Editor’s Note:Today’s guest post is from Susan at Learning & Yearning. Susan Vinskofski planted her first flower at age 8, dug up her parents entire, small backyard at age 16 to plant a vegetable garden, and has been gardening ever since. Now a Master Gardener in her Pennsylvania county, Susan is passionate about building soil and growing and eating the most nutrient-dense food she can find.
I wouldn’t know how to begin a discussion on gardening without beginning with the soil. When I teach a workshop, I ask people what they think of when they think “garden”. Most often, the answer has to do with the harvest. And, of course, we wouldn’t garden if we couldn’t look forward to a bountiful harvest. But, I always encourage my students to think “soil” because healthy soil will result in a healthy, nutrient-dense harvest. A garden with poor soil may produce fruit, but that fruit can’t possibly contain the nutrients, or taste as good, as one grown in soil that has provided all that is needed for its health. And plants grown in healthy soil have less problems with disease and pests.
Components of Healthy Soil
So, what makes soil healthy? Soil is so much more than dirt. One of the components is, of course, weathered rock. That is where our garden plants will receive many of the minerals that they need. Good soil also contains organic matter – things like worm castings, decomposed leaves, and even the remains of soil organisms like insects, fungi and bacteria. Replenishing organic matter is essential to soil care.
Soil also needs air and water. Soil without air spaces is compacted and neither roots nor soil organisms will have the space they need to grow and breath. Earthworms, as they build tunnels, help to aerate the soil. And we can help by never stepping on the area where plants grow, but rather maintaining paths or building raised beds. And of course, plants would not survive without the water in soil which is used in the process of photosynthesis and for transporting nutrients through the roots and up into the plant.
Finally, the texture of soil – the size of its particles – has a direct effect on how well your garden will grow. Sand, of course, is composed of large particles, and water will pass through it quickly. Clay, on the other hand, is made of extremely small particles. Clay is sticky when wet and has few air spaces and drains poorly. What I want to do is to teach you to build a garden in a way that the original soil that you have to work with won’t be what determines your end result.
Building Healthy Soil
If there was only one piece of advice I could give to improve your soil, it would be to compost. This dark, crumbly, “black gold”, is made up of decomposing organic matter which builds your soil and keeps kitchen scraps and yard debris out of landfills. One method of composting – sheet composting – is simply composting in layers on top of either an existing garden or on top of turf with the purpose of building a new garden or improving an existing one. This is really easy and will revolutionize gardening for you. This method of gardening, also called ‘lasagna gardening‘ involves no digging and very little weeding – the two chores that tend to discourage people from gardening. Setting up a garden this way does require work, but it’s so much easier than tilling a garden. And once your garden is prepared, yearly maintenance is simple.
A lasagna garden is built by layering organic materials which eventually will decompose into wonderful garden soil. While it is preferable to build the garden several months in advance, it is not totally necessary to wait until that decomposition is completed to begin planting in the layers. Here are general guidelines for building a lasagna garden, but the great thing is that there is no exact right way to do this. You may use whatever materials you have available.
A lasagna garden is built right on top of the ground; there is no need to dig first. If you’re building on top of grass, this will decompose, too, and add nutrients to your garden. The first thing you’ll do is lay down cardboard or a 1/4” – 1/2” layer of newspaper right on the ground to choke out grass and weeds. Don’t use any colored, glossy newspaper. Thoroughly wet this layer to help speed the decomposition. From here, you will layer whatever types of organic matter that you are able to get your hands on. Some of the types of items that you could use would include:
- partially decomposed tree limbs – best used as a bottom layer in your garden.
- leaves – preferably chopped. Use in thin layers if not chopped.
- manure – if you plan to plant your garden soon, only use well rotted manure. Fresh manure will burn the roots of the plants.
- weed-free hay or straw
- coffee grounds – some coffee shops give these away; just ask.
- grass clippings
- shredded newspaper – nothing colored or glossy.
- wood chips
After laying down your cardboard or newspaper begin layering whatever materials you have collected until you have reached a height of at least 18”. Higher is even better; as your layers decompose, the height will dramatically decrease. When I’m making dinner, I rarely follow a recipe; building a garden is similar. Exact proportions are just not necessary. Although not a requirement, I do sprinkle a very thin layer each of bone meal and blood meal to add phosphorous and nitrogen, respectively. The blood meal also helps to speed decomposition.
The top layer of your lasagna garden should be finished compost. This can be compost you have made yourself, or purchased from a garden supply store. Recycling centers often sell leaf compost very inexpensively. This is the layer in which you will plant your seeds or seedlings. After your plants are several inches high, you may add mulch to preserve soil moisture and keep weeds from sprouting. Yearly maintenance involves adding a new layer of material to the top of your garden such as wood chips, chopped leaves, or weed-free hay or straw, preferably in the autumn. And now you are well on your way to building a garden with healthy soil that will produce nutrient-dense produce!