The Ribes plant family is a small but delicious group that includes currants and gooseberries. Botanically, Ribes is a genus (which is why it is italicized). The family name is Grossulariaceae, but Ribes is the only member of that family, so we will overlook that technicality. Ribes are native to the Northern Hemisphere. This pair of edibles is an interesting mash-up of characteristics. Gooseberries have thorny exteriors but tend to be well-behaved and undemanding. Currants, on the other hand, may look docile and approachable, but these plants defy description and can bring serious problems to a region. In fact, there are laws against growing Ribes in some regions! The Ribes family was banned in 1920. [I told you they were scoundrels!] This ban was put in place because Ribes can host white pine blister rust (Cronartium ribicola). This fungal disease has been devastating to East Coast white pines. Don’t worry, though. That ban was partially lifted in 1966, as resistant cultivars were developed. If you live in New Hampshire, North Carolina, or West Virginia, you are still not allowed to grow Ribes plants, as far as I know. If you live in Massachusetts, New Jersey, Rhode Island, or Delaware, you’ll need a permit. Currants Now, we’re not talking about those tiny raisins made from Corinth grapes when we say currants. Currants are small red, black, or white berries that grow in clusters. Scientists are still wrestling with this group, which defies classification. You can read more about that in my post on currants. Gooseberries Gooseberry plants have spiny stems and branches, making them tricky to work with. Since branches only produce fruit in a single season, removing heavily laden stems makes them easier to work with, plus it lets light in for new branches to grow. You can find sweet dessert varieties and tart culinary varieties. Gooseberries can be green, white, yellow, or reddish-purple. Ribes pests and diseases
Aphids, brown marmorated stinkbugs, clearwing moth larvae, currant borers, gooseberry fruitworms, gooseberry sawflies (Nematus ribesii), also known as currant sawflies, mites, imported currantworms, and the larva of some moths and butterflies are common Ribes pests. And birds. Problems are more commonly caused by mineral imbalances in the soil or improper irrigation. These plants are susceptible to several fungal diseases, such as American gooseberry mildew, anthracnose, currant cane blight, gray mold, leaf spot, powdery mildew, rust, and septoria leaf spot. Avoid overhead watering and be sure to provide good drainage. Ribes grow best in cool, moist surroundings with good drainage, but partial shade and regular irrigation make them possible elsewhere. These plants can be grown in containers and are self-pollinating. Ribes take well to regular pruning, making them excellent patio or balcony plants, and renewal pruning each winter keeps them healthy and productive. Ribes berries are delicious and their flowers provide nectar and pollen to a wide variety of butterflies.
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The mallow family (Malvaceae) is a mixed bunch. It contains several weeds and some favorite crops. It also includes several ornamentals, such as hibiscus, hollyhocks, and linden trees. Scientists are still arguing over the specifics of the mallow family, but let’s see how it applies to gardening. Mallow characteristics Most mallows are shrubs or trees that put out taproots. Leaves tend to alternate along a stem and are lobed. The leaves are usually smooth-edged. When they are toothed, you will see a vein reaching the edge of each tooth. You will also see a small, leaflike appendage at the base of each leaf, called a stipule. Stems of mallows contain mucous and may be covered with prickles. Mallow flowers tend to be large and showy. Fruits are usually capsules, nuts, or schizocarps. Members of the mallow family readily self-seed an area. Mallows grow best in full sun with regular irrigation in summer. Edible mallows Cocoa, kola nuts, and okra are members of the mallow family. So is durian, a tropical tree that produces giant-sized fruit. Some people love durian and others say it stinks. While you can’t eat it, cotton is also a member of this family. Even most of the mallow weeds are edible, but you probably don’t want to encourage them in your garden. Weedy mallows Mallow seeds have thick coats that protect them from harm. Those coats also slow germination until conditions are ideal. Very often, those seeds are weed seeds, and they can spread like crazy. Most mallow weeds are invasive to the US and are easily mistaken for one another. Common mallow weeds include:
Many of these weeds are edible, but they can also carry disease. Mallow pests and diseases
Weedy members of the mallow family can carry several diseases, including rusts, tomato yellow leaf curl, and tomato spotted wilt. Members of the mallow family are also susceptible to bacterial leaf spot, gray mold, and phytophthora blight. Aphids and spider mites are the most common pests. If you grow hollyhocks and okra, you may want to keep them at a distance from each other, to prevent the spread of disease. Finally, the marshmallow plant (Althaea officinalis), a native herb of Europe, is a member of this family and its roots were used to make marshmallows some 4,000 years ago in Ancient Egypt. Today, marshmallows are made out of sugar and gelatin. There’s more to the grass family than just your lawn. Grains and grasses (Poaceae) have long been a part of home gardens, landscapes, and agricultural fields. This group is the fifth-largest plant family and it includes cereal grains, bamboo, lemongrass, sugarcane, and coffee. [That last one surprised me, too.] Let’s see how these plants are all related and how many of them may be good additions to your garden. To start, members of this group are usually divided into grasses and cereal grains. Grass plants Grasses are monocots with fibrous roots and hollow stems, except at the nodes. They have narrow leaves that appear alternately up the stem. Each of those leaves wraps around the stem, creating a leaf-sheath, rather than growing out of a petiole. Very often, you will see a fringe, called the ligule, where the sheath meets the stem. This growth is believed to keep water and pests from entering. It can also be used to help with plant identification. Grass plants reproduce most commonly by seed, though some use rhizomes to create daughter plants, known as tillers. Grain seeds are encased in simple dried fruits called caryopses. Flowers of the grass family tend to form spikelets. These plants can be annuals or perennials, depending on the species. Unlike most other plants, the meristem tissue [think undifferentiated stem cell] of grass family plants is found near the base of the plant, rather than higher up. This allows the plants to recover from grazing (and mowing). These plants are all heavy feeders that use a lot of nitrogen. Planting them in blocks, rather than rows, increases pollination. Cereal grains Cereal grains are classified as warm-season or cool-season cereals. Corn, millet, and sorghum are warm-season cereals that need lots of sunlight and heat to thrive and are better able to withstand drought. Cool-season cereals include barley, oats, rice, rye, spelt, wheat, and wild rice. Many people consider amaranth, buckwheat, and quinoa to be cereal grains, but they are not. Instead, these are all broadleaf (dicot/eudicot) plants known as pseudocereals. Other seeds that are not grains include lentils, peas, and other legumes. And that “recreational/medicinal” grass? It’s not a member of this family either.
Grass family pests and diseases Grains and grasses are prone to fungal diseases, such as leaf scald, leaf spot, net blotch, stripe rust, and stem rust. Along with grasshoppers and crickets, and other common pests, this family battles crane flies, stinkbugs, and wireworms. Also, aphids may carry a viral disease called barley yellow dwarf. Your average lawn grass has a root system that only goes down a few inches. Other grass plants have roots that can go down 5-10’ or more. So, how about making a little room for a patch of grain? As a food crop, I expect that it will be much like endive, nasturtiums, lentils, and tomatoes—it will continue to turn up long after I have stopped planting it. The grain and grass family provides 51% of all human dietary energy. How much space does it get in your garden?
There are four predatory stink bugs found in the U.S., mostly in southern states. Anchor stink bugs Anchor stink bugs (Stiretrus anchorago) are from Central and North America. They occur in several different color variations, ranging from black, white, and tan, to orange or red and black, to green and yellow. Florida predatory stink bugs Found predominantly in the southeastern U.S., Florida predatory stink bugs (Euthyrhynchus floridanus) hunt grasshoppers and other garden pests. They go after these larger insects by hunting in packs of up to twelve individuals. These bugs are just under ¾” long and bluish-black or purplish-brown with red rear ends with black markings, though they also come in a variety of colors. They have sturdier snouts than their sap-sucking cousins. Giant strong-nosed stink bugs The giant strong-nosed stink bug (Alcaeorrhynchus grandis) is found in South and Central America as well as in southern U.S. states. These bugs can be nearly 1” long and they have two distinct points on their backs. They tend to be variegated brown with dark bands on their legs and dark spots on their bellies. Some individuals are red with black leg bands. Unlike the smaller egg clusters of other stink bugs, the giants lay eggs in masses of 100-200 eggs. Nymphs have a bluish-black thorax and red abdomens with dark stripes. Spined soldier bugs Spined soldier bugs (Podisus maculiventris) are found throughout North America. They prefer feeding on the larvae of cabbage loopers, Colorado potato beetles, diamondback moth caterpillars, European corn borers, flea beetles, gypsy moths, imported cabbageworm larvae, Mexican bean beetles, and velveteen caterpillars, so count yourself lucky if you have these hunters in your landscape. You can even buy spined soldier bugs eggs to add to your IPM program. As you search your garden for stink bugs, with a bucket of soapy water in hand, keep in mind that not all of them are bad. Sorting between beneficial and pest stink bugs is made a little easier because many predators tend to be more brightly colored and patterned.
Which types of stink bugs have you seen? Red-shouldered stink bugs may invade your home as well as your garden. Red-shouldered stink bugs (Thyanta custator) use their piercing mouthparts to suck the juices from your almonds, apples, beans, corn, peaches, pears, pistachios, tomatoes, and wheat. Their feeding can cause cat-facing and corky fruit, as well as provide points of entry for other pests and diseases. And, of course, they poop on those crops, too. Red-shouldered stink bug identification Adult red-shouldered stink bugs are primarily green but can be brown, with a pinkish edge along the scutellum (just behind the head). That pink edge can be very dark and noticeable, barely present, or missing entirely. They have long antennae (for a stink bug) and, if you flip them over, you will see some of them have black spots on the abdomen. Nymphs are brownish, with tribal-like designs on their backs. Adults and nymphs average 1/3” in length. Eggs are grey, round to barrel-shaped, and flat on top. Red-shouldered stink bug lifecycle Tiny eggs are generally laid in clusters on plant stems and the underside of leaves. When those eggs hatch, nymphs start feeding on developing seeds and young leaves, buds, and flowers. As they mature, their diet expands to include all those crops mentioned earlier. Then, as temperatures begin to drop, they start looking for a place to overwinter. That winter wonderland may be in mulch, plant debris, or your living room. Similar to ladybugs, red-shouldered stink bugs are notorious for invading homes in autumn. And don’t try vacuuming them up or your vacuum will stink. Instead, invert a plastic bag over your hand, pick those little suckers up, and drop them into a container of soapy water. The same method works outside in the garden, as well.
Stink bugs can smell pretty bad. Even my hens turn up their beaks when one crawls by, so it’s up to you! When I say ‘stink bug’, you probably think of a green or brown shield-shaped bug, and you’d be right. But Say stink bugs (Chlorochroa sayi) can be such a dark green that they look nearly black with orange edging in winter. Then they switch to bluish-green with white edging in summer. This pest is native to western North America, but its range is expanding. Say stink bug identification and lifecycle These are large bugs, averaging ¾” in length. While in their green phase, adult Say stink bugs also have three light spots near where their shoulders would be, if they had shoulders. You may also see a white or pink spot just above where the wings emerge on nearly mature nymphs. Females lay clusters of 30 or so white, barrel-shaped eggs on plant material. Those eggs hatch into nymphs. At first, those nymphs stay clustered together for a few days before dispersing in search of tender flowers and germinating seeds. They also eat young leaves. Nymphs are smaller and softer than adults and do not have wings. They go through several developmental stages, or instars, before reaching adulthood. There can be up to three generations each year, depending on the length of the growing season. Say stink bug damage Despite their fascinating wardrobe changes, Say stink bugs are much like other stink bugs. They emerge from leaf litter and ground cover in early spring, feeding on mallow, mustards, Russian thistle, and other favored weeds until your garden starts happening. They then move in, feeding on all those seeds you just planted. They especially like members of the grass family, which means alfalfa, barley, corn, millet, oats, rye, and wheat are all at risk, as well as your lawn. Then they go after your beets and tomatoes. Especially tomatoes. Using piercing mouthparts to suck the juices from your plants, Say stink bugs may also introduce yeasts that cause fruits to rot. Say stink bug management
Removing weeds is one way to make your garden less inviting to Say stink bugs. Avoiding the use of broad-spectrum pesticides will encourage beneficial parasitic wasps and tachinid flies. And, as much as I dislike pill bugs, they do eat stink bugs eggs. At the end of autumn, remove over-wintering sites by composting leaf litter and other dead plant material, rather than leaving them in place. Have you seen Say stink bugs in your garden? Let us know in the comments! Green stink bugs are probably the easiest to spot in mulch and wood piles and one of the hardest to see among your plants. Common green stink bugs (Acrosternum hilare and Chinavia hilaris), also known as green soldier bugs, are bright green with red, orange, or yellow edges. One oddball is bright orange! Adults are ½ to ¾ inches long. Nymphs have bright dark bodies with orange edges near the front and yellow on the back. Barrel-shaped eggs are laid on the underside of leaves in double rows of twelve or more eggs. Eggs are also commonly found on the stems of salvia. A smelly subject Stink bugs get their name because they can smell bad. Both adults and larvae have large stink glands. When they are disturbed, they spew those smelly chemicals to deter potential predators. [Generally speaking, even my hens avoid them, which is a shame when you consider all the damage they can do.] Green stink bug damage Green stink bugs are found throughout North America. Using their piercing mouthparts, they damage a wide variety of garden and tree crops. The juicy fruits of apple, cherry, orange, and peach trees are common targets, leaving behind a trail of corky fruits prone to fungal diseases and other problems. As green stink bugs mature, they shift their focus to the seeds, stems, and leaves of beans, corn, eggplant, peas, soybeans, and tomatoes. Green stink bug lookalikes Green stink bugs are differentiated from southern stink bugs (Nezara viridula) by their black outermost antennal segments. There is one other green stink bug, Chinavia pensylvanica (no common name), found rarely in Maryland. That species has a more arched back (if you’re into that sort of thing). Green stink bug control Tachinid flies and parasitic wasps will lay their eggs in green stink bug eggs to provide a handy meal for their young, but there are often not enough of them to control a bad stink bug problem. Pheromone traps can be used, as well, but those traps attract pests which I find counterproductive. Those traps are used more effectively as monitoring tools. As with other stink bugs, the best control methods are being alert and handpicking. If you drop stinkbugs into a container of soapy water, the smell isn’t a problem.
We've already discussed invasive brown marmorated stink bugs and native Uhler's and rough stink bugs, but there are more than 4700 species of these shield-shaped pests worldwide and over 200 species in North America. Consperse stink bugs (Euschistus conspersus) are one of those. Stink bug damage
Nearly all stink bugs are sap-sucking pests. I say ‘nearly’ because stink bugs are omnivores and there are even some predatory stink bugs. We’ll get to them another day. Stink bugs suck the life out of buds, fruits, leaves, and stems. Damage caused early in the growing season can lead to cat-facing later on. If you find corky areas underneath the skin of fruits, it was probably stink bug feeding. Being omnivores, stink bugs also eat pesky beetle and caterpillar larvae, so they aren’t all bad. I still don’t want them in my garden. Consperse stink bugs, in particular, love apples and pears over everything else. They are also fond of almonds, blackberries, mustards, and many vegetables, including beans and tomatoes. Damage is worst during dry summers. Consperse stink bug identification Adult consperse stink bugs are ½” long and have greenish-grey to pale brown shield-shaped bodies, yellow underbellies, yellow to orange legs, and red antennae with darkened tips. You may also see alternating dark and light bands around the edge, or margin, of the upper shield. Nymphs can range from white to black with reddish markings. As they mature, they turn brown with black markings. White, barrel-shaped eggs are laid in clusters on leaves and twigs, and turn pink before hatching. Consperse stink bug lifecycle Like other native stink bugs, consperse overwinter in groundcover, emerging as soon as there are tender young weeds and other host plants to eat. Eggs can hatch in less than a week and nymphs can reach adulthood in a little over two months. Female consperse stink bugs lay an average of 225 eggs, but one researcher saw those numbers go as high as 640! This is why it’s so important to eliminate them as soon as you see them. Consperse stink bug management Consperse stink bugs eggs are often eaten by ants, earwigs, damsel bugs, and adult stink bugs. Except for predatory damsel bugs, most of us don’t want the rest of those critters in our gardens any more than necessary. There are commercially available pheromone lures that work to limit stink bug populations. Combined with sticky cards, these lures can be very effective. Keep in mind, however, that pheromone lures attract pests. Your best control measure is to be on the lookout and stomp any you see. Yes, they do stink when threatened or squashed, but it’s a small price to pay to protect your crops. Are damaged areas on tomatoes due to dehydration, deficiency, or disease? Is it blossom end rot, sunscald, or buckeye rot? And what can you do about it? Let’s look at all three in more detail so you will know what to do if you see damaged areas on your tomatoes or peppers.
If there isn’t enough water available to move the calcium to where it is needed, cell walls surrounding the blossom end of the fruit will collapse, creating a uniformly dark brown or black area ONLY on the lower sidewall or blossom end of the fruit. If you see blossom end rot, irrigate more heavily and more often. If the damaged area is lighter in color and higher up the side of your fruit, it may be sunscald.
Buckeye rot symptoms
Buckeye rot is a disease caused by three different types of Phytophthora: P. capsici, P. drechsleri, and P. nicotiana var. parasitica. Phytophthoras are water molds (oomycetes) responsible for several plant diseases. This disease is common in the southeast and south-central regions of the United States but has been found elsewhere. It occurs most often after extended periods of warm, wet weather with temperatures ranging from 75°F to 86°F. Buckeye rot can infect tomatoes, peppers, and eggplant, as well as pineapples, potatoes, and tobacco. At first, all you may see are smooth, grayish-green water-soaked spots. Damping-off and stem cankers may also appear. As the disease progresses, those lesions turn into the classic bull’s eye pattern of large, concentric rings, alternating between light and dark brown. The edges of these lesions will be smooth but not clearly marked. Eventually, white fungal growth can be seen on the lesions. Other diseases that may exhibit similar symptoms include anthracnose, cucumber mosaic virus (CMV), and late blight. In each case, some differences can help you diagnose the problem:
Buckeye rot management Starting with healthy, disease-free seeds and plants is the first step toward preventing nearly all plant diseases. Since buckeye rot spores can travel on seeds, transplants, clothing, and garden tools, it’s a good idea to keep things clean. Spores can also be splashed onto healthy plants by rain and overhead watering, so use soaker hoses or water at ground level and allow the soil surface to dry out between waterings. Mulching around plants can reduce the splash effect, as well as reduce weeds and evaporation. You can reduce the chance of many fungal diseases by providing good drainage and reducing soil compaction. Since buckeye rot spores are found in soil, the disease is most likely to affect fruits closer to the ground. If you keep fruit up high with stock panels, tomato cages, or trellising, you can reduce the likelihood of buckeye rot occurring. Three-year crop rotations are also believed to help prevent buckeye rot. Now you know. Touted as a miracle soil amendment, what’s true about rock dust and what’s not? Also known as mineral powder, rock flour, rock powder, rockdust, or stone powder, and soil remineralizer, rock dust is what’s leftover from mining and quarry work. This finely pulverized material claims to contain important plant nutrients, “enhance the ability of beneficial microbes to flourish”, improve plant structure, increases water retention and resistance to pests and disease, and create “intense flavor profiles for fruits and vegetables”. Wow. That sounds pretty important and impressive, doesn’t it? While it’s certainly true that plants need nutrients to grow and thrive, let’s see what research says about those claims. We can start by learning what, exactly, is in that bag of rock dust. What is rock dust?
The contents of your rock rust shipment will depend entirely on where it was mined. It may contain a lot of calcium. Or none. The same is true for other minerals. That being said, on average, rock dust contains significant amounts of aluminum, silicon, and sometimes iron. It may also contain copper, magnesium, manganese, potassium, sulfur, and zinc. But does your soil need these elements? Without a lab-based soil test, you really can’t be sure. Your rock dust may also contain toxic levels of aluminum, arsenic, cadmium, chromium, copper, lead, nickel, and sodium. Believe me when I tell you that dealing with toxic levels of nutrients is a lot harder and takes a lot longer than adding missing nutrients. I’m speaking from experience. If you do nothing else for your garden this spring, get your soil tested before you add anything. Big batch or specific sediments? If your soil is low on a certain nutrient, rather than relying on luck, you can order specific types of rock dust. If you know your soil is low in something, you can apply crushed versions of that nutrient in the form of rock dust. Of course, it costs more that way. The nice thing is, it is an organic method of fertilizing your plants. Making rock dust work for you If you decide to apply rock dust, combining it with nutrient-rich organic matter, such as aged compost or manure, creates a slightly acidic environment more likely to break down the dust into bits small enough to be carried by irrigation water into your plants. What rock dust is not Because it does not contain significant levels of nitrogen, phosphorus, or potassium, rock dust is not a fertilizer. Bottom line, in my opinion, rock dust is best left to commercial growers who regularly deplete their soils through heavy use and often have a fleet of chemists, soil experts, and lab technicians on hand to determine what’s needed and what’s in each particular load of rock dust. Butt rot? Really? Yes, Virginia, there is a fungal disease of almond trees called butt rot. Is full name is Ganoderma root and butt rot and it can kill your tree. When most people use the word “butt” they are talking about a certain mammalian body part. When botanists and gardeners say “butt” they mean the base of a tree. In either case, butt rot is not something you want. Butt rot is very common in Europe and California. This disease is responsible for many orchards having to be removed completely. Butt rot kills young trees outright and infected mature trees must be removed to prevent the disease from spreading. Butt rot is caused by three different bracket or shelf fungi from the Ganoderma genus: G. adspersum, G. brownii, and G. polychromum. Another type of Ganoderma root and butt rot, caused by G. applanatum, attacks oak trees. All of these fungi devour wood. Butt rot symptoms At first, infected trees simply fail to thrive. Then they decline. You may see shelf-like conks grow along the trunk or clefting at the graft union. Clefting describes the way the two halves of a graft union peel apart. You may see branch dieback within the canopy and leaves may be smaller than those of healthy trees. The rooting of infected trees tends to be more shallow than normal. Eventually, the tree will break off at ground level, so keep your distance. This disease infects the canopy and trunk, causing both heartwood and sapwood to rot. This makes trees structurally unstable and unsafe to be around. Eventually, branches start breaking off and the tree dies. Before that happens, there are steps you can take to prevent butt rot. Butt rot management
Butt rot is spread by airborne spores that enter through wounds in the bark, so the most important way to prevent butt rot is to protect your tree’s bark. Keep edgers and mowers at a distance. Remove rubbing branches and unnecessary tree supports. As soon as there is a wound, fungal spores can enter. Before you paint over that wound, you need to know that that can cause even more problems by holding moisture against the trunk. Better to not injure the tree in the first place. If a wound occurs, let the tree heal itself. A callus will form. Hopefully, before pests or disease use it as an entrance. Good drainage is also important. You can improve drainage with mulch and by top dressing around trees with aged compost, just make sure nothing is touching the trunk. It’s a good rule of thumb to leave at least 8-12” of bare ground between tree trunks and mulch. Other preventative measures include: • leave clean cuts when pruning • prune and train trees for good airflow and structural strength • avoid digging or rototilling around trees • whitewash exposed branches and trunks • remove tree supports as soon as they are no longer needed • ensure that sprinkler spray does not hit tree trunks If you have a tree with conks, you should contact a certified arborist. They can inspect the tree for structural integrity and determine the cause and extent of any infection. Fusicoccin, or constriction canker, is a fungal disease of almonds and peaches.
You may find this word easier to say than to read at first. It is pronounced FUSE-ih-koksin. Once you say it aloud a few times, it doesn’t feel nearly as intimidating. [Unfortunately, I couldn’t find a few image, but I have a request in the works.] When I first found this word, the disease was not present in California. Now it is. These things keep moving forward which is why we need to keep learning. Fusicoccin is a disease that forces plants to open their stoma. Stomata are tiny breathing holes found most often on the underside of leaves, but also on stems and other tissues. Plants use stomata to create bubbles of high humidity which then evaporate, pulling moisture up a plant’s vascular system. This is how plants pull water from the ground and it’s pretty amazing when it works the way it should. When stomata stay open, plants start drying out. Disease progression This disease is caused by the Fusicoccum amygdali fungi, which is found throughout the United States, Argentina, China, Spain, Italy, and Hungary. These fungi produce chemicals that acidify plant cell walls, causing stoma to open permanently. They enter plants through leaf scars and stipules in the fall and bud scars, blossoms, and fruit scars in spring. Basically, any place there is a fresh opening. Fusicoccin symptoms The first sign of fusicoccin is wilted leaves and shoots, followed by long, brown cankers on infected buds and nodes. These symptoms are usually seen in early summer and become worse as the disease progresses. You may see constructed areas at the base of infected shoots. Gum may be seen oozing from infected areas, but don’t use that as a diagnostic tool since gumming is a common response to several diseases and disorders. Fruit on infected stems tends to shrivel up and fall to the ground, further spreading the disease. Managing fusicoccin Research has shown that certain fungicides can control this disease. But many of these products can cause birth defects, cancer, and infertility. Not exactly what you want around your tomatoes and basil! Another option is to fight fire with fire. Or, in this case, fight fungi with fungi. Trichoderma harzianum and Trichoderma viride are antagonistic fungi that work as biofungicides, parasitizing fusicoccin pathogens. Of course, they will also damage your homegrown mushrooms. As gardeners, we must choose our battles. You can buy these biofungicides online or from your local garden center. In the case of fusicoccin, prevention involves keeping trees healthy in the first place, applying biofungicides according to package directions, and buying resistant varieties whenever possible. If fusicoccin appears on your peach or almond trees, remove infected branches by cutting several inches below the affected area and throwing those twigs in the garbage. Hull rot isn’t a warning to sailors, but your almond tree may be at risk. If you grow almonds, your tree goes through several stages before producing a crop. Being deciduous, winters are spent bare and quiet. In late winter or early spring, a riot of flower blossoms appears, followed by leafing out. Where each of those flowers had been, fuzzy green almonds begin to develop. It’s amazing how many almonds a small tree can produce each year! As those almonds ripen, they get fat. Ultimately, the hulls dry and split open. When that occurs, hull rot may invade the nuts, threatening the life of your tree. Hull rot can be caused by one of three different fungi: Monilinia, Rhizopus, or Aspergillus niger. Aspergillus niger also causes sooty mold. If you notice leaves on shoots withering and dying, take a closer look. {Sadly, I was unable to find any photos I could use, so you’ll have to Google “almond hull rot” to see what it looks like.
Hull rot symptoms You may see brown areas on the outside or inside of the hull (Monilinia). You may see black fungal growth on the inside of the hull, between the hull and the shell, or on either side of the edge that opens (Rhizopus stolonifer). Or, you may see black spores between the hull and the shell (Aspergillus niger). Each of these is a type of hull rot. These fungi produce toxins that kill fruiting spurs and the twigs to which they are attached. Almonds on infected branches are harder to remove than healthy ripe nuts. Ultimately, shoots, strikes (fruiting wood), and lower limbs dieback. Hull rot prevention and management Healthy trees are less likely to become infected in the first place, so irrigate and fertilize trees properly. This means feeding your trees with aged compost or fertilizer at regular intervals in spring and summer, and providing 2-3” of water each week in summer. While an almond tree can survive and produce fruit with as little as 8” inches of water in a year, crop sizes and tree health are greatly improved when trees get a total of 54-58” of water each year. As your almonds start to split, cut back on watering by 10-20%. This is called deficit irrigation and it should be maintained for 2 weeks before returning to regular watering. Deficit irrigation improves nut flavor and reduces the chance of hull rot. Cut back on nitrogen fertilizers, too, for 40 to 60 days before harvest. Speaking of harvest, get those almonds off the tree as soon as they are ripe and toss them in the freezer for a couple of weeks to kill any worms that may be present. Always remove and dispose of mummies, which can harbor hull rot and several other diseases. And avoid damaging your tree’s trunk. Bark provides good protection against pests and diseases. And if fungal diseases are common in your landscape, avoid overhead watering, which can bounce fungal spores up into healthy plants If your tree is badly infected, you may need to resort to chemical fungicides. The products effective against hull rot are generally not available to the public, so you will need to contact a certified arborist for help. Hopefully, your almond tree will never become infected with hull rot. Golden pearls look like tiny tomatoes or yellow currants, but they taste more like cherries and can make you very sick if you eat them before they ripen. Native to Africa and Europe, golden pearls (Solanum villosum) are now found in Australia and North America. Also known as golden wonderberry, hairy nightshade, red nightshade, and woolly nightshade, this sprawling annual is considered a weed by many. These members of the nightshade family produce clusters of yellow or orange berries that are sweet and edible when ripe and can make you very sick if eaten when unripe. The hairy leaves are also edible, but similar to poke sallet, the leaves must be boiled a couple of times to be safe to eat.
Golden pearls plants Golden pearls make nice container plants and they begin producing fruit early in the growing season and will continue into autumn. Golden pearls that are grown in containers will produce smaller fruit than plants growing in the ground or raised beds. These plants tend to be bushy and can grow 36” tall. How to grow golden pearls Seeds are best started indoors or in a protected spot once temperatures begin to rise and your last frost date is behind you. Only cover seeds lightly, if at all, with soil. Keep them moist using a mister or water from the bottom with a tray until they sprout. This will keep them from being flooded into a corner. Seeds are slow to germinate, taking 20 to 40 days, but they grow quickly once they get going. Plants should be spaced 24” apart and watered regularly. They prefer moist soils and can tolerate partial shade though they grow best in full sun. Golden pearls are not as sweet as groundcherries, but they just might make a nice addition to your garden, landscape, or patio. What can leap small buildings and decimate your garden before you’ve had your first cup of coffee? Deer. Yes, Bambi’s family can destroy a garden in short order, and keeping them out can be challenging. Waking up to find your prized hostas, delicious strawberries, and crisp lettuce plants eaten down to nubs can be very frustrating. The more you know about deer, the better you can protect your herbs, trees, and produce from these athletic grazers. Yes, they are beautiful. And who hasn't wanted to pet a spotted fawn? Before you start defending a deer’s right to eat and live, you need to know that deer often carry Lyme disease, as well as ticks and fleas. Other diseases deer may carry include chlamydiosis, leptospirosis, Q fever, salmonellosis, and tuberculosis, just to name a few. The real problem with deer is their appetites. They can ruin a hedgerow, eliminate entire garden beds, and kill trees in their search for food. To keep deer out of your garden or landscape, you have a few options. Culling Some municipalities offer culling services. In this case, hunters come to your property and shoot some of the deer. This reduces the number of deer feeding on your tomato plants and makes the remaining deer a little more cautious, for a while, at least. Many times, the venison is then given to local charities to help feed those in need. Many people see this as cruel but consider my story. Culling and hunting were banned many years ago while I lived in Virginia. At that time, I was volunteering with Fish & Wildlife, doing hawk-banding and eagle counts, so I was spending a lot of time out in the woods, hiding in a blind. What I saw was heartbreaking. The deer were starving to death. There were simply too many of them. They were mangy and diseased and suffering. People had already killed off many of the predators that would have restored the natural balance and deer, being prey animals, are very prolific. They had bred themselves into starvation. It made the bullet from a hunter’s gun look humane by comparison. When my mother lived on 97 acres in Upstate New York, my then brother-in-law would hunt a few deer and we would get a Christmas box of frozen, wrapped venison. It was delicious, but my mother never won the war against deer in her rural garden. Her plot was too far from the house and she wasn’t willing to install adequate fencing. Deer fencing A healthy adult deer can leap over anything lower than 10’ tall. Most people don’t want a 10’ fence around their garden. Some people have found that a solid 6’ fence topped with an additional three- to four-foot mesh works, presumably, because the deer can’t see what they’d be jumping into. Electric fences can be somewhat shorter, though they do require regular monitoring. I can tell you from personal experience, touching a hot wire isn’t something you’ll forget any time soon. The advantages of electric fencing are they are less obtrusive, cost less than solid fencing, and they don’t actually harm the deer. [I recently heard about electronic posts that smell like acorns and deliver a shock when touched. Does human ingenuity ever end? I hope not!] Another tricky fencing solution is to use two 4- to 5-foot fences placed four feet apart. This is believed to confuse the deer since it is difficult for them to clear both fences and they don’t like to feel boxed in. If garden-wide fencing isn’t an option for you, tall cylinders of wire fencing can be used around individual beds or plants to protect them from deer feeding. You may also want to try stringing a fishing line strategically around your garden and landscape where deer frequently walk. They will run into the invisible barrier and feel threatened. Just watch out you don’t clothesline yourself! Plant choice
If you grow apples or cherries, beans or beets, blueberries, broccoli, cabbage, cauliflower, pumpkins, spinach, well, if you have a garden and there are deer in the neighborhood, there’s going to be a problem. Deer will always go for arborvitae, azaleas, hardy geraniums, hosta, rhododendrons, roses, and tulips. There are some plants, however, that deer don’t eat. By installing plants that deer are unlikely to eat throughout the landscape, deer should be less likely to cause significant damage. These plants include most herbs, mint and lemon balm, members of the onion family, artichokes, asparagus, eggplant, fennel, figs, lavender, and rhubarb. They also seem to avoid plants with fuzzy leaves, such as lambs ear or yarrow, prickly plants, and plants toxic to deer. That list includes bleeding hearts, daffodils, false indigo, hellebores, monkshood, poppies, and spurges. There are also plants that deer would rather not eat, but will if they are particularly hungry. This group includes tomatoes, peppers, and potatoes, squash, cucumber, Brussels sprouts, cilantro, horseradish, okra, melons, and chard. Keep in mind that tender, young shoots of nearly every plant are considered fair game by deer, and deer do not read reports or studies, or blog posts about what they do and do not eat. If your local deer love artichokes and horseradish, you’ll have to figure out ways to protect them. [Rutgers University offers an extensive list of what deer do and do not generally eat.] Scare tactics Deer spook easily, so sudden noises and movements can make them turn and run. You can use plastic bags tied to the tops of poles, old CDs hanging in trees, pinwheels, or windchimes. Like scarecrows, scare tactics lose their effectiveness over time. Commercial growers use air cannons but your neighbors probably wouldn’t appreciate that one. Garden hoses attached to motion-detectors are said to be effective. I can’t help but picture a herd of deer lounging on my lawn, nibbling garden treats and enjoying the cool spray, like a bunch of kids playing in the sprinklers on summer vacation. I could be wrong. I had a neighbor, many years ago, who entertained the neighborhood children each Halloween with well-thought-out theatrics, which often included a leaf-blower attached to a motion detector. It just might work to protect your garden plants, too. The big stink Deer rely heavily on their sense of smell and they avoid areas frequented by predators. If they smell predators, they will generally go down a different path. You can find countless recipes online for DIY deer repellants. I have no idea how well any of them work, and some of them sound awful. Personally, I have used Bobbex-R with good results. It stinks (to humans) for about 45 minutes, then goes away. Deer, rats, and squirrels tend to avoid it for several weeks. I imagine that other commercially available deer repellants work in much the same way. Pungent herbs and scented geraniums are known to repel deer, as does cheap perfume sprayed on strips of fabric and zoo poo from the lion’s den. If you have dogs, they can help discourage deer from grazing in your garden. Other tips to reduce deer damage include:
And be sure to switch things up. Deer can get used to just about anything, especially if they are hungry. If you move things around and cycle through different deer repelling tactics, they are more likely to be effective. Tell us your deer story! How do you keep deer out of your garden? We’ve all seen them – spiders with tiny, little bodies and long, delicate legs. What you may not know is that daddy longlegs aren’t actually spiders. And what many of us call daddy longlegs are actually cellar spiders. Or crane flies. Before we get into the differences and similarities, we need to put aside a common misconception. Urban myth states that daddy longlegs have the most potent venom of any spider and that the only reason they aren’t a danger to us is because their fangs are too small to bite us. False on both counts. Daddy longlegs can bite you and their bites won’t hurt you. Their venom is relatively weak. To figure out which insect you have, you should first ask yourself if it has wings. Crane flies If you see a daddy longlegs with wings, it’s a crane fly. Crane flies are the recipient of a different urban myth. As children, we called them mosquito-eaters because we thought they ate mosquitoes. We were wrong. Crane fly larvae feed on the crowns, leaves, and roots of your lawn and other members of the grass family (Poaceae or Gramineae). This includes barley, corn, lemongrass, millet, oats, rye, sorghum, and wheat. Crane flies are pests. If there are no wings present, it’s a spider. Cellar spiders The long-legged spiders most of us see are cellar spiders. These spiders have oval- or peanut-shaped bodies and extremely long, delicate legs. If you are willing to get close enough to see [and I urge you to, these creatures are amazing up close!] they may have 6 or 8 eyes, arranged in groups of 3 or 4, respectively. Cellar spiders may be gray, tan, or brown and they often have chevron markings. These spiders hang upside down from their webs and will shake them when they feel threatened. Cellar spiders build messy, irregularly-shaped webs, which are often found in caves, under loose bark, and in the upper corners of many living rooms, garages, and attics. These webs are not sticky, just confusing. Prey become entangled, are bitten, and then thoroughly wrapped up to be eaten later. After being consumed, prey are removed from the web and their empty husks are dropped to the ground. Rather than feeding exclusively on flies and gnats, cellar spiders prefer eating other spiders. They will often shake the webs of neighboring spiders to trick them into thinking a tasty snack has been trapped. Instead, a fatal bite turns the host spider into the next meal. Funnel weaver spiders, hobo spiders, huntsmen, house spiders, and redback spiders are all favorites of the cellar spider. [Redbacks are related to black widow spiders.] This makes cellar spiders helpful in the house and the garden, reducing the number of potentially dangerous spiders. In a classic win-win situation, cellar spiders are “synanthropic”, meaning they benefit from living near us, too. Members of the Pholcidae family, these arachnids go by several different names: carpenter spider, long daddy, marbled cellar spider, skull spider, vibrating spider, granddaddy longlegs, and daddy longlegs, hence the confusion. Daddy longlegs Daddy longlegs have fatter bodies than cellar spiders, and they have a brown stripe on their belly. There are 6,000 to 10,000 species of daddy longlegs worldwide and they’ve been around for 400-million years, with very few changes. This group belongs to the Opiliones order. While Opiliones are arachnids, they are not spiders. The Arachnida class includes harvestmen, mites, scorpions, Solifugae (camel spiders), spiders, ticks, and may include horseshoe crabs. Scientists are still sorting that out. True daddy longlegs are harvestmen, not spiders. They are most closely related to mites. If you were to compare cellar spiders with daddy longlegs, you would see that daddy longlegs have single eyes (or no eyes, depending on the species) and fused, pill-shaped bodies. They also differ in that they do not build webs, do not produce venom, and can eat chunks of food, as well as liquids. They defend themselves using stinky chemicals.
These creatures prefer hiding in moist areas, under logs and rocks, so you may find one under your kitchen sink or in a crawl space or basement. Daddy longlegs are fascinating. They breathe using tracheae in their legs. And if one of those legs breaks off, as they too often do, it will continue to move because of a pacemaker mechanism found in each femur. This movement may continue for up to an hour. Scientists think this may have evolved to trick predators. While daddy longlegs are predators in their own right, they get most of their nutrients from decomposing plant and animal matter, and manure. When they do hunt, they ambush their prey. This is impressive because their eyes cannot form images. [Don’t ask me. I have no idea how they do it.] Daddy longlegs daddies are territorial and often care for the eggs laid by several different females, cleaning the eggs and protecting them from unrelated, egg-eating female daddy longlegs. [And we think our families are complicated!] So, crane flies are pests, cellar spiders are helpful, and true daddy longlegs are pretty much neutral. Now you know. Plant stems are divided into nodes and internodes. Nodes are small knobby areas found on stems. You need to know about nodes when pruning and tree training. Internodes are the spaces between nodes and the length of internodes can tell you secrets about your plants Nodes and leaves Nodes produce buds, tendrils, and leaves. Sometimes those leaves have stems, called petioles. When identifying a plant, it helps to note if the leaves are arranged opposite each other, alternate up the stem, or are in a whorled pattern. Even if there are no leaves present, you can use the nodes and leaf scars to find the same information. Leaf scars are where petioles used to be attached. They look like tiny crescents. Whorled arrangements are a little trickier to identify without leaves because nodes can produce multiple leaves. Modified stems Aside from the normal stems we see coming out of the ground, there are also stems that run along the soil surface and underground stems. Aboveground modified stems can be crowns, spurs, or stolons. Stolons are often called runners, which is only partly true. All runners are stolons, but not all stolons are runners. Strawberries use runners to send out daughter plantlets that appear at each node. Underground modified stems are bulbs, corms, rhizomes, and tubers. These underground stems are often mistaken for roots. If you can see buds, leaf scars, or nodes, it an underground stem. And each of those nodes can produce several buds. The eyes of a potato are nodes. Pruning Nodes are important when it comes to pruning. It is just above a node where most cuts are made. To keep your plants healthy and productive, you want pruning cuts to be clean, smooth, and at a 45° angle, just above a node. You will also want to make sure that the node is pointing in the direction you want the new growth to go because it will. When you make this cut, all of the plant nutrients and hormones that had been directed toward continued stem growth will now be directed to the node, which will produce new growth. The same principles are applied when notching. Notching If you have a young fruit tree that isn’t putting out as many lateral branches as you would like, you can use notching. Notching is a method used two to three weeks before flowers appear to create a better structure. To notch a tree, first identify where branches are needed. Then, find nodes in those areas. Cut shallow notches one-third of the way around each branch, just above those nodes. By cutting through the phloem, the flow of auxins (growth hormones) will be redirected into the node, encouraging stem growth. Do not cut into the structural part of the branch. You should only notch a few nodes at a time, in case something goes wrong.
Plants use hormones, called gibberellins, to promote internode elongation, increase cell division, stimulate flower production, and regulate seed enzymes. Commercial growers apply gibberellins to plants to increase the size of Thompson seedless grapes, to end dormancy earlier than normal, and to force camellias to bloom out of season, among other things.
If you see internodes that are longer or shorter than normal for a plant at a specific stage of its growth, it can provide you with clues about its health. Shorter internodes can indicate low soil fertility. Longer internodes can mean the plant isn’t getting enough sunlight. This is called etiolation. Take a closer look at the plants in your garden to see where the nodes are and how the length of the internodes change. What’s happening at your plants’ nodes? Each spring, buds burst forth with new leaves, flowers, and stems. But sometimes those buds appear in unusual places. Normal stems produce one or more buds at nodes. Nodes are those small bumps you see along stems. The plant cells at nodes are different from plant cells elsewhere along the stem. Those cells are what make buds and leaves possible. We expect to see terminal buds at the end of stems and axillary or lateral buds along the sides of a stem. This is where a leaf is already connected, on a shoot node at the leaf axil. These are normal ways of growing buds for vascular plants. But adventitious buds are rogues and outliers. This can be to their advantage. It can also be risky. Adventitious buds turn up in strange places. You may find them along internodes, on leaves, in the callus of fresh pruning cuts, on new shoots, and even on roots. These buds are called adventitious because they take advantage of unusual opportunities. In response to injury When a plant is injured, whether through pruning, herbivore or insect feeding, fire, or mechanical injury, a whole slew of responses kick in to seal off the affected area. And sometimes the plant responds by trying to replace the damaged stems using adventitious buds. These buds may appear out from under the bark, at a pruning cut. They may pop up on the stump of a severed cactus.
As for the risks mentioned earlier, when a stem produces a lot of secondary growth, adventitious buds are often killed off. I have no idea who makes that decision or how it is carried out. I guess plants figure those outliers are expendable, as is often the case.
Which plants in your garden have adventitious buds? With a name like potato mop top, you know I had to dig deeper! I immediately pictured Carrot Top crossed with Mr. Potato Head. Ends up, it’s nothing like that. In fact, plants infected with potato mop top may look exactly like healthy plants. We’ll get to that in a minute. What’s strange about this viral disease is that it is spread by another disease. The powdery scab connection You know how when you catch a cold, you’re more likely to get a canker sore? Well, plants infected with powdery scab become a lot more vulnerable to the potato mop top virus (PMTV). Both diseases are caused by a Cercozoa [think amoebae] called Spongospora subterranea f. sp. subterranea. Imagine having to write that return address every time you sent a letter! Anyway, powdery scab is a type of slime mold that occurs in areas with poor drainage. When powdery scab is present, your potato plants are more likely to catch mop top. They can still catch PMVT without powdery scab, but it is not as likely, and infections that occur tend to be less damaging. Potato mop top lifecycle Potato mop top spores can remain viable in the soil for up to 18 years. All they need is some cool, moist weather and some potatoes infected with powdery scab to work their way into tubers and the root system. From there, they move into the xylem and travel throughout the plant, blocking the flow of water and nutrient-rich sap. And potatoes aren’t the only garden plants susceptible to this disease. Your tomatoes and groundcherries may also become infected. Other nightshade family members and plants in the amaranth family, such as beets and spinach, may also end up with potato mop top. Potato mop top symptoms Leaves of infected plants will show signs of yellowing and the internodes will be shorter. Internodes are the spaces along a stem between two leaves, buds, or stems. This creates a stunted, “mop top” appearance. Foliar (leaf) symptoms can vary widely. Some potato varieties may exhibit a bright yellow blotch pattern (aucuba pattern) in the lower leaves, while others may have V-shaped yellow patterns. When you cut into a potato infected with PMTV, you know something is wrong. You’ll see dark brown lines and spots throughout the tuber. Those symptoms are known as spraing. This damage looks similar to the alfalfa mosaic virus. You may also see deep cracks and skin distortions. What’s strange about potato mop top is that plants grown from cuttings of infected plants may not show any aboveground symptoms, but they will have even more infected tubers than the parent plant.
Potato mop top management The potato mop top virus is responsible for crop losses of up to 67% and it is a tough disease to control. There are no resistant varieties. Not yet, anyway, though russet-skinned potatoes seem to be less sensitive to PMTV. And there are no chemical treatments against viruses either. Commercial growers apply fungicides that contain fluazinam to the soil to control the long-winded amoeba-like creatures mentioned earlier. Fluazinam products are commonly used against late blight, another potato disease. Good sanitation and vector controls are really your only options when it comes to managing potato mop top. This means insisting on certified disease-free seed potatoes and nothing less. Plus, you can reduce the occurrence of powdery scab by improving drainage. The easiest way to do this is by mulching with a thick layer of free arborist chips. [My concrete-like clay soil is now loose, dark, and productive, thanks to free wood chips!] Other practices that help reduce the odds of potato mop top occurring in your garden include avoiding excessive applications of fertilizer that contain nitrate or ammonium nitrogen. These stimulate root growth, providing lots of tender new victims to both diseases. Also, allow the soil to dry out between waterings, especially early in your potatoes’ development. And wait until the soil is warmer to plant in the first place. This helps your potato plants be stronger and healthier from the start. And, as always, be sure to disinfect your garden tools regularly. If a plant becomes infected with potato mop top, it must be removed and thrown in the trash. What’s worse, you can never grow potatoes in that soil again. Ever. As spring approaches, I’m watching my potato patch as it starts waking up from its winter sleep. New shoots are beginning to appear and I am monitoring for signs of this and other diseases so I can nip them in the proverbial bud. (Sorry, I couldn’t resist.)
Symptoms of potato virus X
You may not see any symptoms at all, besides a drop in tuber production, and your plants may look bushier than normal. Or, you may see chlorosis, dead spots in tubers, leaf crinkling, mosaic, ringspot, and smaller leaves. [Sadly, I was unable to find any photos I could use.] Potato virus X management Potato X disease is not transmitted by insects. It is only spread mechanically, on tools, clothing, and infected roots and tubers. If you avoid walking through infected areas and only use clean, disease-free seed potatoes, you should be able to prevent this disease. Crop rotation can help break the cycle. Since potato X also appears on weeds in the same family, it’s a good idea to keep bindweed away from your susceptible crops. Heck, it’s always a good idea to keep bindweed out of your garden and landscape. Some potato varieties, such as Atlantic, HiLite Russet, Norwis, and Sebago, show some resistance to PVX, so you may want to use them in your potato patch. |
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