Who Likes Lasagna? Your Plants Do!
by Sharon Kimmelman, 09-05-12
Have you ever made it? If not, you’ve probably eaten it. It’s a meal of layered ingredients: pasta, filling, sauce, cheese. The layers are distinct when you assemble them. During the cooking, layers blend somewhat but remain distinct. Well, garden plants have to eat, too. Over the growing season, through their root systems, plants take up dissolved minerals and nutrients with the water. This ‘food’ needs to be replenished.
The Lasagna Garden Technique is a no-till, no-frills method of restoring soil fertility and building precious topsoil. The idea that we need to turn over the soil is unnecessary and detrimental, except in the most extreme circumstances of impenetrable or clayey soil. It’s important to remember that the soil itself is a living ecosystem teeming with insect and microbial life. They place themselves on the levels and in the areas favorable to their specific needs. Flipping the soil over and mixing it like cake batter destroys this highly structured organization. It is this invisible behind-the-scenes activity and soil structure that offers the real benefit to plants.
Being lazy isn’t all bad. This is the classic lazy gardener’s approach. Use it to top off a raised bed or convert lawn to garden. It’s good for the soil and easy on your back. It’s not rocket science; it’s rock science. Plus, it benefits our garden by using up the compost so we don’t have to spend $$$ buying bags of pre-packaged, plastic bagged stuff from far away, using precious fossil fuels to have it shipped here. Peat moss is a non-renewable resource dug in and shipped from Canadian bogs. Each of us can choose local, low-tech, high return approaches. This is definitely one!
Lasagna Gardening has multiple benefits. It:
- uses organic waste materials immediately
- builds up the soil level
- sequesters carbon
- preserves the strata of microorganisms
- improves soil fertility
- holds water, slows evaporation and run-off
- blocks out weeds
- keeps root systems cool
What you need is a stack of newspapers and / or corrugated cardboard, unfinished compost, water, hand pruners, a shovel, and a trowel.
Here’s how to start on a plot with mostly overgrown weeds.
- Clip and discard any developed seed heads.
- Clip the plants off at the soil level leaving the roots in place. Lay the tops down (they have pulled up nutrition to the surface, so use them to your advantage).
- Lay down a barrier of newspaper (4+ sheet thickness) or cardboard over the whole area.
- Wet down the newspaper so it doesn’t move around. (I soak the cardboard in a barrel so that it is more flexible and easier to mold.) Dig out any plants or perennials you wish to keep and replant higher or paper around them.
- Add a 4 – 6″ layer of unfinished compost onto the entire area. Identifiable scraps will breakdown over time, as the quintessential ‘slow release’ soil nutrient amendment.
- Water deeply.
- Repeat Steps 3-5 to build up the soil, if needed.
- Top off with a layer of newspaper or cardboard.
- Add a 1-2″ layer of mulch (straw or wood chips).
Without the sun, the grass and other roots systems will decompose leaving rich a soil habitat. To plant, simply push the mulch aside a bit, cut an ‘X’ or a slit in the paper layer, peel back the paper, make a small hole or valley, place a handful of finished compost in it, and either place a seedling or your seeds. Firm the soil. Flap back the newspaper (if it’s intact). Pull the mulch back around the stem or opening. Water the area to settle the soil around the plant or seeds. Voila! It’s so easy. Over time, the plant roots will ‘knit’ the layers together expanding the healthy soil habitat.
The uppermost paper barrier and the mulch keep the roots cool, slow evaporation, and keep the leaves from direct contact with the soil. That’s similar to undisturbed wild areas. Some gardeners use the newspaper layer only the first time because the thick layer of mulch on top keeps weed seeds from sprouting. Some folks add minerals, organic nutrients, biochar, etc to the compost layer.
As Dr Paul Rowan, DVM, says regarding cat care, “Stick as close as you can to nature and you’ll never go very far wrong.” This statement is globally applicable.
Doing this garden prep in autumn, the material has the whole winter to rot, but you can still do it in the spring just before planting. I’ve done both. Don’t lose this season.
Good practices ripple forth benefits broadly. Feed your garden better and you will eat better, feel better, get healthier, improve the environment, and set a good example for others. As long as you return your food scraps to the garden your plants will be well nourished, and so will you!
(Learn to identify the most common garden ‘weeds’ in our garden. Some are delicious and nutritious ‘wild edibles’, a much more dignified term and quite true. More about that in a later article.)