Gardening is one of the most popular activities on the planet. Whether one lives in an apartment, in a single-family home, or on a farm, local food and flower production can be satisfying on multiple levels. A garden can be a source of nourishment, beauty, exercise, learning, and personal satisfaction. Gardening helps us to be sociable because almost everyone grows something or appreciates those who do.
Gardening is also a way of mitigating the effects of the climate crisis.
Reduce or eliminate synthetic fertilizers
A few years ago I began using composted chicken manure to supplement compost from my bins. The resulting vegetables were dramatically better. This is the kind of fertilizer my local food farmer friends use and it is acceptable for certified organic crop production.
We don’t ask a lot of questions about where the chicken manure originates, and maybe we should, but Iowa ranks first in the United States for egg production with 57.5 million laying hens according to the Iowa Poultry Association. With an 18.2:1 chicken to human ratio, chicken manure is an abundant resource.
There are plenty of reasons to be wary of synthetic fertilizers, according to the Climate Reality Project. Chemical runoff from haphazardly applied fertilizer can drain into streams and lakes, making its way to our water supplies. They can disrupt naturally occurring soil ecosystems, and are a temporary solution to a long-term solvable problem.
When it comes to the climate crisis, fertilizer manufacturing is the issue.
“Four to six tons of carbon are typically emitted into the atmosphere per ton of nitrogen manufactured,” according to Dr. David Wolfe, professor of plant and soil ecology in the School of Integrative Plant Science at Cornell University.
Gardeners should be more conservative about nitrogen use in the garden. Using composted chicken manure to improve soil nitrogen levels can produce great results and avoid the greenhouse gas emissions of synthetic fertilizers.
Plant Trees and other perennials
When we built our home in 1993 there were two volunteer trees on our lot, a mulberry which remains in the northeast corner, and another that died and was replaced with a blue spruce grown from a seven inch seedling. In all I planted 17 of 18 trees here, of which 15 remain. We also have three patches of mature lilac bushes.
The benefit of planting trees is they remove carbon dioxide from the atmosphere and store it. Because of their long life and size, they store more carbon than other plants. Scientific data shows the impact of trees on our atmosphere. The NOAA Earth System Research Laboratory at Mauna Loa, Hawaii measures carbon dioxide levels in the atmosphere. Last Saturday, the level of atmospheric CO2 rose to 415.25 parts per million, higher than it has been since humans evolved. Click on the chart of monthly CO2 levels and you can see the impact of deciduous trees. While the overall level continues to rise, as the world greens up in spring, CO2 levels predictably, consistently fall. When leaves fall from the trees, CO2 levels rise again. The thing about planting trees is do it once and the focus can turn to other things.
Trees offer cool shade in the summer and protection from winter winds, so a well-placed tree can reduce emissions and energy bills associated with heating and cooling a home. Fruit trees provide an added bonus for gardeners.
Reduce water use
Science explains that the warmer temperatures associated with the climate crisis increase the rate of water evaporation into the atmosphere, drying out some areas and then falling as excess precipitation in others. This can lead to a cycle of water misuse in ever-drier areas, and plant diseases in regions where average annual precipitation is on the rise. In Iowa we have seen all of that, with the record drought of 2012, and severe flooding that got within 100 yards of our home in 2008.
Lawn and garden watering is estimated to account for 30 percent of all residential water use in the U.S., according to the EPA, and that number “can be much higher in drier parts of the country and in more water-intensive landscapes.” And as much as 50 percent of it is lost to evaporation, wind, or runoff. Water conservation is everyone’s business. I’m not sure why anyone would water a lawn, except maybe a golf course. I don’t play golf. It is better to let a lawn survive in varying temperatures and moisture levels. Thus far in Iowa that’s been possible.
I don’t use an irrigation system or sprinkler in my garden. To ensure adequate moisture to sustain plants in seven plots, I use grass clippings as mulch. Often there are not enough clippings so I’ve been experimenting with plastic sheeting for peppers, cucumbers and broccoli. I have successfully re-used the plastic for multiple years. I use a garden hose to water at the base of the plants and do so sparingly.
“Less frequent, deep watering also encourages deeper root growth to areas where the soil stays moist longer,” according to the Cornell Cooperative Extension. “If supplemental water is determined to be necessary at a specific time and location, be sure to use no more than is needed and minimize your use of potable water.”
Focus on soil health
I have gardened non-stop since we moved into a rented duplex after our 1982 marriage. I have gotten better at gardening, but the biggest improvements came after we ceased being renters and bought our own homes, first in Lake County, Indiana, and then in Johnson County, Iowa. Owning our home enabled me to better consider soil health and long-term investing in it.
When we moved here the living layer of top soil had been removed and sold by the developer, leaving a hard, heavy surface devoid of earthworms and other visible life forms. Gardening, by its nature, must address soil health because if there is no life in the soil, fruit and vegetables won’t grow as well. This is the lesson of row crop agriculture where the best soil has eroded and what remains is supplemented with synthetic fertilizers and other inputs to create an artificial environment for plant growth and pest control.
The story of climate change’s impact on soil health is mostly about changing precipitation patterns, according to the Climate Reality Project.
Extreme downpours can lead to runoff and erosion, stripping healthy soil of key nutrients needed to sustain agriculture. On the other end of the spectrum, frequent droughts can kill off the vital living soil ecosystems necessary to grow healthy crops – and of course, plants can’t grow without water either.
What a gardener wants is soil rich in microorganisms that will sustain plant life through drought and heavy rains. After years of work composting and working our garden plots we can see plenty of earthworms. They are the most visible aspect of a rich miniature biome that sequesters carbon and stores water to make irrigation less needed. Healthy soil helps a garden survive short-term drought and heavy rains by sustaining moisture in the ground near plant roots.
Not many gardeners I know use cover crops, but that is an option to increase soil health. Like most, I add compost in the spring before tillage until the bins are empty.
Over the years my relationship with gasoline powered tillers has been inconsistent. A low- or no-till approach to gardening can plays a big role in building the soil organic matter. The reason is simple, when you rototill the ground, you break up the soil ecosystem.
“At its most basic, no-till gardening is the practice of growing produce without disturbing the soil through tillage or plowing,” according to the Climate Reality Project. “In addition to locking up more carbon in the soil, this approach dramatically cuts back on fossil-fuel use in gardening. After all, gasoline-powered garden tools are emitters of CO2.”
The best way to say it is I’m in transition regarding tillage. I have always turned over all the soil in a plot with a spade. What varied over time was whether or not I used a tiller. Sometimes a rented or borrowed a large rototiller to do everything at once, sometimes I used a smaller sized tiller inherited from our father-in-law’s estate, and now I break up the soil with a hoe and rake. I’ve been changing my way of thinking.
Last year I made a tomato plot but instead of turning the entire plot over and breaking the clods of soil down with a hoe and rake, I made two-foot lanes for the tomatoes. The production was excellent. Not tilling the entire plot leaves some of the soil structure in place and in the long term, that’s better for soil health.
This is an ongoing experiment, but the obvious conclusion is less tillage is better.
Opt for hand tools
My main garden tools are shovels, a hoe, rakes, a post driver, and a bucket of hand tools. Eliminating use of a rototiller was an important step in reducing emissions and using the spade, hoe and garden rake to break up the soil provides exercise. I also plant crops in four waves: early (kale, broccoli, peas, carrots, beets, radishes), succession planting (spinach, onions, leeks, herbs, beans and celery), tomatoes, and late (cucumbers, zucchini, squash, eggplant and peppers). Spreading planting over weeks helps make the physical labor of using hand tools more tolerable.
With a large garden and yard it proved difficult to make the battery-powered trimmer work: I kept running out of charge. When it broke, I got a new gasoline-powered trimmer. I also use my gasoline-powered mower and a chain saw. I used less than five gallons of gasoline between the lawn mower, chain saw and trimmer this year. Not perfect, but consistent with a practice to reduce the amount of garden emissions.
Part of my strategy of lawn maintenance is to avoid the use of chemicals completely and mow less often, maybe once every three or four weeks. The benefit of this practice is the lawn becomes a habitat for local flora and fauna. The downside is I don’t get enough grass clippings in a season for mulch. After years of the practice, the neighbors haven’t complained.
The climate crisis is real, it is now, and we have to do something about it. The lesson I learned from being a member of the Climate Reality Leadership Corps is there are many way to contribute to solutions in our daily lives. Among the things we do in a day, mitigating the effects of climate change must be one of them. We are all in this together and even a gardener can do something to help.
~ To learn more about the Climate Reality Project, visit climaterealityproject.org.