By Kirsten Delamarter
Fifty years ago, thousands of Kentuckians celebrated the first Earth Day with anti-pollution demonstrations, environmental lectures and community clean-up events. The day launched a “wave of action,” with then-President Richard Nixon later that year signing into law pieces of landmark legislation that still guide environmental regulation: the Clean Air, the Clean Water and Endangered Species acts.
This year’s Earth Day will look different in the Commonwealth, as efforts to slow the spread of coronavirus prevent the large gatherings that marked the first celebration. Instead, many Kentuckians will spend the day in their own backyards — which creates its own opportunities for learning and celebration.
Here are some ways to care for lawns and gardens with an eye toward protecting and appreciating the natural world.
Test Your Soil, Prevent Water Pollution
Some of the nutrients found in fertilizers — such as nitrogen, phosphorus and potassium — are naturally found in urban landscapes. Taking the time to get a soil test will help you determine what levels these nutrients can already be found in your garden or lawn. The results of the test can guide responsible fertilizer use, saving you money and preventing water pollution.
Without such tests, homeowners and recreational gardeners often guess how much fertilizer their soil needs and apply it at the wrong times, said Amanda Abnee Gumbert, a water quality specialist with the University of Kentucky Cooperative Extension Service.
“When excess fertilizers are applied, the plants are unable to use all of the available nutrients,” she said. “These extra nutrients are then likely to run off or leach through soils during or after heavy rainfall.”
This influx of nutrients in water bodies can cause excess algae growth, in which the algae forms a thick mat on the surface of the water that blocks sunlight from aquatic life below the surface.
“As the algae dies, dissolved oxygen levels decrease in the water as bacteria use oxygen to break down the algae,” Gumbert said. “This results in low oxygen levels for things like fish, mussels, and aquatic insects – and these organisms may die.”
For more information about soil testing, contact your local UK Cooperative Extension Service office. All offices can assist farmers and homeowners with soil sample analysis at a reasonable cost. Find your local office here.
Avoid Pesticides with Companion Planting & Integrated Pest Management
Similarly to fertilizers, pesticides can enter streams, rivers, lakes and ponds and disrupt aquatic life.
“They can kill non-targeted species such as beneficial insects and aquatic plants that fish need to survive,” Gumbert said.
To avoid the need for pesticides, you can practice companion planting and integrated pest management, she said.
Companion planting involves the strategic planting of your garden, placing plants that “get along” well with one another in close proximity. Companion plants can improve the health of one another, enhance flavor or repel undesirable creatures.
Though the research on companion planting is still emerging and the success of certain relationships can be affected by local conditions, anecdotal evidence seems to point to several generally accepted pairings that can serve as a starting point. For example, pot marigolds can deter beetles from affecting asparagus, and mint can deter cabbage moths from vegetables in the cabbage family. You can read more about companion planting here.
You can also apply a combination of pest control tactics, or integrated pest management, after assessing the extent of your pest problem. These tactics can include chemical controls, such as pesticides, in addition to techniques like changing planting/harvest dates to avoid pests, rotating crops, trapping undesired creatures or protecting natural enemies of the pest. Read more about integrated pest management here.
Mow with Air Quality in Mind
Gas-powered lawn mowers can significantly contribute to air pollution, such as ground-level ozone. In fact, a single gas-powered mower emits as much hourly air emissions as 40 cars, according to the California Air Resources Board.
Ozone pollution forms in the heat of the day, when sunlight triggers a photochemical reaction between other pollutants in the air. If you do use a gas mower, mowing after 6 p.m. can reduce your contribution to this asthma-triggering pollutant, writes Roberta Burnes, an environmental education specialist with the Kentucky Division for Air Quality.
You can further reduce mower-related air pollution with your choice of lawn mower. Human-powered reel mowers are the greenest choice for small lawns since they require no fuel other than human energy and produce zero emissions.
The U.S. Environmental Protection Agency phased in emission standards for mowers in 2012, so mowers made before then produce more emissions than current models. While today’s gas-powered mowers are more efficient than those made 10 years ago, they nevertheless account for 24-35 percent of all non-road emissions in the U.S.
Technology has also significantly improved in the world of electric lawn mowers and other lawn tools. In the past decade, rechargeable batteries have become lighter and longer-lasting, and advances in motor technology have made electric lawn tools more powerful, according to a 2017 article in trade publication Lawn and Landscape.
A wide range of battery-operated mowers is available, and many can run an hour or longer on a single charge. For larger yards that take longer to mow, select a model that allows you to easily switch batteries when the charge is low and keep an extra battery on hand. Battery-operated mowers are quieter and lighter than their gas-powered counterparts, too.
Create a Native Plant Garden
Another way to help the environment while adding color to your landscape is by choosing native species. They’ve evolved over thousands of years to adapt to Kentucky’s soil and climate conditions, said Tara Littlefield, who oversees conservation efforts of both rare species and common native plants in the Office of Kentucky Nature Preserves.
“Native plants, when they grow our in our natural areas, we don’t have to fertilize them or put pesticides on them,” said Littlefield, who is also the president of the Kentucky Native Plant Society. “They’ve just evolved to flourish under those conditions.”
In addition to being easy to maintain and requiring fewer chemicals than horticultural species, native plants also benefit wildlife native to your area, including birds, bats and pollinators.
To add native species to your garden, Littlefield said, the first step is to assess your yard conditions — the amount of sun it receives and soil conditions. Then, look for a native plant nursery near you. Since different regions of the state have different soil conditions, your local native plant nursery can recommend species that will thrive. Check out Kentucky Native Plant Society’s website to find a local native plant nursery, as well as other resources.
Littlefield also encouraged Kentuckians to explore the native plants that might already be in their own backyards. Using iNaturalist, a smartphone app that uses your phone’s camera to identify native species, you can learn more about the “interesting little weeds that grow in lawns and edges of people’s yards,” she said.
“I think that’s also another interesting aspect of being at home more and looking at your yard — just discovering and enhancing and planting,” Littlefield said. “It kind of all goes together.”