In the spring of 2019, Green America is teaming up with author and farmer Acadia Tucker to answer questions about Climate Victory Gardening. Join us here for bimonthly Q&A and submit your questions to ClimateVictoryGarden@GreenAmerica.org.
In the spring of 2019, Green America is teaming up with author and farmer Acadia Tucker to answer questions about Climate Victory Gardening. Join us here for bimonthly Q&A and submit your questions to ClimateVictoryGarden@GreenAmerica.org.
Don’t let a lack of space or an urban setting stop you from participating in the carbon capture movement. An excellent way to get your hands dirty is to sign up for a community garden. Or offer to help in someone else’s garden. I know lots of people who are doing both. If neither is an option, you can grow perennials in containers using regenerative techniques like composting, mulching, and minimal tilling. Here are a few tips to get you going.
Bigger is better when it comes to pots. Growing perennials in small pots makes it hard to take advantage of these plants’ robust root structures. Rootbound or crowded plants won’t weather outdoor temperature swings well and typically need more tending. A good rule of thumb is to choose a container that offers as much space below ground as a mature plant’s foliage above ground.
The biggest reason potted plants don’t fare well over time is soggy soil. Some containers come with drainage holes, but many do not. Buy the ones that do. If your pot is over six inches wide, it needs more than one hole.
Garden soil often becomes compacted over time. But unlike garden beds, which can be loosened with a broadfork, potted plants are almost impossible to aerate without damaging the roots. So make your own potting soil mix by combining equal parts peat moss or coconut fiber, good garden soil, compost, and sand. The peat moss and sand prevent soil from compacting and increase drainage. You can also just buy potting soil from your local garden store. Potting soil is usually mixed with perlite or vermiculite, textured styrofoam-like pebbles, to help container soil stay loose and porous. Look for potting soil that is 100 percent organic and, if you can find it, inoculated with mycorrhizae, a fungus that works with plant roots to absorb more nutrients.
While potted plants are resilient, they do take a little extra care. Garden plants have deep root structure that can find water and nutrients underground but potted plants depend on you to keep them moist and fed.
The exposed sides of the pot absorb heat and dry out the potting soil quickly. Water your soil whenever it’s dry.
Twice a year in the spring and fall, add valuable nutrients by layering on a half-inch of compost. I like to gently mix it into the first two inches of soil.
If your potted plants live outside in the summer, cover the top of the soil with mulch to keep it from baking in the sun. Mulch also helps retain moisture, whether your plants live inside or out.
If your potted plant has stopped growing, or the roots have pushed through the drainage holes, it’s time to repot. Find a new container big enough for your plant to stretch out and grow. Fill in the extra space with an equal mixture of potting soil and compost.
Yellowing leaves may mean a plant needs more nitrogen. I rely on liquid fish emulsion to quickly boost plant growth. It’s simple to add, since you don’t need to mix it into the soil. Dilute the concentrate with water, following the instructions on the label, and slowly pour the mixture into the pot. Be aware that fish emulsion smells pretty, well, fishy, which can be a problem for indoor plants. Cut down on the stink by adding a few drops of lavender oil before pouring.
When I first started growing food, the farm I managed in the Pacific Northwest had patches of sandy, dry soil interspersed with waterlogged, hard packed clay. During the scorching hot summers, my thirsty plants shriveled. When the skies dumped rain the water pooled, flooding my crops. Those first couple of years on the farm were my first experience dealing with climate extremes, and my soil was not equipped for the job.
Worried about the outlook for my farm, I returned to school to study soil and water management, and did a deep dive into how global warming is changing the way we raise food. The experience helped turn me into a very different kind of grower.
When I returned I started covering my beds every spring with a generous layer of compost. On top of that, I laid down another protective layer of straw or grass clippings mixed with shredded leaves, to keep the compost from washing away and prevent new weeds from sprouting. Over the course of the growing season I dosed my soil with this potent combination as needed. It didn’t take time to notice a difference.
In just over a year, the rich organic material had converted the light brown, sandy soil into a dark brown, fluffy bed for my plants. The hard packed clay loosened and become more friable. Water sank instead of sitting on the surface. I swear my food is tastier and more resilient. But what really excites me about my job as a soil farmer is knowing the role it plays in cooling our environment.
The more organic matter in the soil, the more excess carbon dioxide it can absorb. Increasing the carbon stored in soil helps to maximize photosynthesis so plants can draw down even more carbon dioxide and trap it underground.
Moreover, soil rich in carbon feeds mycorrhizae, a vast network of fungi that releases glomalin. Glomalin is a sticky, gum-like substance that binds together particles of sand, silt, and clay, creating a soil structure that conserves moisture and holds onto nutrients. Plants raised in favorable conditions like this, with easy access to moisture and nutrients, grow sturdier and more resilient. This positive cycle is how nature works when we don’t interfere.
By adopting soil-building, regenerative practices, farms could remove carbon dioxide from the atmosphere at a rate of about one ton of carbon dioxide for every acre, according to data reviewed by soil expert Eric Toensmeier. The potential benefits are enormous, as spelled out in a 2014 study from Rodale Institute. Citing data from farming systems and pasture trials, it concludes that we could sequester more than 100 percent of annual CO2 emissions worldwide if we start growing food this way.
But even if you have nothing more than a sliver of land you can do something right now to battle the most significant ecological threat we’ve ever faced. Carbon farming expert Eric Toensmeier estimates that his own tiny carbon-rich backyard garden, about a tenth of an acre, can offset the carbon emissions of one American adult per year. So let’s all start nurturing the soil. It’s time.
The occasional soil test is a helpful gauge of what’s working and whether you need to pile on more compost or other amendments, so I’ve built soil testing into my annual routine and recommend you do, too. If you’re starting a garden from scratch, taking measure of your soil’s acidity and nutrient levels can get you off to the right start. Most state universities can test for acidity, organic matter, and nutrients. That said, testing the quality of your soil isn’t absolutely necessary for regenerative gardeners if you treat it with a healthy dose of compost and mulch every year. And if getting a test seems like a hassle, and stands in the way of you getting started on your own garden, don’t bother. Better to just get started.
You can easily keep tabs on the health of your soil each season by grabbing a handful of moist dirt from your garden and squeezing it. If it crumbles, your soil is too dry and sandy and you’ll have to add more organic matter. If it holds its shape even after some poking, the soil contains too much clay and you’ll have to mix in peat, compost, or lime to break it up and improve drainage. If your clod holds its shape and falls apart only after poking it, then your probably have rich, well-drained loam soil, which most plants love.
Adding organic matter is the most important step you can take to build healthy soil. Organic matter is anything living or dead, animals or plants, and the perfect food for soil organisms. So, I feed my soil with compost.
Throughout the season I build up my compost pile with straw, grass clippings, leaves, kitchen scraps, plants, pretty much any raw organic material, and let it sit. This creates a breeding ground for bacteria and microbes that make quick work of breaking down the materials into nutrients that plants need. The result is black gold packed with organic matter and plenty of the trace minerals - like iron, zinc, and manganese - that are left out of synthetic fertilizers.
Each spring I spread one to two inches of this amazing stuff over the entire garden, gently mixing it into the first few inches of the soil. But if you forget to feed your soil during the busy spring it’s fine to add it later on, and particularly poor patches of land benefit from getting it throughout the season.
Mulch is a carbon farmer’s best friend. Spreading mulch over the soil each year accomplishes many goals at once. For starters, mulch helps trap water so you won’t need to water your plants as much. Mulch also fights against weeds so you spend less time hunched over pulling them out of the ground (you can tell how much I like weeding) and more time enjoying the fruits of your labor. But the most important aspect of mulch is the way protects the soil.
I add it in the spring, to prevent the healthy soil I’ve worked so hard to build from washing away. And in the fall, to keep nutrients in the ground and protect plant roots from becoming exposed and vulnerable to drying out and freezing in the winter.
Mulch works best when applied in an even layer, two to four inches deep. Make sure to keep it a few inches from the base of your plants so it doesn’t rot them. I spread wood chips along my pathways to prevent hard-packed soil, and a layer of shredded leaves and grass clipping or straw on my plant beds. But you can use pretty much anything from plain cardboard or newspaper to coco fiber or shredded tree waste from your local municipality. I much prefer organic materials, which can be broken down by soil microbes, rather than synthetic mulches like landscape fabric, which does nothing for soil health. The best organic mulches are readily available, cheap, and easy to spread.
When I lived as a market farmer in Washington State, Saturday afternoons were a celebration of sorts. After a busy week of tending and harvesting up to 200 different herbs and vegetables, I’d invite the community to a weekly farmstand. I’d begin preparations early and by 11am the vegetable display was primed with puffed bags of lettuce and tall, carefully stacked pyramids of freshly picked tomatoes. It was a relief to open the farm gates and finally be able to sit and chat with friends and neighbors.
Locals would gather in the shade of the cedar farmstand, cradling cucumbers and onions, and ask their most pressing gardening questions. The most common one, by far, was, “how can I grow food like this at home?”
“It’s easy!” I’d reply, and groans almost always followed. They told me stories about ripping out huge sections of lawn only to give up because planting vegetables was too much work. Or about the uncontrollable problems caused by piling fresh soil onto a bed without first pulling out all the weeds. They complained about soil too poor to support the growth of healthy plants.
I had to admit that what seems easy to me, someone entirely oriented around growing food, is of course much harder if you’re more accustomed to growing grass. So over time I learned to break down my “It’s easy!” into small steps that can lead to a starter Climate Victory Garden.
So here’s my advice: pick a good spot to plant, start small, and focus on nourishing healthy soil. It takes work but, honestly, it is easier than you think.
An ideal planting bed gets plenty of sun, has easy access to a water spigot, which helps cut down on the time and hassle of watering, and can be seen from your home so there’s less of a chance you’ll forget about it. But if your only bet is a plot that’s heavily shaded and bone dry, don’t worry about it. It just means you’ll have to work extra hard to build good soil, and pick plants that will thrive without much sun. In short, it can be done!
Start small to keep the workload under control. If you end up wanting more space you can always add onto it later. While garden beds can be any size you want, you will want to consider the width. Namely, can you easily reach across it to tend plants?
Stepping on beds will compact, or squeeze together, soil particles. Without air pockets, it’s harder for soil to absorb water and store nutrients. Compacted soil also crowds out all those good organisms that break down debris, ward off soil-borne pests, and tunnel through the soil so that plant roots can stretch out.
Some gardeners like to head to the hardware store to buy wood, build a box, and fill it with soil. I’d rather skip the work and expense of that approach, and just build a bed on top of the ground using one of the following three techniques.
1. Sheet mulch your plot.
You’ll need cardboard or newspaper, leaves, grass clippings, compost, and any other organic material you can get your hands on. First, lay moistened cardboard or newspaper over your lawn or dirt. If you plan on planting large woody perennials like fruit bushes, cut a hole in the cardboard and plant your bushes through the hole. Then layer on grass, leaves, and compost in thick layers, about two inches each, and repeat until the materials run out. For best results, you’ll want to do this at least twice.
The thick mat of material not only smothers weeds, it buries seeds so future weeds are less of a problem. You may be surprised at first by the height of your bed. Give it time. Busy soil organisms will quickly shrink the pile of organic material. For now, finish off your heap with some fresh topsoil or well-aged compost if you want to plant right away. Or just let it sit and allow nature to take its course. Over time all those grass clippings and shredded leaves will decompose and morph into soil. Once it does, weed out any fresh green sprouts, and start planting.
2. Minimal to no tillage.
Breaking down soil with a rototiller is a truly effective way to tear out lawn and weeds, and it used to be one of my favorite farming activities. But then I learned it’s also an efficient way to destroy good soil structure, exposing stable soil carbon and releasing it back into the atmosphere as carbon dioxide. So I’ve given up tilling, mostly. To create a new bed, I now use a spade, hoe, and potato fork to dig up clumps of sod until the ground is bare rather than a rototiller. This can take a lot of work. The good news is you’ll only have to do it once.
After clearing out the grass and weeds, you’ll need to loosen and aerate the soil. This lets air and water enter the soil more easily so soil organisms have plenty of pockets of space to call home. Take a shovel and dig a trench along the edge of your new bed, dumping the soil in a wheelbarrow if you have one. Fill the trench by digging a new one right next to the first. As you dig the second trench, toss the soil into the first one. Repeat this process until the entire bed has been trenched and filled. After digging your final trench, fill it with the soil you set aside in the wheelbarrow. Now that all the soil has been loosened, level the bed with a rake, and it’s ready to go.
3. Just add soil.
There’s another way to prepare your planting bed: add more soil. But it’s not quite that easy. First, you’ll have to clear off the grass and weeds, as described above. Then shovel on soil from anywhere in your yard. If you don’t have much soil -- maybe your yard is too weedy, hard to dig up, or just not all that big -- buy a few bags of it from your local garden center. Make sure any soil you buy is dark brown and clear of debris. Add enough of it so your bed is three to eight inches high. Any higher and you run the risk of having soil wash away during big storms or intense rainfall, plus, it may dry out more quickly.
Once you’ve eliminated any weeds and grass and built your bed, it’s time to jump-start the growing process by working compost into the top three inches of your soil. Compost is decomposed organic material that can work miracles in a garden. One small handful teems with millions of beneficial soil dwellers, from the tiniest decomposer microbes to nutrient-recycling nematodes and, larger still, soil-moving earthworms. All of these eat carbon for energy and, in the process, break down organic matter into plant-available nutrients that help you grow tasty crops. In addition, these creatures give your soil a porous, open structure so water can penetrate, instead of running off.
Note: You won’t have to add more compost during the planting process if you’ve opted to use sheet mulching or good soil from a gardening store. But you’ll still want to refresh your beds with compost each spring after your garden is established.
Pest populations can explode even if you keep your soil healthy and maintain a balanced garden ecosystem. Pest management is a natural part of growing plants and occasionally gardeners need to rely on external control measures like spraying pesticides. Organic gardeners shy away from using pesticides for some very good reasons. Sprays, particularly if they are not organic, can kill beneficial bugs and insects, like the bees that pollinate your raspberries or the insects that cycle nutrients through your soil. Pesticides also find their way into the food chain because plants absorb chemicals through roots and leaves. Fortunately you can mitigate the risk of using pesticides by relying on ones certified for organic use, which tend to be derived from plants or bacteria.
Note: Certified organic or not, you want to keep pesticides in their original containers, out of reach of pets and children and in a dark and dry place that never drops below 40 degrees or gets hotter than 100 degrees. I keep mine in a dark closet in the house and avoid leaving it in the garden shed.
NEEM OIL: Using Neem oil is a great preventive control measure. It comes from the bark and leaves of the Neem tree, a common evergreen grown in tropical and subtropical regions. Azadirachtin, the active ingredient in Neem oil, makes insects grow slowly and eat less. It also makes them lose interest in laying eggs so there are fewer of them to begin with. Neem is particularly effective against fast growing beetles, small caterpillars, and aphids.
Use Neem on plants as soon as you see the first adult bug, and spray weekly. Keep your bees safe by covering treated plants with a row cover. Don’t expect Neem to instantly rid your garden of pests. It works over time by limiting the reproduction and growth of bad bugs. If you want to speed up the process, you can also hand-pluck adult bugs from plants.
How to prepare it: Most Neem products come as a concentrate that needs to be mixed with warm water before spraying it onto your plants. Follow the label instructions to know the proportions to use. Apply the mixture weekly to the tops and underside of leaves. Avoid spraying in direct sun, since it will burn oil-covered leaves, much in the way baby oil causes skin to burn.
Store: Concentrated Neem can be kept for up to two years.
INSECTICIDAL SOAP: Insecticidal soaps are an effective way to control soft-bodied insects if no beneficial bugs are around to do the job for you. The fatty acids in insecticidal soaps break down the protective cuticles of soft-bodied pests like aphids and caterpillars, which become dehydrated and die.
Soap sprays only kill insects that are sprayed directly so be sure to thoroughly wet both sides of leaves and avoid spraying beneficial insects, like bees and spiders. Repeat applications every five to seven days, as new pests hatch and form colonies. I keep a few premixed spray bottles on hand so I can spray pests as soon as I see them.
How to prepare it: Make your own soap spray by mixing one tablespoon of dishwashing soap per quart of water. You can also buy an insecticidal soap concentrate. Follow label directions for diluting it because using too much can harm plant leaves. If you have hard water at home, use bottled water to make sprays, because the minerals in hard water reduce the effectiveness of insecticidal soap.
Mix only as much concentrate as you need for the day and keep spray bottles out of the sun, which will degrade the quality of your spray and make it less effective. Any unused sprays that haven't been used in a week can be diluted with more water and poured out in the garden far from any storm drains.
Store: Soap concentrates can last for up to five years.
DIATOMACEOUS EARTH (DE): DE is made from the pulverized fossils of tiny sea creatures and looks like broken glass if you peer at it under a microscope. It kills insects by slicing up their protective outer layer and causes fatal dehydration when they walk through the dusty white powder. You can dust the leaves of your plants to kill leaf-eating bugs or create a barrier of white powder at the base of your plants to stop slugs.
DE is great for killing slugs, newly hatched Japanese beetles, and wireworms. It works best in dry conditions because rain makes the powder congeal in clumps and lose some of its sharp edges. If it rains, reapply once your plants have dried.
Store: Make sure to store your DE in an airtight container to keep it dry. Properly stored DE can last indefinitely.
BACILLUS THURINGIENSIS (Bt): Bacillus thuringiensis, or Bt, is a naturally-occurring bacteria that ruptures the internal organs of leaf-eating insects like caterpillars. It only works on the bugs that eat treated leaves. It has no impact on pests that are directly sprayed so bees and other pollinators are left alone.
Direct sunlight degrades Bt after a few hours, so apply Bt late in the day when the sun is low. It will work to kill pests during their nightly feeding. You can use Bt every 10 days to control caterpillars and other leaf-eating insects until they're no longer a problem.
Store: Powdered Bt products can last for five years, while liquid Bt products last only about two years.
SPINOSAD: Spinosad is another naturally occurring bacteria, Saccharopolyspora spinosa, which produces a deadly neurotoxin that makes infected insects excited to the point of utter exhaustion. After eating it, insects immediately stop feeding and die within a few days. Spinosad works to control all types of caterpillars and some beetles that eat a lot of leaf tissue.
Apply spinosad to dry leaves as soon as you notice leaf-eating pests in the garden. Thoroughly wet both sides of leaves. Much like Bt, spinosad breaks down in direct sun, so late afternoon applications are the most effective.
Spinosad is somewhat absorbed by plant leaves so one treatment can last up to 10 days. Within the first 24 hours of spraying be careful not to let treated leaves come in contact with beneficial insects, like bees. You can protect your good bugs by draping treated plants in row covers, or fabric, for a day.
Store: Spinosad products last about three years.
PLANTSKYDD: I know people who swear by this. Plantskydd is environmentally safe and works against rabbits, voles, moose, chipmunks, squirrels, nutria, beaver, groundhogs, and deer. It can last up to six months - even over the winter season. It repels, according to company literature, by "emitting an odor that browsing animals associate with predator activity, stimulating a fear-based response that will have garden feeders looking for somewhere else to dine."
Originally published on Stone Pier Press.
Acadia Tucker is a regenerative farmer, climate activist, and author of Growing Perennial Foods: A field guide to raising resilient herbs, fruits & vegetables, and Growing Good Food: A citizen's guide to backyard carbon farming. Her books are a call to action for citizen gardeners everywhere, and lay the groundwork for planting an organic, regenerative garden. For her, this is gardening as if our future depends on it.
To learn more about Acadia and read an excerpt from her book, check out this blog!
Have a question you'd like to ask Acadia? Send it to: ClimateVictoryGarden@GreenAmerica.org.
Or, post it on the Climate Victory Garden Facebook group.