Lasagna gardening is a no-dig, no-till organic gardening method that results in rich, fluffy soil with very little work from the gardener. The name "lasagna gardening" has nothing to do with what you'll be growing in this garden. It refers to the method of building the garden, which is, essentially, adding layers of organic materials that will “cook down” over time, resulting in rich, fluffy soil that will help your plants thrive. Also known as “sheet composting,” lasagna gardening is great for the environment because you're using your yard and kitchen waste and essentially composting it in place to make a new garden.
No Digging Required
One of the best things about lasagna gardening is how easy it is. You don't have to remove existing sod and weeds. You don't have to double dig. In fact, you don't have to work the soil at all. The first layer of your lasagna garden consists of either brown corrugated cardboard or three layers of newspaper laid directly on top of the grass or weeds in the area you've selected for your garden. Wet this layer down to keep everything in place and start the decomposition process. The grass or weeds will break down fairly quickly because they will be smothered by the newspaper or cardboard, as well as by the materials you're going to layer on top of them. This layer also provides a dark, moist area to attract earthworms that will loosen up the soil as they tunnel through it.
Advantages to Lasagna Gardening
While you will be maintaining a lasagna garden the same way you would care for any other garden, you will find that caring for a lasagna garden is less work-intensive. You can expect:
- Few weeds, thanks to the newspaper suppressing them from below and the mulch covering the soil from above.
- Better water retention, because compost (which is what you made by layering all of those materials) holds water better than regular garden soil, especially if your native soil is sandy or deficient in organic matter.
- Less need for fertilizer, because you planted your garden in almost pure compost, which is very nutrient-rich.
- Soil that is easy to work: crumbly, loose, and fluffy.
Lasagna gardening is fun, easy, and allows you to make new gardens at a much faster rate than the old double-digging method. Now your only problem will be finding plants to fill all of those new gardens!
When to Build a Lasagna Garden
You can make a lasagna garden at any time of year. Fall is an optimum time for many gardeners because of the number of organic materials you can get for free thanks to fallen leaves and general yard waste from cleaning up the rest of the yard and garden. You can let the lasagna garden sit and break down all winter. By spring, it will be ready to plant in with a minimum of effort. Also, fall rains and winter snow will keep the materials in your lasagna garden moist, which will help them break down faster.
If you choose to make a lasagna garden in spring or summer, you will need to consider adding more "soil-like" amendments to the bed, such as peat or topsoil, so that you can plant in the garden right away. If you make the bed in spring, layer as many greens and browns as you can, with layers of finished compost, peat, or topsoil interspersed in them. Finish off the entire bed with three or four inches of finished compost or topsoil then go ahead and plant. The bed will settle some over the season as the layers underneath decompose.
- Working Time: The time required to prepare the garden is relatively short—generally just a few hours, depending on the size of your garden.
- Total Time: It will take a full season or two for the organic material to break down enough to support plants. You can, though, plant relatively quickly if you top off the bed with a layer of topsoil.
- Material Cost: A lasagna garden can be virtually free if you use your own organic wastes. At most, you might invest in a bale or two of peat moss. You can, of course, purchase compost and other materials if you don't have your own.
What You'll Need
Organic materials, such as:
Lay Out the Garden Boundaries
The first step is to define the boundaries of your garden. Rope, twine, or even a garden hose can be used to create the outline of your garden bed. There is really no need to prepare the site at all since any existing grass or weeds will be smothered by the layers of cardboard or newspaper and other materials you'll be laying down.
Because the layers will be stacked to a depth that is quite thick, you may want to create raised sides for your garden, using timbers, stones, or other hardscape materials to hold the organic materials in place as they decompose.
Place the Layers
Just as with an edible lasagna, there is some importance to the methods you use to build your lasagna garden. Alternate layers of “browns” such as fall leaves, shredded newspaper, peat, and pine needles, with layers of “greens” such as vegetable scraps, garden trimmings, and grass clippings. In general, your "brown” layers should be about twice as deep as your “green” layers, but there's no need to get finicky about this. Just layer browns and greens, and a lasagna garden will result. The end result of your layering process should be a two-foot tall layered bed. You'll be amazed at how much this will shrink down in a few short weeks.
A layer of cardboard or multiple layers of newspaper makes an excellent bottom layer since this will nicely smother grass and weeds within the garden bed. Water this bottom layer to hold it in place and encourage the decomposition process. After this, it is simply a matter of alternating green and brown layers until you reach a 2-foot depth.
"Cook" the Garden
In most cases, you'll need to do nothing but watch as the garden materials begin to "cook" and break down. The rules for successful lasagna gardening are much the same as for any form of composting: The materials need to be slightly moist to encourage decomposition and heat, but not so wet that the materials rot and become smelly. In rare cases, such as during extended periods of drought, lightly water the organic layers to ensure that they don't dry out entirely.
Plant the Garden
The time it takes for your garden to fully break down enough for planting will vary depending on conditions, but once the materials have decomposed into a uniform layer of loose compost-like material, the garden is ready to plant. When it's time to plant, just dig down into the bed as you would with any other garden. If you used newspaper as your bottom layer, the shovel will most likely go right through, exposing nice, loose soil underneath. If you used cardboard, you might have to cut a hole in it at each spot where you want to plant something.
Maintain the Garden
To maintain the garden, simply add mulch regularly to the top of the bed in the form of straw, grass clippings, bark mulch, or chopped leaves. Once it's established, you will care for a lasagna garden just as you would any other: Weed and water when necessary, and plant to your heart's content.
Anything you'd put in a compost pile, you can put into a lasagna garden. The materials you put into the garden will break down, providing nutrient-rich, crumbly soil in which to plant.
- Over time, the organic materials in the garden will break down and shrink. Replenish the garden each year by simply adding more brown and green layers. Fall is a great time to do this since there is a plentiful supply of dead leaves and green garden plant material at your disposal.
- Solicit organic wastes from neighbors. Offer to rake up their leaves and use them in your own garden beds.
- To keep lighter materials from blowing away, use a heavy material, such as wood chips, as the top "brown" layer of your garden bed.
- Avoid using organic waste that has a lot of weed seeds in it. Unless the material "cooks" at a high enough temperature, these weed seeds will likely sprout in your garden. And never use animal waste in your lasagna layers.