Ramularia leaf spot management

Infected commercial crops are sprayed with fungicides up to eight times a year with limited success. Of course, you need to wear protective clothing and limit the number of hours you spend around these chemicals, so you might want to think twice before applying them to your groceries.


Since stressed plants are more likely to become infected, keeping your plants healthy with these tips can prevent many problems:

• Avoid overhead watering or water early in the day.
• Dispose of infected plants in the trash, not the compost pile.
• Employ crop rotation.
• Invest in certified disease-free seeds and seedlings.
• Quarantine new plants.

Figuring out what leaf spots are telling you can be tricky, but it's worth the effort to find out.

​Many garden ornamentals, such as dahlia, fuchsia, lilac, marigold, and salvia are also very sensitive to ozone levels.


​If you live in an area with lots of ozone, you may want to focus your gardening efforts on somewhat resistant cucumbers and peppers. What else can you do?


Aside from working from home and walking to the store instead of driving, you can protect your plants by not giving them more fertilizer than necessary. Plants are most susceptible to ozone damage during periods of rapid growth.


Did you know that ozone smells a little like chlorine? I didn’t, either.

Plants are much more sensitive to the number of daylight hours than you might expect. For some plants, as little as one-minute exposure to a 25-watt bulb is enough to halt blooming. Strawberries are very light-sensitive. If they don’t receive enough darkness, you might not receive any berries.


The number of hours of daylight can also cause bolting, which can shorten the useful life of your lettuces and spinach. If bolting is a problem in your garden, you may want to turn off some of those lights.


Abscission and dormancy

As the days get shorter and the nights get longer, plants produce hormones used to protect themselves through the colder winter months. Those phytohormones tell plants to pull nutrients out of leaves and let them fall. If any part of that natural cycle is interrupted or interfered with, plants can be unprepared for winter weather, making them more susceptible to pests and diseases.


Night lights and insects

We all know that moths are often attracted to porch lights, but nighttime lighting attracts several other insects to our landscapes. Research from the University of Exeter has shown that night lights “trigger complex effects on natural food webs [and that they] may have more permanent, widespread impacts on wildlife and ecosystems.”


Managing light pollution

Now we know: too much light at night can adversely affect our plants. So it’s up to us to reduce light pollution (and air pollution) to improve the health of our plants and the food they produce for us. Try some of these tips to help reduce light pollution in your home and landscape:

1. Eliminate 24-hour security lighting and replace it with motion-sensor lights.
2. Turn off unused lights.
3. Use fewer lights both indoors and outside.
4. Close your curtains at night.
5. Turn off all lights when you go to bed.
6. Use night shift settings on all your devices.
7. Use dimmers and timers.
8. Point exterior lighting fixture straight downwards rather than at an angle. [Your neighbors will thank you, too.]
9. Use LED lights.
10. Reduce nighttime driving.

With a good night’s rest, you and your plants will both feel better.

It may surprise you, but rain gardens are a type of xeriscape.


Do you know any other edible plants that would grow in a xeriscape? 
Let us know in the comments!

How to grow bay laurel

Bay laurel plants can be grown from seed or cuttings. The easiest way is to buy a bare-root tree. These trees are dioecious, so some are male, and some are female. Since we mostly grow them for their leaves, this isn’t a problem. If you want berries, however, you’ll need one of each to get a crop.


These shrubs lend themselves very well to the home garden in USDA Hardiness Zones 8 through 10. You can also grow them as containerized indoor plants. A 5-gallon pot is big enough. Bay laurel prefers full sun to light shade. If grown indoors, it will need lots of bright direct sunlight.


Bay laurel prefers slightly acidic soil with good drainage. These trees benefit from wind protection, so select a site with that in mind. You can use bay laurel as a topiary, shaping and twisting it to your heart’s delight.


Bay pests and diseases

Bay laurel trees protect themselves against most pests and diseases. Soft scale (Coccus hesperidum) and jumping plant lice (Trioza alacris) are two insect exceptions. Phytophthora root rot and leaf spot and shot hole disease make also occur.


Yellowing leaves on bay laurel often mean they need more nitrogen. A lab-based soil test is a good idea.


Other laurels

And what about those other laurels? It is not safe to assume they are all the same. Some of them are poisonous. And others can be a real headache.

Tree roots may surprise you.

We used to think trees looked pretty much the same underground as they did aboveground. We once thought trees sent taproots deep into the earth to suck up water and nutrients and hold themselves upright. All of those things are true except for the first one. Now we know that most tree roots extend laterally far more than horizontally. Most tree root systems extend 4 to 7 times the diameter of the aboveground portion. The root system of a mature oak can extend up to 250 feet! We also know that they communicate and exchange nutrients with neighboring trees, but that's another discussion. Today, our garden topic is root plates.


What are root plates?

Root plates are the combined disk-shaped mass of roots and soil immediately surrounding the trunk of a tree. If you have ever seen a tree knocked over by a strong wind, you have probably seen a root plate. ​

How can we help our trees?

So, what can we do to keep our trees from falling over?

• Mulch 2-4 inches deep around trees, but not touching the trunk.
• Avoid rototilling or digging near trees.
• Top-dress around trees regularly with aged manure or compost to maintain healthy soil and provide food for your trees.
• Minimize heavy traffic directly under trees.
• Install trees where their roots won’t damage sidewalks, driveways, or building foundations and need to be cut.

Did you know that corn, sunflowers, and wheat have root plates? I didn't either.

How to grow nutmeg

You can grow nutmeg from seed or start with a seedling. If you get an untreated nutmeg fruit for growing, place it in a paper bag and put it in the refrigerator for up to 45 days. Stratification of the seed in cold triggers hormonal changes that help the plant grow properly. Soak the seed in water for 24 hours prior to planting. Then plant the seed one inch deep in loose, nutrient-rich soil. Keep the soil warm and moist. You should have a nutmeg sprout in six to eight weeks.


Nutmeg can be grown in a large container (10 gallons is ideal). If you put nutmeg trees in the ground and have more than one, space them 30 to 40 feet apart.


Nutmeg trees prefer hot, wet weather, neutral soil, and good drainage. You’ll need to keep the soil moist but not soggy. Dry soil and nutmeg trees don’t mix. Two inches of water each week is a good standard for these trees. And mulching around your nutmeg tree (but not touching the bark) will help retain moisture and stabilize temperatures.


Top dressing around your nutmeg tree with composted manure will provide many important nutrients. You can also use a standard fertilizer or fish emulsion.


Nutmeg trees grow best in dappled shade with four to six hours of direct sunlight and 77–86°F temperatures.


Nutmeg tree problems

Once established, nutmeg trees have few problems. Holes in seeds indicate cocoa weevils are present. Anthracnose leaf spot and thread blight are the two most common diseases. You can use a Bordeaux mixture or fixed copper to prevent both.


Many people have used nutmeg and mace from the grocery store, dried, ground, and bottled. Like many other edibles, homegrown or simply freshly grated, nutmeg and mace add new layers of taste and fragrance to your baking.

If grown from seed, it will take six years before you get a crop. You can also grow star anise from a branch cutting. These trees prefer loamy, slightly acidic soil (pH 6.0–7.5) and constant moisture. Your star anise tree will grow best with one inch of water each week, allowing the soil to dry out between waterings.


Top dressings of aged manure or compost can ensure your star anise gets the proper nutrients in spring and summer. Do not feed your tree in autumn or winter.


You can also grow star anise as a hedge, but it will require regular pruning because of how quickly it grows. Pruning star anise generates amazing smells!


Unripe fruits are harvested and left to dry. They can be stored for years in an airtight container.


Problems associated with star anise

Because of the oils that make star anise so fragrant, insect pests are not a problem for this tree. Alternaria blight and downy mildew, however, can cause problems. Use neem oil or fixed copper to prevent these problems.


Did you know that star anise used to be used to make Tamiflu? I didn’t, either.

Eggs are elliptical and pale yellow, larvae are white with dark heads, and pupae are small and cream-colored.


Palestriped flea beetle lifecycle

Mated females lay eggs in the soil near the base of food plants each spring. When they hatch, larvae move into the soil where they feed on roots for 2 or 3 weeks before pupating. Pupae match hatch mid-summer through early autumn. There can be up to three generations each year.


After pupating, adults emerge and begin feeding on the underside of leaves. As temperatures drop, adults look for sheltering dirt clods, plant debris, and weeds to protect them through winter.


Palestriped flea beetle damage

While the larvae chew on the roots, adult beetles are the ones that cause the most damage. Palestriped flea beetle feeding looks a lot like shot hole disease. It can also be mistaken for cavity spot. As beetles gnaw on the underside of leaves, the damaged areas die off and create small irregular holes. When this feeding occurs on seedlings and young plants, the damage can significantly reduce yield over the life of the plant or kill them outright.


How to control palestriped flea beetles

Pesticides generally don’t work against flea beetles. You can reduce the likelihood of them setting up shop in your garden by keeping attractive weeds away from your plot. By attractive, I mean members of the same plant families the beetles prefer. You can use that same logic turned around by employing trap crops to lure palestriped flea beetles away from garden plants you’d rather they left alone.


Monitor seedlings twice a week for signs of palestriped flea beetle feeding. Knock any beetles you find into a container of soapy water. Once plants are established, a little damage won’t cause significant problems.

Other members of the tea family have the same characteristics. A couple of North American natives are Georgia’s Franklin tree (Franklinia alatamaha), which is now extinct in the wild but still cultivated as an ornamental, and Loblolly-bay (Gordonia lasianthus), found throughout southeastern North America are both members of the tea family. But what about that cup of tea?


Tea plant basics

Tea plants (Camellia sinensis) are evergreen shrubs that can grow six feet tall. They have deep taproots and use a lot of water. This makes sense because their native regions get an average of 50” of water a year. Those regions are also a lot warmer than, say, Minnesota. Tea plants can be grown outdoors in Zones 7-12 or indoors year-round. Because tea plants have large taproots, they need large containers.


There are four unique tea plant varieties. Chinese small leaf tea (C. sinensis var. sinensis) and Chinese large leaf tea (C. s. var. assamica) are the most commonly grown tea varieties. There are thousands of cultivars.


Tea plants grow more slowly and produce the best flavor at higher elevations. They prefer moist, nutrient-rich, slightly acidic soil with a pH of 5.5 to 6.5 and full sun. It may take 4 or 5 years of growth before you start harvesting leaves from your tea plant, but it will grow and produce for another 40-100 years.


Harvesting tea leaves

Harvesting tea leaves can be a labor-intensive process. Young tea plant leaves and terminal buds (flushes) are harvested by hand to make high-quality tea. Lesser teas are harvested by machine. Depending on the local climate, harvesting may occur twice a year or as often as every week or two.


After being picked, leaves are allowed to wilt for a while. Then they are bruised or torn. Among professional tea producers, they are disrupting or macerating the leaves. Damaging the leaves this way allows enzymes to start oxidizing or breaking the leaves down. Next, leaves are rolled between human hands or crushed by machinery. Then the leaves are heated to halt oxidation. This process is called the green kill. The leaves are then dried completely, packaged, and sent to grocery stores, restaurants, and tea shops.


Tea plant problems

Tea plants are susceptible to bacterial diseases, including crown gall and bacterial canker. Nematodes and caterpillars commonly attack tea plants. But the biggest threat to tea plants comes from fungi. Anthracnose, armillaria root rot, black rot, and damping-off are a few fungal diseases that strike tea plants.


Like camellias, tea plants make lovely additions to tea gardens, patios, and sunny rooms, depending on where you live.

Check your milkweed plants regularly for those tiny black specks. And remember, if you are planting milkweed for monarch butterflies, be sure to plant native varieties, not tropical varieties. It matters a lot if you’re a monarch.

Large yellow underwing lifecycle

Adult moths generally fly from July to September, but those flight patterns have expanded in recent years. Females lay clusters of tiny, pearl-like eggs in the soil or on host plants. If you were to look closely, you would see that these eggs look ribbed or have a netting pattern.


Eggs start white but soon turn grayish-pink. After they hatch, these tiny caterpillars may feed a little bit, but the real damage occurs as temperatures rise. Just when your tomato, spinach, and strawberry plants are coming to life, cutworms emerge at night, devouring young leaves and severing new stems. After eating their fill, they return to the soil. There, they surround themselves with hard, rust-colored oblong cases where they pupate. Adult moths emerge 2-3 weeks later, and the cycle begins again.


Host plants

Adult large yellow underwings are attracted to butterfly bush, ragwort, and red valerian. But it is larval feeding that causes all the damage. Larvae feed on the stems and leaves of young plants. The following plants (and other members of the same families) are commonly used as food by large yellow underwing larvae:

•   Beets (Beta)
•   Broccoli and cabbage (Brassica)
•   Carrots (Daucus)
•   Grapes (Vitis)
•   Lettuce (Lactuca)
•   Rhubarb
•   Spinach
•   Strawberries (Freesia)
•   Tomatoes and potatoes (Nightshade family)

Carnations, chrysanthemums, dahlias, dandelions, freesia, gladiolas, sweet violet, and grasses are also vulnerable to cutworm feeding. But planting calendula in your garden will help to deter these pests.


Controlling large yellow underwing moths

These flying pests are attracted to lights at night. If you feel so inclined, you can sit on the porch with a butterfly net and put an end to their destructive ways with a container of soapy water or a garden shoe. Or, you can go out at night with a flashlight and handpick the buggers before too much damage is done. You might also use a garden claw to gently disturb the soil around affected plants. The larvae tend to stay near the surface, so you may be able to find and remove those pests that way. Drench tests can also flush cutworms out of the soil.

Lectins as toxins


The toxic warfare response may be what triggered Mr. Gundry's belief that lectins cause human disease. Lectins are toxic in specific situations. They are the reason why beans and other legumes are difficult for us to digest. That’s why we cook them. The heat breaks down the lectins (among other things).



Can lectins hurt me?

Some plants contain enough lectin to cause illness or even death. Castor oil beans are one example - but who wants to eat those? ​

In most cases, we typically can not eat enough lectin-containing plants to hurt us. 


As always, take sensational media with a grain of salt. And cook your beans.

PAN is second only to ozone in its toxicity to plants. As a type of air pollution, it is especially hard on smaller plants and young leaves.


What is PAN?

PAN is created when sunlight hits car exhaust and industrial gases. We won’t get into the chemistry of it or the different types of PANs. It’s enough to say that hydrocarbons interact with nitrogen in the air, creating problems for plants. PANs occur in high-traffic areas such as Los Angeles, but their effects are felt all along the western U.S. seaboard and in many other industrialized regions.


​Vulnerable plants

Like other garden issues, not all plants are affected equally. Beets, cane fruits, celery, dill, endive, escarole, fennel, lettuces, melons, oats, peppers, pinto beans, potatoes, spinach, sunflowers, Swiss chard, and tomatoes are all vulnerable to PANs in the air. If you live in an area where PAN might be a problem, broccoli, cabbages, corn, cucumbers, lima beans, onions, radishes, sorghum, and wheat should perform better than more sensitive plants.

PAN can combine with ethylene to make matters worse. Healthy plants produce ethylene as part of the ripening process. But ethylene is also found in vehicle exhaust and industrial fumes, which means there is often too much of it available. Ethylene acts as a plant hormone. And we’ve all seen what happens when people take too many steroids.


Symptoms of PAN combined with ethylene include downward leaf and stem curling (epinasty), inward petal curling and the failure of buds to open (sleepiness), and stunting. Color breaking in blossoms and early petal drop may also occur.


Bottom line: air pollution is bad for all of us.

Predatory mosquito development

Predatory mosquitos start out like other mosquitos. White, football-shaped eggs are laid in tree cavities and other spaces that contain water. They also use all the other stagnant waters that pesky mosquitos use: flower pots, pet watering bowls, patio furniture, and tires. Mosquito eggs are the size of a grain of sand.


The eggs hatch into larvae. Predatory mosquito larvae go through four growth stages or instars. As they grow, they feed on anything nearby that moves, including each other. And this presents a problem.


The problem with predatory mosquitos is that you generally haven’t been able to buy them. Unlike our cheery ladybugs and voracious praying mantis, predatory mosquitos don’t take kindly to mass commercial breeding programs. They simply eat each other. Instead of hundreds of helpful predators, you’d end up with a handful of overfed gluttons. Scientists are working on this. For now, the best thing you can do is maintain a healthy environment with lots of biodiversity and use pesticides judiciously.


While Bacillus thuringiensis (Bt) will kill biting mosquitos, it doesn’t seem to affect their predatory cousins.

Plants need clean air to grow and thrive too. But it can be hard to recognize the damage caused by air pollution. It often looks like disease, heat stress, mite feeding, nutrient disorders, or water stress. If you’ve ruled those out, it’s time to consider air pollution.


​Types of air pollution

Air pollution is estimated to cost US agriculture over one billion dollars annually. This damage can be chronic or acute. The smoky yellow skies from fires or fumes from a chemical spill fall under the acute category. More likely, your plants are feeling the effects of long-term exposure to low levels of pollutants from industry, power generation, and vehicles. The most common pollutants include nitrogen oxides, ozone, peroxyacetyl nitrate (PAN), and sulfur dioxide. Ammonia, chlorides, chlorine, and fluorides may also be in the mix that’s choking your plants.

Protecting your plants

Healthy plants are more able to protect themselves, so keep them well fed and watered. Also, the damage is most likely to occur during warm, humid days with no wind. Monitor air quality in your area and give your plants a light shower from the hose on days with poor air quality.


You can also help your plants (and yourself) by learning about the industries currently or recently active in your area (or upwind). And think about how you spend your money. Are you supporting companies that protect the environment or opting for the cheap stuff? It’s up to you, but we're all breathing the same air as our plants. Just sayin'.

Where to grow tree collards

Tree collards should be three feet apart. And they will readily cross-pollinate with other members of the cabbage family. Tree collards grow best in nutrient-rich, slightly alkaline soil.


Tree collards thrive in dappled shade and prefer protection from afternoon sunlight. They do not grow well in full shade.


Tree collards are relatively drought tolerant but perform best in well-aerated soil with regular mulching and top dressing. And they’ll grow bigger and better with regular irrigation in summer. It’s always a good idea to have your soil tested by a reputable lab before fertilizing. Adding too many nutrients can cause more problems than nutrient deficiencies.


Tree collards pests and diseases

These plants are relatively trouble-free. Imported cabbageworm butterflies are the primary pest of tree collards. Handpicking the caterpillars and extermigating the eggs are your best control methods. Snails and slugs are less of a problem than seen on their shorter cousins. And aphid infestations tend to be localized and short-lived. Let the ladybugs and other beneficial insects take care of those pests for you. Ladybugs won’t be able to do anything about the deer and other herbivores, though.


Powdery mildew is a common problem for tree collards, so maintain good airflow and keep your plants healthy.


To keep your tree collards attractive and productive, it’s a good idea to prune out stems as you harvest leaves. If you want your tree collards to reach full height, you may want to stake them upright. When growing naturally, they tend to fall over, creating an arching tangle similar to a blackberry bramble.

We’ve all heard social networks help us to be healthy and successful. It ends up that trees have been networking quite intimately for a very long time.


Tree networking takes two forms. They frequently share nutrients indirectly, using soil microorganisms as go-betweens. And they fuse their root systems in natural root grafts, called anastomoses.

How do roots graft?

Natural root grafts occur when relatively small roots of two different trees come into contact with each other. As they grow, they fuse, creating mutually accessible cambium layers and vascular bundles that allow them to share water, nutrients, and the products of photosynthesis. 


Why does this happen?

More than 150 plant species exhibit natural root grafts, according to researchers. There is debate about whether this occurs due to overcrowding or if plants purposefully graft their roots onto neighboring roots. There is also debate whether this action is beneficial or verging on parasitism. Most researchers lean toward the mutually beneficial explanation. Potatoes and strawberries frequently graft their roots onto neighboring plants of the same species. Surprisingly, some natural root grafts are between different species.

Benefits of natural root grafting

Natural root grafting provides several benefits to all parties involved. Those benefits include improved stability and water and nutrient sharing. These benefits help keep neighboring trees healthy, making them more resistant to wind and herbivore damage. In one study, trees with natural root grafts were found better able to recover from a spruce budworm attack.


Tree root grafting allows groups of trees to share water and nutrients. It also forces them to share soil-borne pests and diseases, such as Dutch elm disease and apple proliferation. 


For me, this is yet another example of the amazing processes going on underground. I was stunned to learn that plants can hear. I wonder what will be discovered next.

Plants respond to heat

When plants are hot and dry, they protect themselves by closing pores found on the underside of leaves. These stomata control the rate of gas exchanges used by plants in photosynthesis. This respiration can be slowed by as much as 50% during periods of extreme heat. Unless your plants are drunk.


Pints and plants

Recent research has found that many plants can thrive during drought if they are given ethanol. Ethanol is alcohol. It ends up that plants produce alcohol when they don’t have enough water. This fact led some researchers at the RIKEN Centre for Sustainable Resources Science to wonder if the same processes could be used to protect plants.


Alcohol abundant and cheap to make. Did you know that U.S. bars mark up their alcohol by an average of 400-500%? But back to the plants.


Researchers compared wheat and rice plants that had been treated with alcohol to those without. The plants were deprived of water for a couple of weeks in summer. Only 5% of the untreated plants recovered, while 75% of the alcohol-treated plants were able to resume growing once watered. Those are some significant numbers!


The scientists radio-tagged the alcohol so that they could see where it went within the plants. Plants that were given alcohol started behaving like they were in a drought even before the water was cut off. This helped them to be better prepared than their teetotaling brethren. Not only did they make better use of the water they had, but they also used the alcohol to create sugars to provide themselves with energy and perform more photosynthesis, even though their stomata were closed.


Now, this doesn’t mean you should go around giving your pumpkin plants shots of tequila. That would be a bad idea. What it does mean is that an occasional spilled beer might not be such a bad thing and we should all be on the lookout for more specific instructions as the research continues.

Bacterial soft rot destroys more crops than any other bacterial disease.


Commonly occurring in cruciferous, cucurbit, nightshade, and onion families, bacterial soft rot also causes severe pitting in carrots.

Symptoms of bacterial soft rot

Like other bacterial diseases, bacterial soft rot is easily overlooked at first. As the disease progresses, water spots start to form on soft tissues. Unlike the whitish splash marks left on old wooden furniture, these spots grow larger, softer, and start to sink. As interior tissues break down, these damaged areas may ooze and start changing color. Discolorations can range from cream to black. And they smell bad.


Bacterial soft rot management

Poor drainage, waterlogged soil, and insufficient airflow all set the stage for bacterial soft rot. Infected plants must be destroyed and removed. Prevention is worth the effort. The following good cultural practices can significantly reduce the likelihood of bacterial soft rot affecting your plants:

•  Use certified clean seeds and seedlings.
•  Quarantine and harden off new plants.
•  Install resistant varieties.
•  Plant at the appropriate times and correct depths.
•  Use recommended plant density.
•  Monitor plants regularly for signs of infection.
•  Provide adequate airflow through proper pruning.
•  Irrigate properly, allowing the soil to dry out between waterings.
•  Employ crop rotation to reduce overwintering bacteria.
•  Remove weeds.
•  Avoid working crops when they are wet.
•  Remove infected plants and dispose of them in the trash.
•  Clean and disinfect tools regularly.


If bacterial soft rot continues to be a problem in specific areas of your garden, use that space for plants that are generally not susceptible. That list includes beets, corn, and snap beans.