Cooking up a New Bed with Lasagna Gardening
By Brenda Ortmann, Anoka County Extension Master Gardener
Do you want to create a garden, but dislike the idea of prepping one? Few people enjoy pulling up sod or tilling soil, but these are the methods familiar to most gardeners. Luckily, there is another option that will spare your back if you're willing to give nature some time to work. It's called lasagna gardening.
Similar to building a lasagna, the trick to this technique is to layer organic material that will break down into rich, fertile soil during the growing season. Lasagna gardening works both on the ground or in a structured bed.
To assemble a lasagna garden, begin by layering newspapers or putting down a single layer of non-coated cardboard on the designated space. This first layer forms a barrier between the existing soil and the compost layers that will follow. It suppresses grass and weeds from below and keeps the nutritious layers of compost on top. Without this barrier, the compost will gradually sink into the sandy soil that most of us live with in Anoka County. This layer helps retain moisture, reducing the need for frequent watering. Once your first layer is in place, water it down before proceeding.
For the second layer, add at least six inches of brown organic material. Brown materials can include small branches, old mulch, straw, leaves, shredded newspaper, torn-up cardboard, and sawdust. Branches, sticks, and mulch allow for good aeration and help with decomposition. This layer also gives structure, absorbs moisture, and provides carbon for the garden.
The third layer should consist of a few inches of green organic materials. Green organics can include pesticide-free grass clippings, compostable kitchen scraps, composted manure, and coffee grounds. This layer provides moisture, nitrogen, and other nutrients.
Repeat the three layers until you get your desired depth. Keep in mind that the pile will gradually shrink as it breaks down. Brown and green layers do not need to be pre-composted; this will happen naturally over time as the garden becomes established. Brown to green layers should be added at a ratio of 2:1 or 3:1.
If you want to plant your garden right away, add a top layer of quality garden soil at least three inches thick. Good options include a mixture of compost, topsoil, and either coconut coir, vermiculite, or perlite.
Feel free to be a creative ‘cook’ and use what you have. Since we have moles and voles in our yard, our first layer started with protective garden mesh, followed by cardboard and then sticks. Our layers included old mulch, straw, and the contents of our compost bin. After planting, we top-dressed the fourth layer with straw to control weeds and hold in moisture.
Once your lasagna garden is established, the only maintenance is to plant and mulch each year. This process was so simple that we plan to add two more beds this spring. Whether you are looking to create your first garden or add an additional plot, you can put away the sod cutter and cook up a lasagna garden!
Join us for "Ask a Master Gardener Online" every Tuesday, 6:30 - 7:30 p.m., May - August. Visit anokamastergardeners.org to register and learn more about our free classes, events and projects.
