How to Grow a Living Mulch for Your Garden

Fall preparation can create a living mulch in the spring.

Mulching a garden keeps the weeds down, regulates soil temperatures, reduces erosion and conserves moisture. A living mulch, such as red clover or alfalfa, can add nitrogen to the soil. Hairy vetch, another ground cover, works as a traditional mulch and provides a haven for beneficial insects, especially lady beetles and bees.

Things You'll Need

• Tiller
• Pitchfork
• Newspapers
• Hairy vetch seed
• Rake

Instructions

1. Prepare your established garden bed in late summer or early fall. Till the soil and add organic matter. Or stab the soil with a pitchfork at 1-foot intervals, rocking the fork a couple of times, and add a fresh layer of homemade compost.

2. Prepare a new garden bed with a modified lasagna method. Put down a thick layer of newspapers, followed by a layer of dried leaves or weed-free straw and a layer of compost, homemade or purchased at a lawn and garden center by the bag.

3. Hand-sow the hairy vetch seeds, about the size of peas, heavily over the bed area, because a percentage of seeds won't germinate; they may germinate in subsequent years. The thicker the hairy vetch the following spring, the fewer weeds you will have.

4. Rake the seeds lightly into the top layer of soil, followed by a gentle watering. If rain is forecast in a few days, skip the watering.

5. Watch for the hairy vetch to begin to emerge in early spring. Till the vetch into the soil to act as a green manure, mow it off or let it grow to cover the plot in a thick growth. When it begins to bloom, look for beneficial insects such as lady beetles.

6. Plant your spring garden directly into the vetch if choose not to mow or till it. As you get into the plants, you'll find the vines can be pulled back to clear a spot for your plant. Or you can remove enough hairy vetch to clear a spot so the plant will get enough sun. If you are planting seeds, remove enough hairy vetch for your rows but leave the rest in place.

7. Leave the hairy vetch to die back and turn brown as the weather gets hotter. Allow the dead material to continue to keep weeds down and conserve moisture the rest of the season. Leave the dried vetch as is at the end of the planting season and plant more, or rake it up and add it to the compost pile.

Tips & Warnings

• This type of gardening is not for the faint of heart. It can look messy, and if you're used to tidy rows, it takes some getting used to.

• Hairy vetch, a legume, adds nitrogen to the soil. Add an inoculant to maximize the nitrogen fixed on the roots.

• Some of the seeds you plant may not germinate until the next year. So if you decide you don't like this method, you may continue to find stray plants each year. They are easy to pull up.

• Hairy vetch withstands a lot of trampling. Despite its lush and soft look, avoid walking barefoot through hairy vetch. You may step on a bee.

References

• Washington State University Extension: Cover Crops for Home Gardens in Western Washington and Oregon
• University of Illinois Extension: Cover Crops for Vegetable Gardens