Over at Cleantechnica, Sandy Dechert just posted about an encouraging study suggesting land use changes could halve the CO2 gap. And that's something we should all be paying close attention to.
From the dramatic regreening of Ethiopia to encouraging farming methods that sequester more carbon, there is a huge potential for large-scale land management changes to help curb the worst effects of global climate change.
Let's not forget, however, that small-scale changes can have a big cumulative impact too. Just as everyday efficiency improvements and distributed solar are contributing to falling fossil fuel demand on a national scale, changes in how we all garden (and how our parks and municipalities manage their land too) could help absorb carbon, promote biodiversity and provide a host of other benefits too.
So what should we be doing to help our gardens absorb more carbon? Ultimately, it's the same things that organic gardeners have been pushing for a long time. But here are the basics:
One of the primary differences between organic and conventional gardening and farming can be boiled down to a simple change in perspective: Instead of worrying about feeding the plants, we should worry first about feeding the soil—the plants will take care of themselves. By composting all of our food scraps and garden waste, we aren't just providing valuable nutrients for plants. More importantly, we are providing food (and habitat) for a huge ecosystem of bacteria, fungi and mini-beasts, all of whom help to absorb carbon from the environment and keep it locked up in the soil. Don't forget to add all your cardboard and other paper-based waste to your compost too—high fiber composting works, and it's another way to lock up some CO2 too.
Many old-school gardeners (like my mother) may scoff at the idea of no-dig gardening, but there are good reasons to abandon the rototiller. Just as no-till agriculture has gained a following for its ability to sequester carbon and maintain soil health, so too no-dig gardening could have a significant impact on preserving soil carbon. How much of an impact? The jury is still out, says the Rodale Instutute, as research into organic, no-till gardening is still in its early stages. But by slowing down the rate of decomposition in the soil, there is no doubt that you will increase soil carbon and save yourself some labor too. Not sure where to start? Check out this TreeHugger classic on how to start a no-dig garden.
Use cover crops
Part of the idea behind no-dig gardening is to avoid exposing soil microbes to excess oxygen and sunlight. Often this is done by mulching the crap out of your soils, but an even better way is to plant a living mulch of cover crops, or green manures, which can later be hoed down. Not only does it add carbon to the soil, but the root system helps keep soils in place and provides a habitat for soil life when your edible crops aren't growing.
Plant a food forest
You won't see acres and acres of monocultures in nature, so why do we plant farms and gardens with just one variety of one plant and expect our ecosystems to remain healthy? That's the thinking behind planting perennial polycultures like food forests, which are made up of a variety of different food plants which together mimic the functions of a natural ecosystem. True, it takes a bit of planning. And some "food forests" end up a little heavy on the comfrey, a little short on crops that you'd actually want to eat. But there are many examples out there of working food forests that are thriving, often combining annual vegetable gardening with fruit trees and other perennials.
Rethink your lawn
TreeHuggers tend to be pretty disparaging about conventional lawns. From the chemicals to the watering to the emissions-spewing mowers, there's very little to love about the cult of the perfect green lawn. Yet while the lawn care industry's claims that lawns are a carbon sink can be pretty easily debunked, we do have options for much greener (residential) pastures. Whether it's ditching the chemical fertilizers, planting drought resistant lawns, including clover in your planting mix or simply letting your lawn clippings fall where they are cut, we can feed the microbes in our lawns while reducing the need for water and fertilizers.
As demonstrated by an interesting article over at Sustainable Gardening, calculating exactly how much carbon your garden can sequester is probably an exercise in futility. But we can all make an effort to switch to climate-friendly gardening practices, and know that we are at least making a difference. Whether it's planting some trees, composting all of your waste or simply leaving the soil undisturbed, you'll be helping slow climate change, improve your local biodiversity and manage other environmental challenges like storm water runoff too. Plus, who really likes digging anyway? I always knew that being a lazivore was good for the planet.