A few months ago, we highlighted the UN's report on the lost of global biodiversity. One topic in this post led to many questions and discussions - how can individuals manage their lawn to promote biodiversity?
This article, written by Francesca Singer provides guidance and tips on biodiversity promoting lawn management.
When you hear the word "biodiversity," the last thing that comes to mind is the image of a lawn. That's because the lawn care industry sees nature as a thing to we need to tame, control, and manage. But it's possible to have both a healthy lawn and a biologically diverse yard. Here's some guidance on how to cultivate biodiversity through your lawn strategy.
What is Biodiversity?
The level of biological diversity in an environment is determined by how many types of organisms share a space. If we're talking about a patch of forest or wetland, there's a highly evident level of biodiversity. But often, residential lawns also represent a type of monoculture — a manicured carpet of green a single turfgrass variety, with synthetic fertilizers and weed-killers enforcing the uniformity. In this kind of environment, even the occasional weeds tend to be the same. Ecologists worry that this type of monoculture helps to create biological deserts. Their lack of biodiversity makes them more susceptible to pests and diseases.
Lawns don't have to be monocultures, but a change to a more biodiverse expanse won’t happen overnight. Creating a biodiverse lawn begins by shifting to a different mindset.
Adding Biodiversity to Your Yard
Avoid Chemical Pesticides
Most homeowners use a large number of chemical pesticides to control the insects that plague lawns. From chinch bugs to grubs, insects pose a threat to a lush, green lawn. One of the first steps to encourage biodiversity is to recognize that not all insects are problematic. A biodiverse lawn offers built-in pest control through beneficial insects and birds that take care of pests. When you do need to pull out the big guns. use products that are both effective and organic, such as neem oil or diatomaceous earth. Want to get rid of mosquitoes? Put up a bat house. A single bat can eat up to 1,000 insects an hour.
Feed the Soil
One of the worst mistakes we make with our lawns is using a “weed and feed” strategy to kill weeds. We're talking about chemical herbicides and fertilizers. This approach may help the grass plants, but it completely ignores the underlying soil, where biodiversity begins. Healthy soil is full of life, from earthworms to beneficial organisms that keep pests in check. Chemical fertilizers do nothing to cultivate good soil and tend to run off into bodies of water where they damage the ecosystem. By leaving lawn clippings and mulched leaves on your lawn after mowing, you allow those nutrients to return to the soil. Applying compost to the lawn will also nourish the soil naturally.
Go Native With Turf
There are no hard and fast rules stating that your lawn must be entirely made up of one species of grass. The region where you live and the shade in your yard will determine which species of grass will perform best. There are a wide variety of native grasses that you can plant in place of the popular turf grasses we see most often in yards. Native grasses offer some distinct advantages. They add hardiness, reduce the need for irrigation, provide pest and disease resistance and, of course, encourage biodiversity. They may be more difficult to establish because they must be sown as seed instead of laid as sod, but the benefits they offer are vast.
Let Clover Take Over
You may think of clover as a noxious weed, but when people give in and let it have its way, the results can be surprising. Dutch white clover (Trifolium repens) was once considered a sign of a healthy lawn. Its seeds were included in bags of turfgrass seed, until a uniform lawn came into vogue in the 1950s. As sustainability-minded homeowners have sought out ways to make their lawns more biodiverse, it has made a comeback in the form of mixed grass-clover lawns or pure clover lawns.
For a thick, green cover through summer with minimal need for irrigation, clover is a winner. It remains vibrant until the first frost and then stages a dramatic comeback in the spring. White clover tops out between 2 and 8 inches tall and needs no mowing unless you prefer a tight, clean-cut look. Best of all, clover attracts beneficial insects such as bees and creates its own fertilizer, as a nitrogen-fixing legume.
The only downsides to a clover turf are that it stains clothing more than grass and you need to reseed it every two to three years. But mixed with grass, it's durable enough to withstand high traffic and can reseed itself.
Encouraging existing clover patches, seeding, or doing a combination of both is enough to establish a mixed clover lawn. To encourage clover patches, mow patches of clover with the blade set low – from 1.5 to 2 inches. This will help the clover outcompete the turfgrass. Seeding in early spring or mid-fall is the best way to guarantee success, and double the volume of seeds you sow in shady areas. After sowing seed, water the lawn lightly each day until seedlings are visible.
Add a Water Feature
Most people find the sound of falling water soothing. For wildlife, having a water source to sip from during summer and drought can be a lifesaver. To avoid stagnant water that can breed mosquitoes, add a feature that flows such as a birdbath or waterfall. Birds, squirrels, and even bees and butterflies benefit from a bit of water during the driest months. You can install an inexpensive water feature over a weekend in just a little time, so don’t be deterred by fear of a big, costly project. Water features today can be powered by battery- or solar-powered pumps, which are both lightweight and portable. If a fountain with a pump is out of the question, a standalone birdbath is another option, though you may want to add an agitator.
Incorporate Native Plants
You don't have tear out large areas of turf to accommodate a vegetable garden or more flower beds. Simply replace some of your annual plants with perennial natives that will increase the biodiversity in your yard. Native plant species feature flowers and seeds suited to local insect and bird populations. By planting specific species such as milkweed, you can contribute to the wellbeing of a species suffering from habitat loss–in this case, the monarch butterfly.
Planting native plants strategically so that something is always in bloom from early spring to late fall is another foolproof way to make sure your yard is a hotbed of pollinator activity. While spring and early summer provide a banquet of options for pollinators, late summer through fall can be a time of food scarcity, and blooming natives are a lifeline for our insect friends.
Supporting Biodiversity as Winter Approaches
One of the easiest things you can do to help support biodiversity–and pollinators in particular– is to delay your fall cutbacks and cleanups until winter has set in. Leaving flowers and seed heads on plants until the end of autumn provides valuable food resources for insects and animals alike. Using leaf litter as mulch in beds can provide vital winter habitat to native bees, and some species of butterflies hibernate on shrubs in either mature or chrysalis form.
Provide a Certified Wildlife Habitat
We’ve discussed putting up bat houses, and we all know about birdhouses, and something that has grown in popularity is bee houses. The latter is only a good idea if you are willing to invest the time to educate yourself about how to care for the bee house. A more comprehensive (and fun) way to turn your yard into a wildlife shangri-la is to create a certified wildlife habitat. It’s easier than it sounds, and once you are certified, you can put up a sign in your yard that indicates your yard’s status as a certified wildlife habitat. If you can influence neighbors to do the same, then you’re truly helping to create the change necessary to cultivate biodiversity in our urban areas.
No matter which strategy you begin with, there are many simple, low-cost, high-impact ways to cultivate biodiversity while managing your lawn. By taking a different approach to lawn care, you can transform your lawn into a haven for nature and humans alike.
Francesca Singer is a botanist and landscaper who uses only organic solutions in her garden. Her garden is filled with a compost bin and herbs and native plants that attract pollinators.