How to Make a Lasagna Garden
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 the garden. Instead, it refers to the method of building the garden: adding layers of organic materials that will “cook down” over time, resulting in nutrient-rich soil that will help your plants thrive. Also known as sheet composting, lasagna gardening is beneficial for the environment because you're turning yard waste, kitchen scraps, and anything else you'd add to a normal compost pile into organic fertilizer to grow new plants.
Advantages of Lasagna Gardening
Although you maintain a lasagna garden the same way you would care for any other garden, you will likely find that lasagna gardening is less labor-intensive. You can expect the following:
- Fewer weeds, thanks to the newspaper or cardboard used in lasagna gardening suppressing them from below and the mulch covering the soil from above
- Better water retention, as compost holds water more effectively than regular garden soil (especially if your soil is sandy or deficient in organic matter)
- Less need for fertilizer, due to the nutrient-rich compost
- Healthy, loose, fertile soil that is easy to work
- Great for composting without a bin
What You'll Need
Equipment / Tools
- Garden hose
- Gardening gloves
- Organic materials, such as grass clippings, leaves, fruit and vegetable scraps, coffee grounds, tea leaves and bags, garden trimmings, shredded newspaper, cardboard, pine needles, aged animal manure (from herbivores), and peat moss
- Rope or twine
- Timbers or stones (optional)
- Garden plants of your choosing
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 form the outline of the garden bed. Consider creating raised sides for your garden using timbers, stones, or other hardscape materials to hold the organic layers in place as they decompose. There is no need to prepare the site beyond this because the layers of materials you'll be laying down will smother any existing grass or weeds.
Place the Layers
Alternate layers of "brown materials," such as shredded dry leaves, shredded newspaper, peat, and pine needles, with layers of “green materials,” such as vegetable scraps, garden trimmings, and grass clippings. The brown layers provide carbon to the garden, and the green layers provide nitrogen. Your "brown” layers should be roughly twice as deep as your “green” layers, though absolute precision is not that important. The result of your layering process should be a 2-foot-tall bed, which will shrink down in just a few weeks.
"Cook" the Garden
In most cases, you'll just watch as the garden materials begin to "cook" and break down. The rules for successful lasagna gardening are similar to any form of composting: The materials must be slightly moist to encourage decomposition but not so wet that they rot. In rare cases, such as during an extended drought, lightly water the organic layers to prevent them from drying out.
Plant the Garden
The time it takes for your garden to break down enough for planting will vary depending on the weather conditions. But once the materials have decomposed into a uniform layer of loose compost-like material, the garden is ready to plant. Simply 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 the 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 to the bed in the form of straw, grass clippings, bark mulch, or chopped leaves. Once it's established, care for a lasagna garden just as you would any other: Weed and water when necessary, and plant to your heart's content.
When to Make a Lasagna Garden
You can make a lasagna garden at any time of year. But fall is the optimum time for many gardeners because of the amount of organic materials available for mulching—fallen leaves, waste from garden cleanup, etc. You can let the lasagna garden sit and break down all winter. By spring, it should be ready to plant. Plus, fall rain 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, consider adding more soil-like amendments to the bed, such as peat or topsoil, so you can plant in the garden right away. If you start your lasagna garden bed in the spring, layer as many greens and browns as you can with layers of finished compost, peat, or topsoil interspersed in them. Finish the entire bed with 3 or 4 inches of finished compost or topsoil, and then go ahead and plant. The bed will settle over the season as the layers underneath decompose.
Tips for Making a Lasagna Garden
- Replenish your lasagna garden each year by adding more brown and green layers. Fall is a great time to do this because there are plenty of dead leaves and green plant materials at your disposal. Solicit lawn and garden waste from neighbors if you need more.
- To keep lighter materials such as dead leaves from blowing away, use a heavy material, such as wood chips, as the top "brown" layer of your garden bed.
- Avoid using certain materials in your compost, such as organic waste that has weed seeds in it. Unless the material "cooks" at a high enough temperature, these weeds will likely sprout in your garden.
- Do not add any plant material infested with pests or diseases, as these can spread in your new garden.
- Use only aged herbivore animal waste in your lasagna layers. Manure from carnivores can spread pathogens.
- Do not compost any meat, oil, or dairy in your lasagna garden or it can attract pests and wildlife.
What are the disadvantages of lasagna gardening?
There are pros (less labor yields weed-free nutrient-rich soil) and cons to lasagna gardening. The disadvantages include the following challenges: finding enough items to compost thick layers, keeping the bed moist for materials to compost, and the time it takes for the layers to break down for planting.
Can you plant immediately in a lasagna garden?
Yes and no. If you start your lasagna garden in the fall, it will be ready for planting by the spring. But if you want to plant immediately in your new lasagna garden bed, add an additional thick layer (4 to 6 inches) of peat, topsoil, and already decomposed compost. Source decomposed compost through your local extension office or your town may have a bulk composting source available for the community. It may also be available in small quantities at home improvement or nurseries.
Can you use wood chips in lasagna gardening?
Yes, you can use wood chips as part of your brown materials. However, do not use treated lumber or landscape mulch bought at the store. Wood chips for composting should come from the downed limbs and branches of trees and shrubs.
Lasagna Method. Hennepin County Master Gardeners.