One of the most important parts of gardening is maintaining healthy soil. This is most evident in the vegetable garden, as well as with many other aspects, from annuals to shrubs.
Whenever there is bare soil, weeds take advantage and reduce nutrient availability while rain can leach the rest. Cover crops are a great way to protect the soil while also adding organic matter and encouraging biodiversity.
A cover crop is any crop that is planted but not considered a cash crop. While cover crops are becoming more and more common in agriculture, they are still underutilized in home gardens.
The idea of cover-cropping is an age-old practice, but only recently have we started to understand its effects on soil fertility and health. It is derived from the idea of crop rotations in relation to soil health. Growing the same crop year after year depletes the soil. Throughout history, those in agriculture have been working to find ways to increase productivity while lowering costs. For homeowners, this provides a practice that helps improve the ecosystem that is the garden.
When it comes to the average homeowner, the lack of utilization of cover crops in the garden is surprising. Not only in vegetable gardens, but also in ornamental gardens, cover crops have a wide range of uses and benefits.
Whether it is weed suppression or attracting pollinators, cover crops are an excellent way to increase the productivity of the garden, in general. And with fall fast approaching, the time to plant cover crops is impending.
The most important thing to know when choosing a cover crop, or a mix of species, is what is the need and the purpose. Different species provide different benefits and understanding these is important when choosing the species.
It is also important to know what season certain species grow in order to properly rotate. For example, forage radish, or tillage radish, is excellent in breaking up hard soils and increasing soil drainage. A borage cover can add some calcium to the soil while buckwheat is a great source of potassium. Both attract pollinators as well.
Rotating between legumes and grasses helps increase nitrogen in the system and reduces leaching nitrogen as well. One must also determine the season the crop is being planted. The fall and winter are usually the time of lessened activity for many plants, which, in turn, provides the best time (with the most choices) for cover crops to be used.
There are many examples of fall covers, such as Crimson clover, which is a legume. Legumes are great for adding nitrogen to a system, and clover provides plenty of food for pollinators come spring time. Daikon radishes are a quick grower that help break up compacted soil and add much needed organic matter.
Grasses such as annual ryegrass or hairy vetch are quick growers in the fall and scavenge nitrogen, helping to prevent leaching as well as.
One of the pests that is the most frustrating in the garden is the nematode, a microscopic, parasitic, nonsegmented round worm. Nematodes infest certain plant roots and can significantly reduce the productivity of the plant in question.
Unfortunately, there are few treatments available to homeowners. But the use of a marigold cover can help to repel the nematodes. Certain mustards and other brassicas have some effect on nematode control, but the data has been inconsistent. They do have some effects on other soil-borne diseases and are good weed suppressors, though if allowed to seed, can become a weed themselves.
As the growing season comes to an end and the vegetables are harvested, cover crops help prepare the soil for the next growing season all while protecting the existing soil from weeds and erosion.
Whether used as a green mulch or a green manure, understanding both the benefits of cover crops in the garden, as well as the drawbacks, is an integral part of a healthy yard.
As with any garden, proper planning is important to encourage the most productivity from any raised bed or vegetable plot. Protect the soil you have as this is the most important part of any yard.