The key to a successful Climate Victory Garden is preparing your soil. This is where crops gather nutrients to grow your food and where carbon is sequestered as part of the climate solution. Whether you’re updating a current garden, replacing your lawn, or just covering a weedy area, your garden soil needs to be prepared and enhanced for planting.
Don’t let anyone tell you that you need to buy expensive bags of soil from the store. The easiest and most inexpensive methods for preparing the ground are to broadfork and sheet-mulch your garden area.
Note: these processes are best done in the fall, but it can take an entire season to gather supplies, so do your research and plan ahead!
Using a broadfork
The broadfork, also called a U-fork or grelinette, is a tool for manually breaking up densely-packed garden soil like hardpan to improve aeration and drainage. An important part of Climate Victory Gardening is protecting soils and limiting the amount you disturb them. This allows the microorganisms in the garden soil to better hold onto carbon. But, some soils need to be loosened up to create space for roots and more abundant life that make for a healthy garden. A broadfork helps you do this with the least possible disturbance.
Before using the broadfork, consider testing your soil to see what it may be lacking, and add nutrients as recommended while loosening the soil.
To use a broadfork, plunge the tines into the earth, jump on the horizontal bar, and rock back and forth to loosen the soil. Then move forward a couple feet to repeat the process until all the garden soil is aerated. This is preferable to tilling and completely turning the earth over because it’s less disruptive to life in the soil.
That said, this is a substantial tool and one you likely won’t need often. Your best bet is to find one at a local tool share program or contact local garden groups to see if you can borrow one.
Once you’ve aerated the entire area, you're ready to plant. Or, build up your soil health even more with sheet-mulching or lasagna gardening methods.
Sheet-mulching and lasagna gardening
Lasagna gardening, also known as sheet-mulching, is best for when your garden soil isn’t terribly hard or compacted (if it is, consider using a broadfork first). It’s a free way to build rich, healthy soils and is a good option if you have an abundance of weeds or are unable to physically turn your soil with a broadfork.
This method gets its name from the delicious layers or sheets of organic matter that you’re creating to feed the organisms in your garden soil. As these layers decompose, they feed soil life and make nutrients more accessible for the plant you grow.
These layers can be applied directly on top of grass or weeds (except particularly resistant and invasive weeds like crabgrass, which need to be removed by hand). Cover the area with cardboard and/or 3 to 5 layers of newspaper and wet it down to keep it from blowing away. The next layer can be any organic material that you would use in a compost pile. Alternate layers of green materials, like grass clippings and raw vegetable peels, with brown materials like dried leaves, straw, or shredded newspaper. Think of green layers as more wet ingredients and browns as drier. Continue to alternate the green and brown layers until your garden bed is 18 to 24 inches high. Finish with a layer of mulch and thoroughly water the area.
Timing and gathering materials
If you want to plant immediately after layering your lasagna garden, consider using more soil-like ingredients in your layers than paper and cardboard. Otherwise, it’s best to plant when the layers have started to decompose or to cut out areas to plant. Because of that, these garden soil preparations might be best done at the end of a growing season. Preparing your land in the fall gives these materials a chance to age and decay into garden soil over the winter.
That said, it could take an entire season to collect enough materials for lasagna gardening, so start gathering today! You can save newspapers and cardboard, but avoid glossy paper, tape, and staples. If you don’t have these materials at home, recycling bins can be good sources. Toss food and yard wastes in your compost pile (or keep in the freezer), noting that you can use these materials to layer even if they’re not fully decomposed. In the fall, collect dry leaves.
Pro tip: No time to collect this diverse list of materials? Use the late summer and fall to build a circular 16-gauge wire fence enclosure and alternate 6-10 inches of shredded leaves with a thin layer of soil or spent coffee grounds to promote decomposition. Water each layer and repeat until full. This makes for a great source of material for future plantings.
Both using a broadfork and sheet-mulching techniques helps soil retain carbon by adding organic material, making these methods powerful tools in the climate solution. If you’re using the Climate Victory Gardening practices that support soil health, you shouldn’t have to disturb your garden soil or repeat this process again. At the end of future growing seasons, remove dead or dying garden plants, spread compost or wood chips, and consider adding cover crops to increase fertility.
Written by Tom Van Dyke, a Master Gardener in the eastern panhandle of West Virginia, whose mission is to grow food sustainably. He has advanced degrees in food systems management and taught about food issues at the university level before retiring in 2013. (Top Photo Credit: mwms1916)