Now that I live in an apartment, I find myself missing the fresh figs and nectarines, abundant almonds, and deluge of citrus from my old trees. And that got me thinking about putting a small fruit tree on my balcony. It ends up that you can grow a surprising number of fruit and nut trees in containers.
Following the same advice I gave in my post on container gardening, we’ll need to select a food-safe container with good drainage, fill the container with potting soil, and make sure the tree gets enough sunlight. But which trees can be grown in containers? And how big do the containers need to be? Let’s find out.
Tree containers and soil
Back in California, I had a friend who was growing an orange tree in a two-foot wooden planter box. The tree was 20 years old, less than three feet tall, and very productive. It can be done. The most important things to keep in mind when selecting a container for your tree are drainage, durability, and food safety. Too many planters out there are made of toxic materials. Make sure your tree’s home is made of food-grade materials and that there are drainage holes in the bottom of the pot. You’ll need a 10- to 15-gallon pot.
Tree roots can be surprisingly strong. I’m sure you’ve seen sidewalks that can attest to that. Your tree’s container needs to be durable enough to withstand tree roots and temperature extremes. Lightweight plastic may be easier to move around, but it probably won’t last as long as your tree.
Once you have a container, you’ll want to fill it with potting soil, not planting soil or topsoil. Topsoil may contain pests or diseases that may cause years of headaches and it won’t drain properly in a container. Planting soil is meant for the ground and doesn’t drain the way your potted tree will need. Potting soil is specifically engineered to help plants thrive in containers. And please don’t put rocks in the bottom of planting containers. All they do is take up space better allocated to soil and roots.
When you fill your container with potting soil, create a mound in the center of the pot. You will arrange the roots of your tree over that mound and then cover them with soil. Do not tamp down the soil. Instead, mud in your new tree to prevent damaging tender roots, making sure that the graft union is visible above the soil line. Remember that improper tree planting depth is one of the worst things you can do to your tree. Be sure to install a tree support until your baby tree has had a chance to send out supporting roots, then remove the support.
Which trees can be grown in pots?
Preparing for my trek across Spain, I saw this olive tree in Paris. Based on the trunk, I’d say it was a very old tree living in a rather small container. But it looks healthy, so you can certainly put olives on your list of possibilities.
Generally speaking, you will want to choose a dwarf variety tree. These are trees grafted onto M-9, M-26, M-27, or P-22 rootstock. Larger varieties will be okay in a container for a while, but they will need to go into the ground eventually. And transplanting a tree is no small feat. Which reminds me, containerized trees can live for 20 years or more. Because of this, it’s a good idea to have a plan in place for up-potting your tree, should that ever become necessary. Personally, I’m going to start with a full-sized container so that I can avoid that Herculean task.
To get the most out of your containerized fruit tree, you may want to get a fruit cocktail tree. These are trees that have different types of fruit grafted onto the branches. For example, a fruit cocktail stone fruit tree can produce apricots, nectarines, and peaches on the same tree. Or, you may select a 4-in-1 cherry tree with four different varieties of cherries growing on the same tree. It really helps make the most out of small spaces.
When shopping for rootstock, look for self-fruiting varieties, or you’ll need more than one tree to get fruit. Whichever tree you select, make sure that it is suited to your USDA Hardiness Zone. If you absolutely must have that dwarf lime (Zones 9-10) and you live in Grand Rapids, Minnesota (Zone 3a), you’ll have to bring it indoors for the winter, so make sure you have a plant stand with sturdy wheels. Or, you can keep it indoors and hand-pollinate. In either case, your potted fruit or nut tree will need at least 6 hours of sunlight each day.
Other factors to consider when selecting your potted tree are chill hours and local pests and diseases. One of the first things I noticed about Seattle when I arrived last summer was the number of plants affected by powdery mildew. And the few plants I put on my balcony were soon populated with stink bugs. (And I’m on the 7th floor!). Fruiting trees need a certain number of chill hours each winter to trigger fruit production in spring. As always, be sure to buy certified pest- and disease-free rootstock.
Caring for potted trees
Containerized plants need to be monitored regularly to make sure they don’t dry out too much in summer. You can encourage root growth by watering your potted tree from the bottom, rather than the top. Simply add water to the tray under your pot. The soil will absorb the water and the tree roots will extend downward to access that water. You will also need to feed your tree regularly.
So which tree am I going to get?
My balcony faces north and I live in Hardiness Zone 8b. Luckily, my balcony gets lots of sunlight and Seattle usually gets 3,000 chill hours each winter. My next step is to figure out which tree is least likely to attract or be affected by powdery mildew or stink bugs.
I found a website dedicated to thwarting invasive brown marmorated stink bugs (Stop BMSB) and learned that these pests love almond, apple, apricot, black walnut, cherry, fig, hazelnut, olive, peach, pear, pecan, and pistachio trees. They also feed on beans, cabbage, cayenne peppers, collards, cucumbers, horseradish, persimmons, soybeans, summer squash, sunflowers, and Swiss chard. Darn! It looks like my balcony garden is going to have a stink bug problem no matter what I grow! Luckily, fruit trees are mostly resistant to powdery mildew.
Based on where I live, the amount of sun exposure available, and all the rest, I think I am going to opt for a dwarf multi-variety cherry or plum tree for my balcony. Now if I could only find one that isn’t already sold out! Which tree are you going to plant?
Planthoppers are not leafhoppers, though they have much in common. Most important, both spread disease as they siphon sap from plants.
Planthoppers as disease vectors
Planthoppers are responsible for transmitting several diseases, especially those caused by phytoplasmas and viruses. One planthopper species nearly wiped out Jamaican Tall coconuts by infecting trees with lethal yellowing. Planthoppers often transmit X disease to cherries and other stone fruits. They are also responsible for spreading cereal tillering disease, maize mosaic, and several other diseases.
There are more than 12,500 planthopper species (Fulgoroidea), and they occur worldwide. With so many species, it’s no surprise that they come in several shapes, sizes, and colors. Spotted lanternflies and buffalo treehoppers are types of planthoppers. Snowy planthoppers look like whiteflies.
As their name indicates, these insects can launch themselves from one place to another. They do this the same way grasshoppers do. More often, however, they walk very slowly. But that’s not what makes them so hard to see.
Planthoppers often look like leaves or other plant parts. You can look right at one and not see it. Generally speaking, planthoppers hold their wings vertically, like butterflies, and their bodies are flattened. Nymphs produce a waxy substance that protects them from water and predators. Adult females also produce this wax and use it to protect their eggs.
Planthoppers are sap suckers. As they feed on practically all of your garden plants, they produce a sugary poop called honeydew. Sooty mold thrives on honeydew. So do ants. In fact, ants are known to tend planthopper larvae, protecting them from predators. The larvae of some planthopper species live underground and feed on plant roots or fungi.
Planthoppers can be difficult to control because of their mobility. Many people recommend spraying them with a blast from the hose. I imagine this would take care of the nymphs who would be unable to return to their food supply, but I can’t imagine it would be very effective against adults. I could be wrong. Luckily, they are attracted to yellow sticky sheets. And predatory stink bugs feed on planthopper larvae.
Did you know that some planthopper species communicate with their neighbors through vibrations in plant stems? I didn’t either.
Also known as cherry X disease, peach X disease, and cherry buckskin disease, X disease makes fruit small, pale, and bitter. It can affect stone fruits, such as apricots and cherries. Once a tree is infected with X disease, it must be removed to prevent the infection from spreading to other trees.
What causes X disease?
X disease is caused by phytoplasma. Phytoplasmas are microscopic, one-celled bacteria that have no cell walls or nuclei. To me, that’s just weird. Animal and plant cells and most bacteria have clearly defined cell walls that hold their insides in, where they belong, and a central nucleus that runs the show. I have a hard time wrapping my brain around these phytoplasmas. Maybe they are like parasitic amoebas, even though amoebas are animals. But I digress.
So how does a cell with no wings, legs, feet, or brain find its way to our fruit trees?
The answer is phoresy. Phoresy describes the relationship between two organisms in which one player is a hitchhiker but not a parasite. There are some pretty bizarre examples of phoresy. You may want to check it out.
Phytoplasmas catch rides inside sap-sucking leafhoppers, planthoppers, and psyllids without harming their hosts. When a cherry leafhopper feeds on an infected plant, the phytoplasma responsible for X disease is sucked into the insect’s gut with the sugary sap. When that vector moves to an uninfected plant and begins feeding, the pathogen is transferred to the new plant, causing infection.
What does X disease look like?
This disease can take up to 9 months to appear after infection occurs. Eventually, trees infected with X disease produce pale fruit that is small and leathery. Symptoms are commonly seen on only one branch at first. The leaves on infected branches may appear bronzed and small. Older leaves tend to fall off. Beyond that, symptoms can vary, depending on the tree species.
X disease is often mistaken for root rot. To figure out which it is, look closely at the graft union. That’s where the rootstock was grafted onto the fruiting stock. Pits and grooves are visible near the graft union if it is X disease. Cut into the wood and see brown areas in the phloem. These other symptoms of X disease are also common:
The fruit from infected trees tends to be pale, pointed, small, and nasty.
X disease hosts
There are two types of X disease hosts: those that don’t mind the infection (reservoir hosts) and those who succumb to the disease (non-reservoir hosts). Reservoir hosts are a problem because they look perfectly healthy but provide a source of infection to many important fruit and nut trees in our landscapes. Almond trees, chokecherries, sweet and sour cherries, Japanese plums, clovers, and dandelions are all reservoir hosts. [Dandelions?!!? Yes, dandelions.]
Nectarines and peaches can also become infected with X disease but are non-reservoir hosts. This means that they can catch the disease but not spread it. Scientists don’t yet understand how that happens, but they’re working on it.
X disease management
Since scientists have been unable to reproduce the phytoplasmas responsible for this disease in the lab, there are currently no treatments for this fatal disease. To reduce the likelihood of X disease occurring in your landscape, do your best to manage the insect pests responsible for carrying the pathogen.
The insects that spread X disease are often found on beets, burclover, ceanothus, curly dock, hawthorn, and pyracantha. Because of this, it is a good idea to maintain some distance between these plants and vulnerable trees.
If you suspect X disease has infected one of your trees, get help. Contact your local Master Gardeners or the Department of Agriculture for verification. They can also help you figure out the safe removal and disposal of infected trees.
Cherry leafhoppers are easy to miss, but they can cause big problems.
I can’t deny that leafhoppers are fascinating creatures because they are. I just don’t want them anywhere near my plants.
Cherry leafhoppers (Fieberiella florii Stål) are ¼” long and wedge-shaped. They have wide, flattened heads and narrow, upright rear ends. Depending on what they eat, where they are, and their developmental stage, they may be grayish-brown, green, orange, or tan.
Here is a list of the many diseases that can be spread by cherry leafhoppers:
They also leave collections of white crystalline frass on apples, pomegranates, and stone fruits.
Cherry leafhopper lifecycle
Leafhoppers lay their eggs in soft plant tissue where they are protected through the winter. Nymphs may also overwinter in tiny hideaways. Come spring, the eggs hatch, and nymphs go through several molts before reaching adulthood. These pests are most active during the hottest months of summer.
Leafhoppers are best managed with insecticidal soap.
No, we’re not discussing those yummy chocolate cherry cookies, though I may have to try baking a batch after researching this post!
The cherry crinkle we are exploring today is a condition that occurs in cherry trees. Cherry crinkle looks like a viral disease, but it’s not. Also known as cherry vein clearing, this condition is believed to be a genetic mutation that may or may not be related to a boron deficiency.
Cherry crinkle symptoms
Vein clearing, especially in the margins, is the most common symptom of cherry crinkle. Vein clearing refers to the way veins look lighter or more yellow than normal. I wasn’t able to find a photo that I could use, but these other symptoms may also occur:
Cherry crinkle management
If you suspect cherry crinkle, send a sample of soil to a lab for testing. This will tell you if your boron levels are low. It’s not a good idea to add nutrients without a soil test because too much of a nutrient can cause just as many if not more, problems as a nutrient deficiency.
If boron isn’t the problem, the tree is probably a mutant and should be replaced.
Cherry crinkle can be spread to unaffected trees by grafting mutated scions onto healthy wood. When shopping for a cherry tree, try to find one listed as unlikely to crinkle.
Parasites feed on other organisms. Aphid parasites feed on aphids. Let’s see what we can find out about these tiny garden helpers.
Aphid parasites (Aphidius colemani) and greenhouse aphid parasites (A. ervi) are parasitic wasps, but you don’t have to worry about getting stung. These native North American braconid wasps are more interested in aphids, honeydew, and nectar.
Aphid parasite description
Aphid parasite adults are black or brown with a narrow waist. They have yellow legs and long antennae. These tiny predators are only 1/10” long, which means you could put 7 or 8 of them in a line across the top of an American dime. You’ll probably never see aphid parasite larvae. They are very tiny and white, grub-like creatures.
Aphid parasite lifecycle
Females only mate once. After mating, they fly in search of aphid hosts for their young. Aphid parasites insert single eggs inside 100 aphids, and their greenhouse cousins lay up to 300 eggs. When those eggs hatch, the larvae eat their host aphids from the inside out. Ouch!
Aphid parasites often cut holes in the underside of their hosts to attach anchoring threads to a leaf. After about a week, these parasitized aphids swell up like balloons and turn beige to brown. These puffed-up aphids are called mummies. The larvae pupate inside the aphid and emerge as adults, ready to continue the cycle.
Surviving aphids frequently emit “alarm” pheromones that cause neighboring aphids to jump ship, abandoning the host plant and falling to the ground where they often die of starvation. Just as well.
Adult aphid parasites only live for 2 or 3 weeks, feeding on aphid honeydew and nectar from small flowers, such as anise, dill, mustard, and parsley. Their offspring can parasitize a large number of aphids. Aphid parasites are most active when temperatures are between 64°F and 77°F. They prefer green peach aphids and melon aphids for their supper but eat other aphid species, too.
Aphid parasites are available commercially and are frequently used to control aphids in greenhouse environments. You can attract and maintain habitat for aphid parasites by planting clumps of rye or barley. These plants attract aphids, providing a long-term food source for your aphid parasites. You can also add the flowers mentioned earlier. Because aphid parasites can fly, they will regularly scan your garden for all sorts of aphids. You should start seeing aphid mummies 10 to 14 days after releasing these hunters into your garden.
A midge is a small fly. Most midges are food for frogs and swallows. Many of them eat debris and help with nutrient cycling. Two of them, sand flies and black flies, bite and are vectors for disease. But, aphid midges deserve our notice and appreciation. They eat aphids. They eat a lot of aphids. Once you see how tiny these predators are, you may wonder how they do it. Let’s find out.
Aphid midge description
Adult aphid midges (Aphidoletes aphidimyza) are only 1/8 inch long. This means that you could line up half a dozen of them across the face of an American dime. Aphid midges can be mistaken for large fungus gnats or small mosquitoes. This is understandable since they are all members of the Diptera (two-winged) order, but mosquito wings are thinner than aphid midge wings.
Aphid midge larvae look like tiny orange slugs.
Aphid midge diet
Aphid midges feed on more than 70 different aphid species, including the dreaded green peach aphid. And it is the larvae who eat the most. They do this by injecting a paralyzing toxin into the leg of their prey. Then they suck the life juices out through a hole they have chewed in their prey’s thorax, the middle portion. Because their prey is paralyzed, aphid midge larvae can kill insects much larger than themselves. In fact, aphid midges are known to kill more prey than they can eat, but we won’t hold that against them. Aphid midge larvae kill up to 65 aphids each day.
Working with aphid midges
February may feel too early to consider aphids (unless you live in the Southern hemisphere). But it’s never too soon to learn how to help your garden plants stay healthy. As temperatures rise, you may want to buy aphid midge pupae to help in your fight against aphids. Pupae arrive in the mail in containers filled with moist vermiculite or peat. Depending on the temperature, pupae emerge as adults in 3–7 days. This is important. You’ll want to time your aphid midge release to coincide with newly emerging aphid populations. If you release them too early in the season, they’ll run low on food.
Before you squish another cluster of aphids, you may want to take a closer look to see if aphid midges aren’t already at work.
Blackheart is a disorder caused by environmental conditions. It occurs in celery, potatoes, sweet potatoes, tomatoes, and other garden crops. The causes of blackheart are the same. If seen in almonds, it’s a fungal disease called Verticillium wilt.
Causes of blackheart
Blackheart is the result of insufficient oxygen or too much CO2. How can you control those levels, you might ask. It’s easy. Picture this: it’s a hot day. Your plants are wilting. You add water, a lot of water. Your intentions are good, but now the ground is saturated. This localized flood pushes oxygen out of the macropores and micropores of the soil, and blackheart takes hold. Blackheart is also caused by too many cold days, like in your refrigerator.
Blackheart of celery
If young tissues in the middle of your celery plants turn black, it may be blackheart. Much like blossom end rot of tomatoes and tip burn of lettuce, this condition is a calcium uptake problem. It means plants cannot access enough of it. It may be a calcium soil deficiency or insufficient water. An inexpensive lab-based soil test is the only way to know what is in your soil. Irregular watering, soil salinity, and excessive fertilizer, specifically magnesium, nitrogen, or potassium, can interfere with calcium uptake.
Blackheart of tomatoes and potatoes (sweet and otherwise)
Commonly affecting potatoes and tomatoes, blackheart causes them to turn black in the middle. Fruit suffering from blackheart looks perfectly normal on the outside. Like hollow heart, which creates cavities within tubers, blackheart creates dark areas with distinct edges inside the fruit.
These darkened areas start as random spots that can expand. There may be small cavities, but they are mostly absent. These symptoms are similar to soft rot and Phytophthora root and stem rot, except that the interior stays firm. Eventually, these darkened areas will rot. If your seed potatoes have blackheart, they will grow into weak plants, if they grow at all.
To prevent blackheart from occurring, use these tips:
I hope the only blackhearts you have to deal with are the ones found in comic books.
Sometimes things look fine on the outside when the inside is damaged.
If you cut a beet, potato, seed, or watermelon in half and find a hole in the center, it has hollow heart. Also known as hallowheart, this condition indicates that the plant faced more stress than it could handle.
Hallowheart of watermelons
Hollow heart in watermelons is a pollination problem. Poor pollination occurs when temperatures are low or when there are not enough pollinators in the area. Somehow, poor pollination causes the interior of watermelon to develop triangular, often symmetrical gaps in the fruit. Seedless watermelons are more susceptible to hollow heart than seeded varieties, and orange and yellow-fleshed watermelons are the most likely to develop this condition. Improve pollination rates in your garden by attracting pollinators with flowers that appeal to honey bees and bumblebees. You can offset low temperatures with row covers.
Hollow heart in watermelons can also occur when they get too much fertilizer and insufficient water. The cells responsible for producing fruit cannot keep up with the cells producing rind under those conditions.
Hollow heart of beets
If you cut into a beet and find an empty center, it’s time to send a soil sample to a lab for testing. Hollow heart in beets is commonly a symptom of a boron deficiency. Look closely at the petioles (leaf stems) for signs of cracking, abnormalities, or stunting. If the cavity is rotting, it may be black heart.
Hollow heart of potatoes
Hollow heart in potatoes can be a weather problem or a water problem. Potatoes are greedy plants. They need a lot of water and nutrients to produce those fat tubers. Hollow heart occurs when a developing potato is hit with cold weather, followed by hot weather. Or when a sudden dry spell ends with an extended wet period. Like that one time you forgot to water them and then gave them extra water to make up the difference.
Where the cavity occurs will tell you its cause. Water or nutrient stresses that occur later in the growing season create holes at the bud end of the tuber. These cavities do not have a brown center. When hollow heart appears at the stem end of a tuber, cold weather followed by hot weather is the culprit. Brown centers are a common symptom of stem end hollow heart.
Hollow heart in seeds
Garden peas and other seeds can also develop hollow heart when unusually high temperatures occur right after germination begins. Because this disorder happens so early in the plants’ development, it leaves them vulnerable to several fungal diseases. The best way to avoid hollow heart in peas and other seeds is to plant at the optimal time of year for each species.
Bottom line: regular irrigation, planting at the appropriate time, and the right amount of nutrients can help prevent hollow heart in your garden.
Walking a garden path has long been known to soothe the soul.
Today, we are exploring that idea in more depth. Can a garden be designed with healing in mind? I think so.
We’ve already looked at several garden designs and themes. We’ve learned about scent gardens, sensory gardens, and tranquil gardens. Each of these can help us deal with emotional hurt and trauma. But how do they help us? How can we create a garden space that helps us deal with life’s difficulties? Let’s find out.
How gardens help us heal
Traumatic events can take many forms. Assault, betrayal, death, illness, and the mind-numbing exhaustion that comes from dealing with a global pandemic all have one thing in common: they create a sense of helplessness. According to trauma expert Robert Stolorow, trauma creates a “dreadful sense of estrangement and isolation” that leaves us feeling disconnected and out of control.
Gardening helps us deal with that sense of helplessness because we have some level of control. There is little risk. Like a beloved pet, our garden plants accept us exactly as we are, without judgment. They don’t hurt us. Gardens offer the possibility of a better future, even if that future is nothing more than a germinating seed.
Spending time in a garden brings us back in touch with natural cycles. No matter what we have gone through, spring bulbs bloom, summer squash grows, and the seasons advance as they always do. This helps ease our natural fight/flight/freeze response. The sights, smells, textures, and sounds of a garden reassure us on a lizard-brain level.
The act of gardening resets us physically. Bending, pulling, breathing, reaching—blood flows to our brains, our muscles, helping us think more clearly and sleep more deeply. We are more in the moment when gardening. Time passes unnoticed. We are in the zone, in a flow state, fully engaged in the right now, experiencing ourselves doing something positive instead of experiencing pain and loss.
And these claims are not just my opinion. Recent research has demonstrated that gardening has powerful therapeutic effects. Known in the psychology world as horticulture therapy, caring for plants reconnects us with ourselves, our communities, and nature. It is believed that planting seeds and caring for plants parallels our healing. There is even a professional association dedicated to this type of therapy. According to the American Horticultural Therapy Association, “horticultural therapy helps improve memory, cognitive abilities, task initiation, language skills, and socialization. In physical rehabilitation, horticultural therapy can help strengthen muscles and improve coordination, balance, and endurance. In vocational horticultural therapy settings, people learn to work independently, problem solve, and follow directions.” Horticultural therapy is frequently used in prisons, mental hospitals, rehabilitation facilities and retirement homes to improve healing and recovery.
Building a healing garden
You may have nothing more than a window sill or balcony, like me. You may have a huge yard. Odds are, you’re probably somewhere in between. Whatever your starting point, how can you create a space that will help you through difficult times?
First, any act of gardening will be a step in the right direction. Second, there is no Right Answer when designing a garden to help you heal emotionally. Whatever helps you is the best design.
My healing garden design
This post was inspired by a garden design that popped into my head while writing my gardening as therapy post. Let me share it with you, if I may. Imagine standing on the edge of a space in a rage, distraught and exhausted. Ready to lash out or give up, your feelings are mirrored by the plants closest to you: sharp thorns, ominous colors, looming trees, darkly shaded nooks and crannies. And a hard, rigid path.
A few steps down that path, things begin to change. It's a little brighter, the colors are somewhat softer, and you hear a gentle rustle. The path becomes less rigid, and it beckons.
The crunch of gravel under your feet is echoed by a gentle wind chime. A few shade-loving flowers brighten the way. A sweet aroma is carried on the breeze. A soft leaf brushes your hand, and you come around a bend.
The path is now soft and mossy. The view in front of you is a small woodland clearing with a patch of blue sky overhead. A bench invites you to set a spell. Birds flutter and splash in a nearby birdbath. Cascading flowers and fragrant herbs remind you that life isn’t always bad.
Don’t you feel better? I know I do.
I just learned about something you may be able to implement in your landscape called food foresting.
It ends up I was doing my own version of forest gardening when I lived in California. More on that in a minute.
Also known as forest gardening, this low-maintenance, highly sustainable method taps into the natural cycles of forest growth to produce fruit and nut trees, as well as edible herbs, perennial vegetables, shrubs, and vines. It is currently considered the most resilient agroecosystem, and you may be able to put it to work for you.
We all know that forests are critical to planetary and human health. According to the U.S. Department of Agriculture, “one large tree can provide a day’s supply of oxygen for up to four people.” They also provide renewable materials, cushion climate change, sequester carbon, and support biodiversity. They’re pretty nice to walk through, too. And forest gardening may solve problems associated with modern agriculture and provide bigger harvests from your landscape.
Food forest ecosystems
We all know that forests are dominated by trees. In the shade of those trees, other plants grow. Many of these plants are not edible, but they can be replaced with edible plants. There are different types of forests (boreal, temperate, tropical, and others), but we will skip that for now.
Trees provide shelter for birds and other critters. They also provide food for other plants, herbivores, and soil-dwelling organisms. When trees die, they fall. This mulches the ground below and creates openings in the canopy. Those openings allow young saplings to grow. The nutrient cycling and intercropping support of forest plants make them sustainable. Forest gardening taps into that cycle with perennial herbs, shrubs, trees, vegetables, and vines.
Did you know the majority of a forest’s biomass is underground, in the form of roots? I didn’t either.
The history of forest gardening
From the 1500s through the 1700s, Genoan landowners were required to plant four trees each year: olive, fig, mulberry, and chestnut. As a result, that area has rich, productive forests and farmland. [Imagine how productive your yard could be if you plant 4 food-producing trees each year!] But food forests go back much further than that.
I was surprised to learn that forest gardening has been around since ancient times. Prehistoric humans living in tropical regions used it to supplement the naturally occurring food they would glean from the jungle. They did this by protecting and nurturing favored plants growing close to their settlements while eliminating the undesirables. Some of those cultivated areas are still in use today. These mostly annual plantings are more similar to modern agriculture than one might expect.
In a far colder region, First Nation villages of Alaska have also used food forests to stabilize their food supply. They added non-native berries, herbs, and stone fruits to forest edges and next to existing trees in an early example of intercropping, or companion planting.
The indigenous people of the Pacific Northwest clear areas of forest to grow medicinal herbs, Pacific crabapple, rice roots, soapberry, wild cherry, and wild ginger. Unlike the annual growing cycles used by their jungle-bound cousins, these gardeners collected perennial plants and cared for them over many years. They used controlled burns, coppicing, fertilizing, and pruning to increase their harvests.
In the 1980s, Robert Hart used these principles and adapted them to temperate regions. Since forest floors do not get much direct sunlight, Mr. Hart focused on shade-tolerant plants. Since many of the plants used in forest gardens are perennial, forest gardening has close ties to permaculture.
Plants suited to food forests
Food forests have layers, just like other forests. Each layer is suitable for a specific type of edible plant. Look at the various layers of your yard. Does it already have a canopy? How and where can you add fruit and nut trees? Just be sure to keep their mature sizes in mind. Once you have trees in place (literally or on paper), consider the understory. There are a surprising number of herbs, shrubs, and vines that you can integrate into your backyard food forest.
Here is a list of the layers and examples of good plant choices for food forests:
Back to my California yard
When we bought a house in California, there was already apple, apricot, nectarine, and orange trees. Nothing else was particularly edible. By the time we moved 11 years later, my prim suburban backyard had been transformed with a shopping list of edible plants. Here’s a partial list: almond, artichoke, arugula, basil, beans, carrots, chives, cilantro, dill, eggplant, fennel, garlic, groundcherries, kale, lettuce…I could go on, but you get the idea.
Imagine my surprise when I learned that I now live only 10 minutes away from the U.S.’s largest food forest, Beacon Food Forest. Do you have a food forest near you?
Maybe I'll create a balcony plantation.
I am a baker, and I love the smell and taste of vanilla. I was trying a new recipe yesterday, a pear skillet tart, when I had a thought. Could I grow my own vanilla? Let’s find out.
The vanilla plant
Somewhere in the back of my brain, I had the idea that vanilla pods came from trees. I was wrong. Vanilla is a genus of orchids, of all things! Originally from Mexico and Belize, there are three major (and several minor) vanilla species: Madagascar vanilla (V. planifolia) is grown in tropical areas around the Indian Ocean; V. tahitensis comes to us from the South Pacific; V. pompona hails from the West Indies. Most of the vanilla extract we find in grocery stores is Madagascar vanilla, because of its stronger flavor. A few species grow in southern Florida, as well.
Vanilla orchids are vascular, evergreen vining plants. Those vines can be 35 feet long. They climb trees, called tutors. It is common to see aerial roots dangling from stem nodes. Underneath their gray outer covering, those aerial roots have green chlorophyll used to perform photosynthesis, as well as the thick, leathery leaves. Each flower produces one pod. Vanilla orchids generate a lot of flowers, but pollination can be a problem.
Like many other fruits, pollination is a necessary part of the process. Madagascar vanilla flowers have both male and female parts. This should make things easy, but it doesn’t. Those parts are separated by a membrane. The only bees that can pollinate vanilla flowers are Eulaema orchid bees, found throughout Central and parts of South America. These bees are only successful at pollinating vanilla flowers 1% of the time, which doesn’t make growing vanilla financially feasible. Because of this, all of the vanilla we buy comes from flowers that were pollinated by hand. Each flower. By hand. They use a bamboo stick to lift the membrane, and then use a finger to move the pollen from the anther to the stigma. That’s one bean.
This process was discovered by an enslaved 12-year-old child, Edmond Albus, in 1837. Hand-pollination allowed vanilla plants to be grown productively in other regions.
Did you know that 95% of the “vanilla” products you buy are flavored with vanillin and not vanilla? Vanillin is made from lignin. Lignin is a component of bark. It is also the stuff that holds trees upright. But it is not vanilla. And vanillin is only one of the 171 aromatics that make vanilla so delicious. In 1996, the FDA found that products labeled as vanilla were made from Mexican tonka beans, which are toxic. And that “natural flavoring” found on many food labels may not be vanilla or vanillin. It might be castoreum. Castoreum is something mature beavers use to mark their territory. Yuck!
When it comes to vanilla, paying for a quality product appears to be a good idea. The reason behind the high cost is that these crops are incredibly labor-intensive. If that weren’t reason enough, tropical storms and crop thefts are common in Madagascar. It’s a wonder we get any vanilla at all! But we’re not finished.
If you were able to get your hands on a vanilla cutting, you would need to provide a hot, humid, shady environment. Temperatures between 59°F and 89°F during the day, down to 68°F at night, are ideal, with 80% humidity. Living in Seattle, I wouldn’t have any problem with the humidity, but those temperatures might be hard to come by most of the year. If you live in a hot, sunny area, you would need to use netting that provides a shade rating of 50%.
Vanilla plants grow best in loose, loamy soil with a pH of around 5.4. Mulching around vanilla plants is said to help them grow well. Your vanilla cuttings will take three years to produce pods and should live 12 to 14 years.
Vanilla pests and diseases
Vanilla vines are prone to several fungal diseases, including Fusarium and Phytophthora. Mosaics, leaf curl, and other viral diseases can also occur. Many of these diseases are treated with Bordeaux mixture and other less environmentally or health-friendly solutions. Beetles, caterpillars, . grasshoppers, slugs, snakes, and weevils also damage vanilla crops. Sheesh!
So, can I grow my own vanilla?
I found vanilla cuttings on Etsy for $30, so, yes, they are available.
But, after learning about all that goes into growing, harvesting, and curing vanilla (and that’s all before we even start making the extract), I’ve decided that paying for high-quality vanilla is totally worth the expense. You may feel differently.
Like leaf rolling, leaf cupping is an easy-to-see warning that calls for closer inspection.
Cupped leaves tend to be thicker than healthy leaves. They may cup upwards or downwards. In some cases, they’ll do both. Sometimes, the conditions that cause cupping are temporary, and the leaves return to normal unaided. In other cases, the new shape is permanent, interfering with photosynthesis and creating safe havens for pests.
Leaf cupping may indicate diseases, insect feeding, or physiological factors.
Diseases that cause leaf cupping
When fungal diseases take hold, they often block the flow of water and nutrients through the vascular bundle. Armillaria root rot causes leaves to cup downward. Eutypa dieback also causes cupping.
Several viral diseases can also exhibit leaf cupping:
Leaf cupping and insects
Aphid and thrips feeding can result in leaf cupping. Regularly checking on the underside of leaves can help nip these problems in the proverbial bud.
Counter to popular myth, dish soap should never be used to eliminate pests. Dish soap damages plants. Horticultural oils and castile soap are better options.
Physiological causes of leaf cupping
Extreme weather, nutrient deficiencies and toxicities, and chemical overspray can cause leaf cupping. Chemical overspray occurs when herbicides are applied when a breeze is present (or a car drives by). The chemicals end up in places you don’t want them, causing phytotoxicity.
Plants may cup their leaves on hot, windy days, especially when water is in short supply. They may also respond to heavy pruning and digging in this way. I suppose it’s something of a panic response. Most of us tend to withdraw when attacked, so it’s no surprise that plants do something similar.
Deficiencies of boron, calcium, manganese, and molybdenum can result in cupping. Cupping may also indicate over-fertilization. Again, lab-based soil tests are invaluable. Luckily, they are inexpensive, too.
Plants may not speak in ways that we can hear, but we can certainly watch for things like leaf cupping as clues to what’s going on in the garden.
Mulberries of nursery rhyme fame are the fastest plants on Earth.
But before we delve into the particulars of this delicious tree fruit, I have to share what I learned while tracking down the nursery rhyme lyrics.
White mulberries are often banned because they cross-pollinate readily with red mulberry. But there’s more than that to mulberry pollen. Mulberry flowers release their pollen at approximately 380 miles per hour, which is more than half the speed of sound. This makes them the fastest plants on Earth. This pollen is responsible for many bans, but not because of the speed. Instead, it is a matter of quantity. The sheer volume of pollen released by male mulberry trees is enough to be hazardous for people with asthma or other respiratory problems. Female mulberry trees absorb that pollen but check with your local government to see if they are allowed before you start planting.
Mulberries are multiple fruits, like pineapples and figs, made up of drupes. They start green, yellow, or white. Most of them ripen to a deep purple or black. They do this because they contain anthocyanins. Anthocyanins are frequently touted as having antioxidant properties. They are what give plants their blue or purple color. While the antioxidant ability of anthocyanins does occur in test tubes, research has not yet been able to demonstrate that that ability carries over into real life. It ends up that we only retain about 5% of the metabolites responsible for antioxidant properties. That’s okay. Mulberry trees look nice, taste delicious, and they provide lots of vitamin C and iron.
Mulberry trees have both male and female flowers, called catkins. Black mulberries are monoecious, with both sexes on the same tree. This makes them self-fertile. Red mulberries can be monoecious or dioecious. Dioecious trees are male or female and are not self-fertile. I’m not sure about white mulberries. Just be sure to read the label if you are buying mulberry cuttings if you want fruit.
How to grow mulberries
Unlike most other fruit and nut trees, which are best grown from bare root stock, mulberries can be grown successfully from root cuttings or stratified seeds. Seed- and cutting-grown mulberry trees tend to be healthier and sturdier. I don’t know why. I do know that seeds should be stratified for 2 or 3 months at 34°F to 40°F.
They do require some patience, however. Like avocado trees, mulberries can take 10 to 15 years to produce fruit. While some specimens are said to live 125 years or more, the longevity of mulberry trees has come into question as several specimens are most short-lived.
Mulberry trees prefer slightly acidic, light, loamy soil. These are lowland trees commonly found along river banks, forest edges, and on sheltered slopes. They can tolerate drought and dappled shade but perform best when conditions are warm, moist, and sunny. Black mulberries can tolerate poor soil, but red mulberries need healthier soil to thrive. Mulberry roots are very brittle and need to be handled with care.
Mulberry tree care
In Britain, home growers often train grapevines up their mulberry trees. This is said to help prevent fungal diseases from occurring.
In commercial groves, mulberries are cut back to a height of 6 feet each fall (pollarding) and the removed branches are used to make baskets. In home gardens, mulberry trees should only be pruned when they are in full dormancy and only when completely necessary to remove dead or poorly placed branches. Mulberry trees bleed heavily when cut and some people are sensitive to the milky sap and unripe fruit of red mulberry trees, so you may want to wear gloves when working with them. (The trees, not the people). Unripe fruit may also give you a tummy ache, but young leaves can be cooked or eaten raw.
Many mulberry growers install a soft ground cover under their mulberry trees to cushion the fall of ripe fruit. You could also hang tarp hammocks to catch the fruit.
Mulberry trees are lovely and the fruit is delicious. Do you have room for a mulberry tree?
Pulling up a weed doesn’t always mean the end of that weed. One tiny piece of root left in the soil may be all that’s needed for a new weed to grow. That’s the downside of root cuttings. The good side is that you can use that behavior to propagate many desirable plants.
Just as scions can produce new fruit and nut trees, the roots of many herbaceous perennials and a few woody plants can generate free plants. Plants that have been grown from root cuttings rarely need any special care, and they tend to grow well. These baby plants have the advantage of starting underground, free of many aboveground pests and pathogens, such as aphids and leaf nematodes.
Root cutting candidates
Plants suited to this method generally have fleshy roots or runners. Here’s a partial list of edible plants that you can propagate from root cuttings:
How to take root cuttings
Take root cuttings when a plant is dormant when nearly all of its available nutrients and carbohydrates have been pulled into the root system. If a plant is large, you can dig soil away from the root system to select roots for cuttings. Otherwise, dig up the plant to be propagated and rinse off its root system. Select healthy roots that are the diameter of a pencil. Cut off those roots with freshly sharpened, sanitized pruners as close to the crown as possible. If you don’t have pruners, a knife is better than scissors to avoid crushing and damaging the root.
Take no more than one-third of a plant’s root system and replant the parent plant right away. As always, be sure to mud it in, rather than tamping down the soil. Once you have your roots in hand, follow these steps to get the best results:
*Cuttings compost is different from what you get from your compost pile. Since these roots already contain plenty of nutrients, what they need is a medium that drains especially well and is easy to move through. If the soil contains too many nutrients, the roots are less motivated to reach out and grow. Cutting compost usually has a high ratio of grit, sand, or vermiculite.
Many people cover their cuttings with plastic to retain moisture, but that can backfire in the form of fungal disease. I don’t use plastic. For me, it’s safer to monitor the soil and water lightly, as needed. Green shoots should appear in springtime. If nothing happens, take a closer look. You can pour the soil onto a cloth or sheet of newspaper to see what's going on. Sometimes root cuttings fail, and sometimes plants are slower than we'd like. Give them more time.
What about rooting hormones?
Rooting hormones, or auxins, are frequently used when taking stem cuttings in summer. Auxins encourage root development in those stems, but they are not necessary when working with root cuttings. Roots already know what to do.
Some plants are easier than others to propagate from root cuttings. Artichokes are, by far, the easiest I have ever found. This massive artichoke plant provided several daughter plants, and all I did was take a shovel, place it next to the crown, step on the shovel and chop off whatever was underground at that spot. I’d dig it up, rinse it off, remove any thin or damaged bits, dig a hole, plant it, and mud it in. That’s all it took. I had baby artichoke plants wherever I wanted them, for free.
Young woodchucks are known as chucklings, but you won’t be laughing if they find their way into your garden or lawn.
Woodchucks (Marmota monax) are also known as groundhogs, chucks, whistlepigs, and land beavers. These are large rodents related to a subgroup of ground squirrels known as marmots. Their name means digger. And dig they do.
Unlike other marmots, which prefer rocky, mountainous terrain, woodchucks are creatures of lowland soil and forest edges. Just as their distant cousin the beaver engineers and alters waterways, woodchucks are essential to maintaining healthy soil in the plains and woodland habitats. Native to Alaska, Canada, and the Eastern United States, there’s no telling how future populations may spread in response to our changing climate.
As a member of the squirrel family (Sciuridae), groundhogs tend to be grayish-brown, but with stubby tails. They have large incisors that grow (and are worn down) at a rate of about one-sixteenth of an inch each week. Adults can be two feet long, and their weight fluctuates seasonally, ranging from 6 to more than 11 pounds. They have short, powerful legs and long claws that help them burrow and climb trees. They can also swim.
Woodchucks are extremely intelligent, independent creatures that tend to be aggressive. They live in groups, called aggregations, and they whistle warnings and help each other burrow. After mating, a breeding pair will stay in the same underground chamber until the mother gives birth. Then the dad leaves until the young are weaned. Litters average three to five pups, though there can be as many as nine.
It’s unlikely you will ever see a groundhog because they hibernate in winter and spend much of the rest of the year underground or close to a burrow entrance. They are diurnal, which means they are most active at dawn and dusk. Captive woodchucks may live up to 14 years, while their wild siblings average only 2 or 3 years. A lucky few can survive up to six years, but badgers, bobcats, cougars, coyotes, dogs, gray wolves, and red foxes make short work of many adult groundhogs. Chucklings are often prey to cats, mink, raptors, and rattlesnakes. In some regions of the U.S., groundhogs are hunted for food, fur, and sport. [Why people consider hunting for sport humane in this day and age I’ll never understand.] Luckily for woodchucks, human development has provided a boon by reducing the number of predators while increasing their food supply. And therein lies the problem for gardeners.
The average woodchuck burrow has a six- to eight-inch opening and results in the removal of as much as six cubic feet of earth. This is good for the soil. No, it’s great for the soil. Woodchuck burrows aerate the soil, bring up subsoil and occasional artifacts, improve drainage, and aid in nutrient mixing without seriously damaging microbial networks. Their burrowing provides habitat for arthropods, increasing biodiversity. Those are all good things, but those burrows are big. And they can destroy a lawn or garden practically overnight.
Burrows can be more than 20 feet long, with small side rooms for sleeping, raising young, and pooping. Yes, groundhogs make and use bathrooms. In one study, a 24-foot burrow resulted in 640 pounds of soil being moved by two-foot rodents. Those tunnels can be three feet deep and have two to five entrances. These burrows can end up under your house, damaging its foundation. Of course, that would take a long time and several woodchucks, but it is possible.
Woodchucks are mostly herbivores. I say mostly because they will also eat baby birds, grasshoppers, grubs, and snails on rare occasions. They prefer wild grasses, berries, and crops (your garden). In their preparation for winter, these garden mammals can eat up to a pound of plant material each day. And they love apples, beans, broccoli, cabbage, carrots, corn, lettuces, melons, peas, and soybeans. Since they live in large groups, this can mean trouble for farmers and gardeners.
If groundhogs appear in your landscape each year, the first thing you can do is reduce the number of aboveground hiding places. This means piles of rocks, wood, or soil have to go. Many sources recommend fencing as a way to thwart groundhogs but, unless your fence goes three or more feet deep, they will still get in. You may need to cage your favorite plants. This is much easier with raised beds, but it does mean installing hardware cloth bottoms before adding soil and plants. Beyond that, there are lethal and nonlethal methods of controlling groundhogs.
Depending on where you live, you may choose to shoot them. Unless you are sure a lethal trap will kill instantly, I do not recommend that method. Fumigation is another option, but I am not sure about its effectiveness or humanity.
Since groundhogs are prey animals, installing scare tactics may work for a while. Like us, these creatures can get used to pretty much anything. Motion-sensing sprinklers, flashing lights, and noise-makers may chase away your local woodchucks for a while, but if they want what you’re growing, they’ll be back. And forget the ultrasonic repellers. They don’t work.
Live-trapping is an option, but only if you have the time, patience, and equipment. Or, you may want to invest in a professional for this task. They know what they’re doing and can relocate trapped groundhogs to a better location (far from your garden). Or learn to live with them if you can.
We couldn’t very well discuss groundhogs without mentioning the most famous one of all, Punxsutawney Phil. According to local tradition, a Pennsylvania resident groundhog predicts either six more weeks of winter or early spring every February 2nd, depending on whether or not he casts a shadow. This year, the prediction is for more winter.
Don’t worry, though. It ends up that groundhogs aren’t very good at predicting the weather. Since the tradition began in 1887, it’s only been accurate 39% of the time.
Now you know.
You can grow a surprising amount of food in your own yard. Ask me how!
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