Ground Covers: Protect Your Soil

Here’s all you need to know about when to use mulch, ground covers, or cover crops for the healthiest soil and garden.

| January/February 2019

  • A gardener adds manure to a flower border with a fork to improve soil health.
    Photo by GAP Photos
  • A young woman cleans dried leaves from a garden area in autumn.
    Photo by Neyya
  • Mustard planted as a cover crop helps remove pathogens from soil.
    Photo by Adobe Stock/Gang
  • Hairy vetch is a great ground cover.
    Photo by Adobe Stock/Tamu
  • When new strawberry plants are being established, mulch mats can help soil retain both moisture and warmth.
    Photo by GAP Photos/Paul Debois
  • Low-growing ground covers, such as thyme, are a great option for planting under trees, shrubs, and perennials.
    Photo by Antonella Lussardi

Most gardeners quickly learn that bare soil in a garden is an invitation for weeds to take up residence. Because few of us enjoy weeding, we cover up the soil as quickly as we can, often with bags of shredded wood. However, while mulch is a practical way to neaten your flower beds, it isn’t always the most eco-friendly option, nor the best choice for keeping soil healthy.

Purchased wood mulch takes energy to produce and distribute to your garden center. If it’s bagged in plastic, there’s an additional footprint for the packaging. According to David Nowak, senior scientist with the U.S. Forest Service, shredding trees for mulch hastens the process of releasing stored carbon into the atmosphere, so wood mulch — which we use in part to reduce the need for watering and herbicides — in some ways actually adds to your landscape’s ecological footprint. Jessica Gutknecht, a soil scientist with the University of Minnesota, says that while mulch is helpful when starting off for adding organic material to improve degraded soil, over time, it’s not as beneficial to soil communities and soil quality as living covers.

While some situations may call for mulch, if you want to create a healthy, eco-friendly yard, consider mulch alternatives.

When to Consider Cover Crops

Cover crops — temporary crops of annual grasses or legumes that protect and build soil — are most commonly used in vegetable gardens, where soil would otherwise be left bare after the harvest. Ajay Nair, associate professor of horticulture at Iowa State University, recommends using cover crops in your home garden for several reasons. In addition to holding soil together and preventing erosion, when cover crops are tilled in, they add organic matter and nutrients that help improve soil quality. They also provide habitat for beneficial insects, which can increase biodiversity and improve the health of your garden.

Belowground, the roots of cover crops break up compacted soil, which allows water and air to penetrate and creates paths that your next crop can follow to access nutrients deeper in the earth. Cover crops also provide food for soil microbes, which in turn feed your vegetables. Certain cover crops have additional benefits. For example, legume crops (such as peas, hairy vetch, and clover) fix nitrogen, reducing the need for fertilizer; and brassica crops (such as mustard and oilseed radish) help remove pathogens from soil.

Nair urges gardeners who are new to cover cropping to research the habits of the cover crops they choose, because certain types, such as buckwheat, grow quickly and can take over if you’re not vigilant. He recommends selecting cover crops that won’t overwinter, so they won’t run rampant in the spring garden.
You can till frost-killed crops in, or just fold them over, to create mulch that you can plant right into during the following season. Nair suggests trying a combination of cover crops to get different benefits from each, as long as you understand their habits and keep them from overtaking your garden. You must also consider crop rotation when choosing a cover crop. For instance, brassicas, such as broccoli and kale, shouldn’t be planted where a brassica cover crop just went in.

Subscribe today and save 58%

Get the latest on Healthy Living and Natural Beauty!

Mother Earth LivingRedefine beauty and embrace holistic living with Mother Earth Living by your side. Each issue  provides you with easy, hands-on ways to connect your life with the natural world -- from eating seasonally to culinary and medicinal uses of herbs; from aromatherapy and DIY cosmetics to yoga and beyond. Start your journey to holistic living today and you’ll discover all the best and latest information you want on choosing natural remedies and practicing preventive medicine; cooking with a nutritious and whole-food focus; creating a nontoxic home; and gardening for food, wellness and enjoyment. Subscribe to Mother Earth Living today to get inspired on the art of living wisely and living well.

Save Money & a Few Trees!

Pay now with a credit card and take advantage of our earth-friendly automatic renewal savings plan. You’ll save an additional $5 and get six issues of Mother Earth Living for just $19.95! (Offer valid only in the U.S.)

Or, choose Bill Me and pay just $24.95.

Facebook Pinterest Instagram YouTube Twitter