest in as little as 10 to 25 days, depending on the species. Microgreens are harvested when they are 2 or 3 inches tall. The cotyledons (seed leaves) will be fully open, and the first two or three true leaves may be partially or fully developed. Microgreens are cut, often with scissors, just above the soil line. The remaining root system will slowly decompose, providing nutrients for important soil microorganisms and neighboring plants. As you harvest your microgreens, simply add more seeds to the soil to maintain a sustainable supply of delicious microgreens. Microgreens can add color, texture, flavor, and good nutrition to your omelettes, salads, sandwiches, and smoothies, and they can make your windowsill far more productive. Also known as the Western raspberry fruitworm, Byturus unicolor is the US counterpart to the north-central European raspberry beetle (B. tomentosus). The American raspberry beetle is something else entirely. As their name suggests, these pests will feed on your raspberries, but boysenberries, loganberries, salmonberries, and thimbleberries are not exempt. Raspberry fruitworms are found throughout Central and North America. To be honest, fruitworm beetles don’t look like much of a threat to anything, but their offspring can be something else altogether. Raspberry fruitworm identification Adult fruitworm beetles are only 0.16 to 0.19 inches long (4-5mm), so you could fit three or four of them across the face of an American dime. They are yellowish-brown with tiny hairs. Raspberry fruitworm larvae are twice as long as their parents. They are white underneath with light brown segments on top and darker brown lines along the center. Fruitworm larvae get bigger than their parents by eating your young raspberries. But the problem starts much earlier than that. Raspberry fruitworm lifecycle Adult fruitworm beetles spend the winter underground or hidden under leaves, protected against the elements. In spring, they emerge and start eating young raspberry leaves and flower buds. They start close to the ground and work their way up the canes to be closer to developing flower buds. Fruitworm beetles prefer feeding on the tissue found between the veins of new, unfolded leaves. This skeletonization is a clue. After mating, females lay more than 100 eggs on and near developing flower buds. Eggs hatch about the same time fruit is developing. The larvae burrow into the fruit, out of sight and safe from predators, where they feed for a month or so before dropping to the ground to pupate in the soil and begin the cycle again. All this feeding and burrowing can leave your raspberry harvest looking pretty meager. And there’s no guarantee that that raspberry you’re about to pop in your mouth doesn’t contain a guest. Ew! Raspberry fruitworm management The first step in reducing fruitworm damage is to monitor your plants regularly, as soon as new growth starts in the spring. Look for signs of adult and larval feeding. Handpicking adult beetles before they start laying eggs is much easier than dealing with a bigger problem later on. These beetles are most active in early evening, so that’s the best time to look for them. After removing beetles from your plants, simply drop them in a container of soapy water for chemical-free control. You can also use sticky traps near your raspberry plants to monitor for these and other pests. Ladybugs and lacewings are your allies in this battle, so make sure your garden is welcoming and free from indiscriminate chemicals. Fruitworms are more of a problem when weeds and wild blackberries are present, so keeping the area around your canes tidy and clean can help prevent the problem. Serious infestations may call for applications of spinosad or Bacillus thuringiensis (Bt). There are several types of Bt. To deal with fruitworms, you will need BtK, which can be found at local garden supply stores. This is best done during warm evenings while the plants are in the flowering stage. Follow package directions carefully and do not spray open flowers. After harvesting your raspberry crop, rake the area around the canes lightly to make life more difficult for overwintering beetles. If you have chickens, let them have the run of the area for a few days. Hens can be powerful pest control, and they are fun to watch. Fresh-from-the-garden raspberries are a real treat. Once canes are established, they can be relatively maintenance-free. But if you happen to notice that some of your raspberry leaves are starting to crinkle, curl, or change color, you may have a problem.
There are several reasons raspberry leaves start curling. Aphid, leafroller, leafhopper, and psyllid feeding can cause leaf curling, as well as chemical overspray and some viral diseases. Raspberry leaf curl is a viral disease carried by aphids. Symptoms of raspberry leaf curl At first, there are no symptoms. This is a slow-moving disease. You will eventually see mild downward leaf curling at the tips. The next year, you will see more pronounced symptoms. As the virus gets serious about reproducing inside the phloem tissue of your plants, canes will become branched, brittle, stunted, or develop into a rosette. Fruits will be small, deformed, and crumbly. Leaves of infected red raspberry plants will turn yellow, while black raspberry leaves turn a dark, greasy green. In both cases, the leaves on young and old canes will curl downward. [Leafhopper feeding causes upward curling.] Infected plants are highly susceptible to winter damage. Managing raspberry leaf curl Unfortunately, there is no cure for raspberry leaf curl. It may take two or three years, but infected plants will die. The only thing you can do once a plant is infected with raspberry leaf curl is remove it. Double-bag and trash infected plants or burn them if you have a fire pit going anyway. As you cut away infected canes, be sure to disinfect your pruners between each cut to prevent the spread of disease. To avoid raspberry leaf curl in the first place, install certified pest- and disease-free plants. If you have any wild brambles growing nearby, you may want to remove them. You can monitor for aphids using yellow sticky sheets, and insecticidal soap sprays can help keep aphid populations in check. Other plants susceptible to raspberry leaf curl include purple raspberries and wineberries, Himalaya blackberries, Pacific coast trailing blackberries, and wild blackberries. Tropical black raspberries, ‘Lucretia’ dewberries, and Alpine strawberries may also be vulnerable to this disease. As of 2023, raspberry leaf curl disease was predominantly found in Canada and northern-tier US states. Of course, high mobility rates and changing climates can make new areas appealing to the small raspberry aphid (Aphis rubicola), responsible for spreading the disease. Flower mites may be the fastest living things on Earth. But you wouldn’t know it by looking at them. And they don’t exactly run. But they sure do move!
It’s easy to see the big things in your garden: trees, shrubs, vines, and raised beds. And we know there are countless tiny things in our gardens, as well. But flower mites are pretty unique, even at half the size of a grain of salt. These nectar and pollen eaters hitch rides from one flower to the next with hummingbirds in a behavior known as phoresy. We used to think that flower mites ran up a bird’s beak and grabbed hold of their host’s nostrils for the flight from one flower to another. We now know that the electrostatic field created by the motion of a hummingbird’s wings helps propel those tiny mites, much like the sock that sticks to a blanket coming out of the dryer. Note: Research by Carlos Garcia-Robledo has shown that different flower mite species are attracted to specific frequencies related to the geometry, size, and vibration of their host. It’s a crazy world out there! However they do it, mites also hop onto the bats, bees, beetles, butterflies, and moths that frequent your garden. As their ride pulls up to a flower, mites often have only a split second to decide if the current flower can feed them. Guess wrong and die. [You can see some amazing photos at the Audubon website.] There are several different flower mite species, including Proctolaelaps, Rhinoseius, and Tropicoiseus. It should come as no surprise that flower mite dietary preferences tend to match their ride. Hummingbird flower mites prefer plants in the blueberry, coffee, ginger, onion, and pineapple families, and these are all big favorites of hummingbirds. You can usually identify mite feeding with a hand lens after noticing leaf blistering, bronzing, galls, and stippling. Some flower mites have a one-track mind. They feed on a single plant species all year. This is called monophagy. Other mites have a broader menu, following the bloom cycle of several flower species. This is called polyphagy. But how much nectar do flower mites eat? Does it really make a difference? I mean, these creatures are very small. It turns out that the answer is yes. Sort of. Nectar attracts pollinators and protectors. With less nectar, we would expect there to be less food for those pollinators and protectors, resulting in smaller harvests. And in some cases, we’d be right. According to one study, excluding flower mites increased the availability of nectar by up to 49%! That’s huge in the world of nectar feeders. One would expect that heavy mite feeding would negatively impact the health of local pollinators by reducing their food supply. But the net result might surprise you. Sometimes, flower mite feeding reduces pollination, resulting in smaller crops. But not always. In some cases, flowers respond by producing more nectar. In other cases, pollinators work harder, visiting more flowers. By doing so, they actually increase pollination rates. We have already discussed bulb mites, citrus bud mites, dryberry mites, European red mites, fig mites, spider mites, and more. For the most part, they are microscopic arachnids. Some are worse than others. While flower mites do not technically carry plant diseases, they do carry the viruses and phytoplasmas responsible for aster yellows, various leaf spot diseases, and potato virus Y. The bottom line on mites: how you respond to them depends on your tolerance level. If your plants are healthy, you don’t need to do anything about flower mites. If your plants are prone to the diseases mentioned above, you can spray the affected areas with insecticidal soaps or horticultural oil. We hear the word carbon thrown around a lot: carbon copy, carbon footprint, carbon life forms.
But what is carbon, and what does it have to do with gardening? Carbon is an element found in all living things. In fact, carbon is second only to oxygen in our bodies. Carbon can take many forms. It can be the graphite in your pencil, the diamond on a wedding ring, a gas, or a liquid. It is also found in the compost, manure, and plants in your garden. That adaptability, paired with its ability to bond easily with other atoms and molecules, is probably why we find it almost everywhere, including in our garden. How plants use carbon Carbon is fundamental to life as we know it. Plants pull carbon dioxide from the air to use in photosynthesis in a process called the Calvin cycle. Carbon is also used to make cellulose. Cellulose is what gives plant cell walls their structure. Combined with lignin, pectin, and a few other materials, carbon is what holds trees and plant stems upright. Did you know that the cotton fibers in your T-shirt are one of the purest forms of cellulose? I didn’t either. Carbon in the soil Soil carbon is a term used to describe the amount of solid carbon found in soil. That carbon comes from inorganic carbonate minerals. It also comes from all the carbon-based life forms living in and on the soil, like beetles, microorganisms, and worms. When those creatures poop or die, their carbon becomes part of the soil organic matter that plant roots call home. The same is true of neighboring plants. As they decompose, their carbon is stored in the soil. Carbon improves soil structure and keeps plants healthy and productive. It’s been that way for millions of years. Until recently. Commercial farming and deforestation have created problems regarding soil carbon. The use of heavy machinery and excess digging kicks carbon into the atmosphere as carbon dioxide, contributing to climate change and reducing soil carbon levels. Reduced carbon levels also impact the effectiveness of nitrogen fertilizers. Or maybe it’s the other way around. Research conducted at the University of Illinois at Urbana-Champaign discovered that farmed soils have shown a significant reduction in soil carbon levels since farmers started applying synthetic nitrogen fertilizers in the mid-1950s. The more nitrogen that was added, the more carbon was lost from the soil. Fertilizers cost money. We don’t yet know if adding the fertilizer makes plants grow more quickly than the soil carbon can be replaced, or if it is something else. Too much nitrogen creates nitrogen pollution, as well. For me, this stresses the importance of lab-based soil tests. Our plants need nitrogen, but too much of a good thing can easily become a bad thing. And lost soil organic matter translates into lost water. Healthy soil needs carbon, microorganisms, and time to process and store water effectively. Putting carbon back into the soil is not a simple matter of burying some charcoal or using biochar. These things are delicate chemical interactions. How to retain soil carbon We can help our garden soil retain the carbon our plants need and reduce the amount of carbon lost to the atmosphere with the following tips:
We can improve soil health and soil carbon levels with just a little effort. I think it’s worth it. Leaf drop is a type of abscission. It can be a normal part of a plant’s life, or it can be a clue to a problem.
As plants age, they often lose older leaves. That’s normal. As days shorten and temperatures drop, deciduous plants break down the chlorophyll in their leaves before dropping them. That’s normal, too. But sometimes leaf drop is a plant’s way of telling us something is wrong. Below is a list of the most common causes of abnormal leaf drop:
The best way to keep your plants healthy is to start with species suited to your microclimate and USDA Plant Hardiness Zone. Then, place them where they will get the sun exposure (and any wind or traffic protection) they need. Monitor your plants regularly for signs of pests or disease. It’s a lot easier to nip problems in the proverbial bud if they are caught early. And get your soil tested every few years. It’s the only way to see what your plants have on their menu. The Number One cause of abnormal leaf drop is water. Too much water can drown your plants. It can also make them more susceptible to pests and diseases, and generally make them miserable. Leaf drop is a symptom of too much (or too little) water. Give your plants the water they need, and no more. An inexpensive moisture meter can help you prevent overwatering. The easiest rule of thumb for most containerized plants is to wait until the soil starts pulling away from the edges of the pot before watering. If leaves are falling off your plant at the wrong time of year, use these clues to help you find out why. Once you know the cause, you can find a solution to your plant’s problem. Leaves are critical to plant health. Healthy leaves perform photosynthesis. This is where plants make sugar from sunlight. Healthy leaves also help plants get rid of excess water in a process called guttation. And leaves make shade, preventing sunburn (ours and theirs). But leaves are easily damaged. We prune them, bump into them, and neglect them. But that’s not all. Leaves are damaged from the inside by disease and malnutrition, and they can be chewed on, sucked dry, or beaten senseless by external forces. Note: When you spot leaf damage, it is a good idea to isolate the plant, if possible. Then, as you read through this information, use the links for more detailed information on each condition, disease, pest, and effective treatments in each case. Recognizing the source of the problem will help you find a solution. Identify the insects you see so that you will know if they are helpful or harmful. And decide on your tolerance level for plant disease and other garden problems. Keeping your plants healthy goes a long way toward reducing your workload and improving your harvests. Let’s start with diseases. Diseases that cause leaf damage Leaf problems are often a gardener’s first sign of disease. These diseases can be bacterial, fungal, or viral, and each has unique characteristics that can help you identify and treat the problem. Bacterial diseases often start as water-soaked lesions on leaves that dry out and fall away, creating shothole patterns. Those lesions commonly have yellow halos. Wilting is another common symptom of bacterial disease. Some common bacterial diseases that cause leaf damage include the following: Fungal diseases often appear as angular lesions or bullseye-shaped spots on leaves that spread quickly. These spots have clearly defined edges. Fungal diseases also appear as tiny black dots, and you may be able to see mycelium threads. Affected leaves may become thick or rubbery. Some fungal diseases that cause leaf damage in your garden include the following: Viral diseases block the flow of fluids inside our plants. Viral diseases appear as irregular patches of mottling or mosaic patterns without clearly defined edges or yellow streaking. Infected leaves often curl or twist. Affected leaves may develop purple veins. Wilting can also occur. Viral diseases tend to progress slowly. Viral diseases that cause leaf damage include the following:
Where do leaf-damaging diseases come from? Leaf-damaging plant diseases can be carried by a variety of pests, including aphids, beetles, flies, gnats, leafhoppers, moths, nematodes, psyllids, thrips, weevils, and whiteflies are common disease vectors. Diseases that cause leaf damage can also be carried on neighboring plants, old cigarette butts, our shoes, garden tools, and the wind. How do you know what the problem is? Some diseases are easy to identify. The red, rubbery, wrinkled leaves of peach leaf curl are unmistakable. But other causes share symptoms. For example, mosaics usually indicate a viral disease but can also mean your plants are suffering from chemical overspray. You will have to take other factors into consideration to sort things out. If you need more detailed information, check out my book What’s Growing Wrong? Or contact me, and we can sort it out together. Leaf damage caused by suckers Many pests damage our plant leaves by sucking out sap. This is most often done by invertebrates. Invertebrates do not have backbones. Being spineless in this case does not imply that these creatures lack courage. On the contrary, they tend to be highly flexible, adaptable, and potentially destructive to your garden. This group includes insects, sowbugs, snails, spiders, and more. Did you know that 97% of all animal species are invertebrates? I didn’t either. Common sucking pests include the following: Leaf damage caused by chewers You can usually tell when something has been chewing on your garden plants. If you see ragged leaf edges, it’s probably herbivore feeding, while smoother edges and skeletonization usually indicate insect and other invertebrate feeding. Common leaf chewing pests include the following: Chipmunks, deer, groundhogs, livestock, mice, rabbits, rats, squirrels, and occasionally voles will also cause leaf damage. Nutrient disorders that cause leaf damage Healthy leaves are deep green, to one degree or another. It depends on the plant species. When things start going wrong, they may turn into paler versions of themselves. This yellowing, or chlorosis, can be due to nitrogen or potassium deficiencies. Other symptoms (and causes) of nutrient-based leaf damage include the following:
The best way to prevent and monitor for nutrient disorders is with a lab-based soil test every 3-5 years. Don’t let the word “lab” scare you off. These tests are inexpensive and incredibly helpful. Do it once, and you’ll see what I mean!
Other causes of leaf damage Leaf damage isn’t limited to people, pests, and diseases. There are environmental factors to consider. Sometimes you can fix these problems, and sometimes you can’t. The most common environmental factors that cause leaf damage include the following: When diagnosing leaf damage, start with the specific type of plant. What species is it? Then consider its developmental stage. Is it a seedling, flowering, fruiting, or preparing for winter? Symptoms will appear differently as the year progresses and on different plant species. And this is why it is so important to monitor your plants. I like to consider myself something of a detective when it comes to sorting out leaf damage and other garden issues. Good gardeners are always on the lookout for clues on the health of their plants. And leaves are nearly always the best place to start looking. For me, the word bramble evokes images from fairy tale stories of gnomes, giants, and hidden cottages. But bramble fruits can be a delicious addition to your landscape, producing abundant fruit with minimal effort for decades. What are bramble fruits? You might be surprised to learn that bramble fruits are not berries, botanically speaking. Instead, they are aggregates of druplets that grow on woody canes. Most of them feature sharp prickles, like those found on roses. All bramble fruits are members of the Rubus genus. Blackberries and raspberries are common bramble fruits, but there are other brambles you might grow. Other members of this clan include bristleberries, dewberries, salmonberries, wineberries, and youngberries, as well as hybrids such as boysenberries, loganberries, marionberries, nessberries, and tayberries. Researchers are still debating how to classify these prolific fruit-producers, but we can leave the molecular science to them while we enjoy freshly picked fruit from our yard. How to grow bramble fruits Brambles have perennial roots and crowns that grow new canes each year. Most brambles are biennial hermaphrodites. This means they are self-pollinating and produce fruit the second year of each cane’s life.
Those growth characteristics make it easy to start new brambles from old canes. Simply lay the cane on some moist soil, and roots will emerge. Most brambles prefer morning sun and protection from scorching afternoon sunlight. Generally speaking, bramble fruits grow best in USDA Plant Hardiness Zones 4 through 9.
The spreading growth habits of most brambles have made them popular throughout human history in pleaching and coppicing. Coppicing is a simple practice of repeatedly cutting woody plants close to the ground to acquire thin, straight, flexible wood for basket-making and other applications. Pleaching refers to weaving dead branches among living branches to create a hedge or barrier. It also describes the method by which talented tree trainers create amazing works of art by bending and shaping living trees and shrubs. Brambles have also been used as defensive plants to keep enemies and potential thieves at bay with those sharp prickles. Despite how quickly brambles grow and how productive they can be, they do face some problems in terms of pests and diseases. Pests and diseases of bramble fruits These plants are rugged, but they are susceptible to the following garden pests:
Diseases to watch for in your bramble patch include the following:
Many of these pests and diseases can be prevented by properly spacing plants, mulching around canes without touching them, regularly inspecting the canes for signs of problems, and applying horticultural oils during the delayed dormant period. While bramble fruits pose some challenges, they can provide decades of fresh summer fruit and year-round supplies of delicious jams, jellies, and gifts from your garden. Lychees may have been cultivated in Asia as early as 2000 BC. The sweet-tart, floral fruits are a good reason to give these evergreen members of the soapnut family (Sapindus) a try. Lychee trees (Litchi chinensis) can be grown in USDA Plant Hardiness Zones 10-11, making Hawaii, Florida, southern California, and Texas great places for lychee trees. There are three different types of lychee, and hundreds of cultivars, but none of them take well to container gardening. They can’t handle frost or temperatures below 25°F (-4°C). Despite their need for warmth, lychees need at least 100 chill hours before they can produce fruit. As tropical trees, lychee prefer slightly acidic, moist soil in a location with full sun and protection from wind. They tend to grow tall and rather cylindrical because fighting for sunlight in the jungle requires arrow-like speed in many cases. Fragrant flowers grow in clusters, but it is the red, bumpy fruits that justify your landscape real estate. Lychee trees can be pruned to a much more manageable size. They really add character to a landscape. Lychee fruits are arils. Arils are fleshy outgrowths that fully or partially cover a seed. The lovely red netting over nutmegs, called mace, is an aril. Arils are also called false fruits, but there is nothing false about the refreshing sweetness of lychee fruit. Do not eat the seeds; they can cause hypoglycemia in some cases. Instead, peel your ripe lychees and savor the fleshy white treat inside You can start a lychee tree by air layering. Simply take a young, healthy twig and cover the cut end with growing medium, such as peat, and wrap the medium with plastic. Before long, roots will form, and you can remove the plastic and place your baby lychee tree in its forever location.
Spanish limes (Melicoccus bijugatus) are edible, tropical sweet-tart fruits from the soapnut family. The Greek and Latin parts of its name translate as honey seed. Native to northern South America, the fruit is a drupe. Drupes are single stony seeds covered by fleshy fruits, like an apricot.
You can grow Spanish lime trees in USDA Hardiness Zones 10A to 11. You can also grow them in containers, which can be brought indoors or moved to more protected locations if your winters are less than tropical. These trees prefer full sun and moist, well-drained, slightly acidic soil (pH 6.0–6.5). Fragrant flowers appear in late spring to early summer. They are white with four petals and eight stamens. The trees are slow and steady growers.
Fruits start out yellow, then turn green and develop a pink blush as they ripen. Mature fruits are approximately two inches (5 cm) in diameter. The skin is somewhat spiky, so gloves are recommended during harvest. Common pests of Spanish limes include aphids, citrus leaf miners, and scale insects. You can use insecticidal soap or neem oil to control those pests. The only disease I saw mentioned was citrus greening disease, also known as huanglongbing. These fruits do not store well unless you can them, so eat them as they ripen. They can be used in margaritas, pies, salsa, and smoothies. See if you have a sunny spot for this lush, productive shade tree in your landscape for planting next spring. When I first saw the name raspberry horntail, my mind conjured up a ripe, red raspberry with a ram’s horn tail. Of course, raspberry horntails are nothing like that, but it was a fun image. The truth about these parasitic wasps is less fun. Raspberry horntails are a type of sawfly. Sawflies get their name from the saw-like ovipositor used by females to insert eggs under a plant’s skin. These pests prefer raspberries, but they will also feed on blackberries, other bramble fruits, and roses. You may run into some confusion when talking with others about raspberry horntails (Phylloecus (formerly Hartigia) cressonii) because there are raspberry cane borers (Oberea bimaculate), which are frequently called raspberry horntails or raspberry cane girdlers. Or your friend may be talking about raspberry sawflies (Monophadnoides rubi). Yes, it can be confusing sorting all this out sometimes, but photos can help. [Unfortunately, I could not find an available image of a female raspberry horntail.] Let’s start with symptoms. As new canes form, typically in spring, raspberry horntails lay their eggs under the surface. If you look closely, you may see small, round, discolored areas where the eggs were laid. If you can get to one, raspberry horntail eggs do not look like what you might expect. They are white, oblong, and they have a flattened, curved point at one end. When those eggs hatch, young larvae spiral upward inside the canes where they feed just below the cambium layer. This causes cane tip wilting. It also weakens the plant and can cause dieback. Infested canes may also twist or become crooked. Infested canes are more susceptible to breaking, frost damage, and other pests and diseases. As larvae grow, they turn around and head lower in the cane, feeding on both the inner cambium layer and the pith. This significantly reduces flower and fruit production. Eventually, the larvae create silk-lined apartments in which they overwinter. As temperatures rise in spring, larvae pupate and then emerge as adults. But it is the larvae who cause the damage. Raspberry horntail larvae are white and can be up to one inch long. They have hard brown heads and a tiny spike on the other end. Pupae are slightly smaller and tan. Adults are only half the size of their fully grown larvae, with narrow bodies and long antennae. Males tend to be black with orange and yellow markings, while adult females are gold to orange with black spots. If you suspect a raspberry horntail problem, prune about six inches below the cane tip and slice the removed bit in half lengthwise. If it looks like the infestation extends lower than what you have in your hand, remove more of the cane.
These pests are not generally a serious problem, but it pays to regularly inspect your raspberry plants. Bag and dispose of any infested material in the trash. Do not add it to your compost pile. Unless you can time applications to coincide perfectly with egg-laying in your area, insecticides are not recommended, since larvae and pupae are protected inside the cane, and adults simply fly away. Keeping your raspberry plants healthy is always your first line of defense. As kids, we called them helicopters. Double- and single-winged seed pods fell from trees by the thousands each autumn, and we would gleefully fling them into the air to watch them spin earthward. My grandson does the same thing now, but I think he prefers calling them whirlybirds. Looking closely, you may be surprised to see how much samaras look like insect wings. They probably evolved in a similar manner for the same reasons. Botanically, they are called samaras. Samaras are a type of fruit, called achenes. The seeds we blew from ripe dandelions are also achenes. Achenes are indehiscent, simple dry fruits. [Indehiscent means they do not split open the way pea pods do.] Samaras are notable for their papery wings. You can use the number of wings and the position of the seed to help identify the tree in question. If the seed is found in the middle of a pair of wings, it is likely to be bushwillow, elm, or hoptree. If the seed is found at one end, it is ash, mahogany, or maple. British sycamores (Acer pseudoplatanus) may have three or four wings.
Sweet, juicy, and generally easy to grow, berries are a great reason to garden. We have already discussed blackberries, boysenberries, loganberries, raspberries, and youngberries, but dewberries are a little different. Unlike those other berries, most spiny dewberry canes grow along the ground, sending out roots as they go. Because they spread so easily, they are sometimes referred to as beneficial weeds. There are several species of dewberry found throughout the Northern Hemisphere. There are two main categories of dewberry: European (Rubus Caesii) and American (R. Flagellares). Within the American section, there are several species to choose from, all of which are native to the region east of the Rocky Mountains. Dewberries can be grown in USDA Plant Hardiness Zones 5–10 and tend to prefer coastal, sandy areas with temperatures between 50°F and 70°F (10°C to 21°C). Some species are more upright than others. Fragrant white flowers bloom from late winter to early spring and turn into small, green berries. As the berries ripen, they change from red to black or purple by mid to late spring. These are some of the first berries you can harvest each year. When they are dark and fully ripe, they hold tightly to the plant and can be easily squashed, so handle them carefully when picking.
Be sure to consider their growth habits when selecting a site for dewberries. They can easily turn into a thicket that can be challenging to manage. You can grow dewberries from seeds or cuttings. Plants should be installed in early spring and spaced three feet apart. They are best trained up a trellis, protected from strong winds. They prefer full sun but can also be grown in partial shade. This is especially true in areas with scorching hot summer temperatures. It takes a few years for dewberries to start producing fruit, but once they do, you will probably have a lifetime supply. Dewberries can also be grown in large containers. In either case, they will benefit from top dressings of aged compost. Aphids, cane borers, dewberry mites, leaf beetles, peach blossom moths, and spider mites may be attracted to your dewberries. So will chipmunks, deer, fox squirrels, raccoons, white-footed mice, and many other mammals. But these plants are rugged. Overwatering and poor drainage are more likely to cause fungal problems, such as blight, downy mildew, fruit, root, and stem rots. As with other bramble fruits, remove spent canes with a pair of high-quality bypass pruners to improve air flow and promote new growth. Did you know that boysenberries are a cross between loganberries and dewberries? Now you know. Is it a cucumber or something else entirely? Also known as snake cucumbers, snake melons, and yard-long cucumbers, Armenian cucumbers (Cucumis melo var. flexuosus) are more muskmelon (C. melo) than cuke (C. sativus). These are not to be confused with another long member of the melon family, serpent gourds, which also taste like cucumber. Long, skinny, and ridged, Armenian cucumbers taste like common cucumbers, but their skin is thinner and lighter than grocery store cucumbers. There are three types of Armenian cucumber that I know of: regular, striped, and dark green. In each case, these crisp fruits can grow three feet (90 cm) long and they can handle all the heat your summers can dish out. You can start Armenian cucumbers from seed any time from late winter through early summer, as long as soil temperatures are consistently above 65°F (18°C). As far as these plants are concerned, hotter is better. And they don’t turn bitter the way true cucumbers do.
Seeds should be planted one inch deep, and plants should be at least 12” apart. You can allow the vines to stay on the ground or train them up a trellis. Your Armenian cucumbers need full sun, but they will still produce abundant crops even if they get some afternoon shade. Because these plants are susceptible to the same problems as other cucurbits, crop rotation is an excellent preventative measure. Aphids, cucumber beetles, fruit flies, pill bugs, and spider mites are the most common pests of Armenian cucumbers. Overhead watering Armenian cucumbers often leads to anthracnose, black rot, blight, downy mildew, powdery mildew, root rot, and rust. Instead, water deeply using furrow irrigation and allow plants to dry out between waterings. If your Armenian cucumbers get away from you and grow extra-large, you may cut into them and discover the mucilage around the seeds has turned orangish and the flesh may taste less cucumber-like. You can still eat it, but this is the best time to select seeds for saving for next year.
Young fruits are dark to medium green with light green, longitudinal stripes. As the fruit matures, the blossom end and flesh begin to turn red and bitter. This is when serpent gourds are used as a tomato replacement. In some regions they are called snake tomatoes. The leaves, shoots, and tendrils of serpent gourds are also edible and commonly eaten as greens. Seeds should be planted one inch deep, and plants should be at least 12” apart. You can allow the vines to stay on the ground, but they perform best when trained up a trellis. The fruits are very impressive, hanging overhead. You may want to intercrop your serpent gourds with red noodle beans for an especially impressive display.
Your serpent gourds need full sun, but a little afternoon shade is fine. Are plants less nutritious these days?
It ends up, they are. Before we learn about that, what determines how nutritious a piece of fruit or a salad is in the first place? The nutritional value or mineral content of food crops is dependent on the following factors:
Several decades ago, our fruits and vegetables contained significantly more nutrients than they do today. We have traded quality for quantity, becoming overfed and undernourished, something we cannot continue indefinitely. So, how did it happen? And what can we do about it? Primarily, it comes down to soil depletion. Modern agriculture grows so much, so fast that the soil does not have time to recover. We may add nitrogen, phosphorus, potassium, and secondary nutrients, but soil health isn't that simple. There is an astounding chemical, electrical, and biological dance that happens underground to make plants (and people) healthy. The more chemicals we use, the less likely the soil is to produce healthy crops. A study published in 2004 in the Journal of the American College of Nutrition at the University of Texas at Austin noted “reliable declines” of the nutrients in our food plants over the previous 50 years. Donald Davis and his team pointed out that produce has been grown with an eye for appearance, disease and pest resistance, productivity, and shelf stability over nutrition for a long time. For too long, in my opinion. Other studies have demonstrated similar reductions in nutritional value:
As noted in the Scientific American article Dirt Poor, you would have to eat eight oranges to get the same amount of vitamin A that your grandparents got from a single orange in their childhood. So what can we do? We can start by not encouraging poor agricultural practices. Do a little homework. What sort of reputation does the company growing your lettuce actually have? If they treat their workers poorly, they probably treat the soil even worse. When shopping for produce, buy organic. Organic farmers meet stringent assessments that ensure they are not using or exposing our food to potentially harmful chemicals. Even if those chemicals can’t hurt us, they do harm the beneficial insects and microorganisms necessary for healthy soil. And don’t buy more than you need. According to the United States Department of Agriculture, Americans waste an average of one pound of food each day, or 30-40% of the total food supply. This waste costs a family of four $2,275 each year. Finally, grow what you can at home using integrated pest management and other least damaging methods. When planning your garden, keep the following tips in mind:
As I said earlier, we still do not fully understand the complexities of soil health. We can help improve soil health by reducing our interference and boosting biodiversity in our landscapes. Remember that soil needs time to rest. It needs to go through natural cycles. We need to give our garden patches permission to go fallow for a season. It might be good for us to take a breather now and then, too. If you grow blueberries, be on the lookout for these longhorned beetles.
No, we’re not talking about Texas longhorns. Blueberry stem borers (Oberea myops) are in a family of narrow beetles with long antennae (Cerambycidae). Also known as rhododendron borers and azalea borers, they are close cousins to raspberry cane borers. Adult blueberry stem borers are slightly over one-half of an inch long (15mm), light orangish brown, with long black antennae and two black dots just behind the head, on the pronotum. Larvae can be one inch long (25mm) and yellowish. Females lay individual eggs just under the bark and then mark the area by girdling the stem above and below the egg. This damage causes the stem tip to turn brown in early summer. After hatching, larvae burrow lower into the stem, creating an increasingly larger tunnel where they will live and feed for two or three years. Larval feeding weakens the plant, causing wilting, stem damage, and branch loss. If you look closely, you may be able to see tiny holes in the stem where larvae push out light-colored frass (poop) that looks like tiny segmented pieces of sawdust. Unlike currant borers, peach twig borers, and squash vine borers, blueberry stem borer larvae frass holes are oriented upward, so the use of a wire to stab the larvae tends to be ineffective because they stay safely below those holes. Adult blueberry stem borers tend to feed on the underside of leaves, especially on the midvein, causing calluses and leaf curling. While that feeding damage is minimal, you can use it as a tool to monitor your plants. Protected inside your blueberry plants, blueberry stem borer larvae are not affected by insecticides. While you can spray for adults, this is generally not worth the effort. The best control tool is your pruners. Pruning your blueberry bushes to keep them free of old, damaged, or rubbing stems is your best defense against blueberry stem borers. Tuber flea beetles are native to North America, but you will probably never see one. These dull reddish-black insects are only 7/100 of an inch long (2mm), but the damage they cause is much larger. And their range is expanding into South and Central America. Other plants vulnerable to tuber flea beetle feeding include eggplant, groundcherries, and tomatoes. Tuber flea beetles (Epitrix tuberis) are ranked as the Number One potato pest among their cousins:
Tuber flea beetles and their cousins are difficult to tell apart, so we will lump them together for the sake of discussion. Collectively, they are members of a group known as leaf beetles (Chrysomelidae). Like other flea beetles, tuber flea beetles damage fruit, leaves, roots, and tubers. Adults crawl, fly, and jump from plant to plant to eat the leaves and burrow into the soil to lay eggs. Larvae feed on roots and tubers before pupating into adults. Adult feeding causes tiny holes in leaves, creating a shothole appearance, bare patches on tubers, and leathery areas on fruit. A three-year crop rotation goes a long way toward managing tuber flea beetles, but buying certified disease- and pest-free seed potatoes is critical. Also, it helps to keep weeds in the nightshade family away from your potato plants. You can also reduce tuber flea beetle damage by intercropping dill, marigolds, and spring onions with vulnerable crops.
I hope your potatoes never get fleas! We’ve talked about black scurf and sweet potato scurf. Today, we’re learning about silver scurf. Silver scurf may sound like the latest Marvel comic hero, unfortunately, it’s a fungal disease of potatoes. For the most part, silver scurf is a cosmetic problem, but infection can lead to tubers rotting in storage, and they don’t look as pretty. Well, pretty for a potato. Potatoes infected with Helminthosporium solani can be shrunken, shriveled, and lighter in color. This disease causes spud dehydration and scabby bits. You may also see black spots, which are tiny fungal factories.
Other conditions that result in scabby potatoes include common scab, potato scab, and powdery scab. Scabby leaves often indicate Eriophyid mite feeding or bacterial spot, and scabby apples are a warning to look before you bite, because it may be a sign of codling moth larvae feeding. Apples are also subject to apple blotch and apple scab, while cucurbits can look less than their best due to belly rot and cucurbit scab. Until 1977, Thiabendazole (TBZ) fungicide was used against silver scurf. But as is often the case, the fungi developed a resistance. Other fungicides have been tried, but cultural controls provide a more sustainable method of reducing the chance of disease. Silver scurf occurs most often when temperatures are between 59°F and 90°F (15°C and 32°C), so pretty much all summer. Tubers left in the ground too long can also increase the likelihood of silver scurf. Crop rotation and early harvest are good ways to avoid this problem. Silver scurf is not to be confused with the lovely legume, silvery pea-scurf (Pediomelum argophyllum). Fusarium yellows is a disease of the cabbage family.
Closely related to Fusarium wilt, Fusarium yellows sometimes goes by that name. More commonly, it is simply called yellows. This disease is caused by Fusarium oxysporum f. sp. Conglutinans fungi. It occurs most often in crops grown during warm weather. The disease is at its worst when temperatures are between 80°F and 90°F (27°C and 32°C). The pathogen generally enters damaged rootlets at transplanting time, so be gentle with those babies. Symptoms of Fusarium yellows are easy to overlook at first. Infected plants become a paler version of their healthier selves. They develop a yellowish tint, rather than vibrant green. As the disease progresses, that discoloration becomes more obvious on one side of the plant. The leaves and stems on that side start to curve. Lower leaves, midribs, and petioles eventually wilt and die. Symptoms then move to the upper portion of the plant. If you look at a cross-section of an infected leaf or stem, you can see that the sap has turned dark brown, much like black rot, which turns sap black. The other difference is that symptoms appear in the upper portions of the plant first when black rot is the culprit. Infected plants should be removed and thrown in the trash. These fungi can live in the soil for many years. The best preventive methods include crop rotation, removing plant debris at the end of the growing season, and growing your brassicas during cooler weather. In 1905, Byrnes Young crossed “Mayes” dewberries with the “Phenomena” blackberry-raspberry hybrid, which resulted in Youngberries.
Youngberry plants Cousin to loganberries, nessberries, olallieberries, and tayberries, youngberry fruits (Rubus caesius ‘Youngberry') are slightly smaller and sweeter than blackberries. They can be dark red or deep purple to nearly black. They start ripening earlier in the season. Canes are moderately thorny, making them a nice choice as a security hedge. Thornless varieties are also available. Both varieties may have tiny prickles on new canes. As with other brambles, fruit is produced on second-year floricanes. These canes can be up to ten feet long and should be removed when fruit production ends. Plants are self-pollinating and can be grown in containers. How to grow Youngberries at home Youngberry canes should be installed in late winter to early spring. They thrive in slightly acidic, fertile clay or loamy soil and benefit from top dressings of aged manure or other compost. Like other cane fruits, they perform better when trellised or trained up a fence. Canes that touch the ground are likely to generate new plants. Be sure to provide good drainage and airflow. Like raspberries, your Youngberries may need shade in the afternoon to prevent sunburn damage. Allow for up to ten canes per plant. Plants should be spaced five to six feet apart. Youngberry plants are not drought tolerant, so regular irrigation is critical during the summer months. Youngberry pests and diseases Youngberry plants are known to be vigorous and highly disease resistant. But excess moisture and poor airflow can result in Fusarium wilt, gray mold, and Verticillium wilt. Fruit flies, spider mites, and thrips may also appear. Birds, grasshoppers, opossums, and other critters can be problematic. Netting may be necessary. You will probably never see these fruits in stores because they do not ship well, but I hope they make it to your garden. |
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