Garden Friday – Winter Cover Crops
In the rainy Pacific Northwest, the surest way to deplete your soil is to leave it bare during the winter. The forest naturally provides a canopy and cover of dead leaves to slow down the rain washing away vitamins and minerals; without it, you are asking for junky soil full of lots of weeds if nothing is done.
Luckily, we can grow some veggies year around. But, if you don’t put in a winter garden, there are basically 2 options.
The first is to cover your beds with straw and leaves to slow down the runoff.
The second is to plant cover crops that can withstand the winter. Most winter cover crops need to be planted 4 weeks before the first hard frost to have time to establish themselves. If this is done, they will grow until the hard frosts and begin growing again in early spring. The exception is cereal rye which can be planted right up to a frost. So even though I just planted the last of mine this week, you still have time along the Wasatch front.
What did I plant? Well, legumes are popular choices because they both add organic matter AND ‘fix’ their own nitrogen from the air which results in more fertile soil, especially if you turn under the plants as green manure. At the end of September, I planted several different snap peas; if I’m lucky, they will actually produce edible peas in a few weeks before the hard frosts and then I can turn them under in early spring. If I’m unlucky, I won’t get any food out of it this season but will improve the soil for next.
In my raised bed that is less than a year old, I inter-planted Austrian peas (also sometimes called a field pea) and cereal rye last weekend. Again, the Austrian Pea has the benefit of legumes fixing nitrogen; it is a hardy field pea that handles winter well. The cereal rye is super hardy and will provide some support for the pea plants while also providing soil structure stabilization/erosion control.
One thing to keep in mind while using cover crops as green manure is that you must kill the cover crop before it matures so the crop itself doesn’t turn into a weed. In the early spring, I’ll cut down the Austrian Pea and rye, wait a week, and then turn it under after a few days of sunshine when the soil isn’t completely waterlogged.
Do you plant cover crops in your garden? Which ones and when?