MASTER GARDENER PROGRAM — MGs in the News
Published in: OregonLive.com • January 8, 2016, 2:41 PM
You can easily improve soil fertility, suppress weeds without chemicals and prevent wind and rain soil erosion by planting cover crops in your home garden.
What exactly is a cover crop? Think “green manure,” say Clark County Master Gardeners. Cover crops are living plants that grow for a short time to cover and protect the soil when it is not being used as a vegetable garden or flower bed.
Don’t know where to start?
Attend the free workshop on growing cover crops hosted by Clark County Master Gardeners from 10 a.m. to noon on Saturday, Aug. 15, at the Washougal Community Library, 1661 C St. No registration is needed.
You will learn what cover crop is appropriate for a garden, when to plant it and when to harvest or till it for the best results.
The workshop leader is Ian Wilson, owner of Portland Edible Gardens, whose experience includes working on farms, gardens and orchards in the U.S. and Argentina. He earned an advanced certificate in ecological horticulture from the Organic Farm and Garden Apprenticeship program at the University of California Santa Cruz.
Here are four benefits of cover crops:
- They help retain soil moisture, prevent erosion and attract beneficial insects, say experts.
- Before planting the garden, cover crops can be tilled into the soil to improve tilth and boost nutrients.
- They also can be harvested and composted or used as dry mulch.
- Cover crops can be an important factor in crop rotation and also attract and feed earthworms and soil microorganisms.
Many plants can be used as a cover crop, depending on what benefits are most desired. Some commonly used cover crops are:
Legumes will fix nitrogen in the soil; some use their long tap-roots to “mine” nutrients from well below the surface. They do well in cool climates when planted in spring and fall. The legume family would include crimson clover and red clover, hairy vetch and common vetch, alfalfa, fava beans, Australian winter peas, medec and soybeans.
Grasses and cereals tend to reduce the loss of soil nitrogen through excellent protection from soil erosion. Grasses are quickly established and very effective in controlling weeds. The ones used for cover crops include annual ryegrass, rye, wheat, barley, sorghum, sudangrass and oats. Grasses and cereal may reduce the overall nitrogen available for subsequent crops, so many gardeners use a seed mixture of grasses and legumes.
Broadleaf plants, including buckwheat, rape, mustard, turnips, daikon radish and oil seed radish, are also used as cover crops. These plants are more suited to warm weather planting.
Cover crop seeds and seed mixtures can be purchased or ordered from garden centers or online sources. Excess seed can be stored in a cool dry area for up to a year.
It is important to plant the seeds at the correct time — usually as soon as the harvest is complete — and when to harvest or till, which is before they go to seed.
For more information about the workshop, contact Erika Johnson of the WSU Extension Clark County Master Gardener program at 360-397-6050 ext. 5738 or Erika.d.johnson@wsu.edu.
— Information provided by Clark County Master Gardeners
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