Get Ready to Close Up Your Garden with Cover Crops
By Dianne Venetta
Just when you thought your work was over, the growing season is winding down, the days are growing shorter, the winds colder but your garden still needs your attention.
Huh? What can the garden possibly need now?
Other than “blankets” to keep it warm and snuggly as the temps drop, your garden wants to keep busy and one of the best ways it can do so is by amending its soil. How does it do this?
Cover crops. These will vary depending on your region and can range from rye to legumes, brassicas to flowers but most important—they all have a purpose. Say you’re an organic gardener (of course you are!) and you want to enrich your soil with organic matter. You live in a temperate climate and can grow year round…why not plant a crop of beans? They’re an excellent choice because, not only do they like it warm, their wide leaves will shade the ground for weed prevention and their roots will put nitrogen into your soil.
But let’s say you live up north and beans won’t survive the long harsh winter. You would best be served by a heavy seeding of rye in your garden. Not only will it improve your soil, but it’s cold tolerant and thick enough to provide great weed prevention. Gotta love that! Come spring, simply till it back into the soil after it flowers for maximum soil improvement.
Both beans and rye are considered “green manure” because they improve soil fertility in the way of nitrogen and nitrogen keeps everything green! But some cover crops can do more than improve soil and prevent weeds. Planting mustard has been shown to suppress fungal disease populations through the release of naturally occurring toxic chemicals during the degradation of glucosinolade compounds in their plant cell tissues. The Brassica species can also release chemical compounds that may be toxic to soil borne pathogens and pests such as nematodes, fungi and some weeds.
And speaking of nematodes, planting marigolds can prevent nematodes from reproducing—a good thing—because these microscopic beasts can kill your vegetable plants from the roots up. Very hard to fend off when you can’t see them. Another nematode-eliminating method of cover crops comes in the form of paper crop covers, known as “solarizing your soil.” By covering your beds with plastic paper (red, black or clear), you can eliminate the bugs beneath the ground. I like to think of this as my very own rendition of the sun-baked oven where you trap the heat, heat the soil, fry the varmints and prepare for planting—pest-free!
As if that isn’t enough reason to plant a cover crop, consider the benefits it will provide against soil erosion. A dense planting of any cover crop will physically slow down the speed at which rain makes contact with the soil surface, thereby lessening the amount of soil that can runoff (and out of your garden!). Then of course there’s the added benefit of soil porosity created by the vast root network. I do love a multi-tasker.
So whether you’re covering crops with paper or growing crops for cover—think of them as a down payment on fertility come spring. Happy gardening!