BY BARBARA STORZ
Rain gardens offer a way to reduce rainwater runoff, which contributes to flooding. These gardens filter the runoff and lessen the amount of pollutants that enter our waterways. With the right plants, rain gardens support wildlife.
A rain garden is an enhanced low spot in the garden, preferably at least 10 feet from yours and your neighbor’s home. Channel water to the garden from rain gutters, driveways and other low points in the yard by building swales that lead to the rain garden. You want to capture as much water as will sink into the soil in the 24 hours after a storm event.
A rain garden will be dry most of the year. You can mulch the garden with about 3 inches of bark mulch and place large rocks along the berm.
Native plants will work best and will tolerate the temporary excessive water. A berm along the top edge is a good place to plant native grasses and small native shrubs. Keep the slope at a minimum of 1 inch to every 4 feet, 6 inches (about 2 percent). Be sure to avoid putting the rain garden over a septic tank or underground utility lines. You can call 811 (national number) to have your utilities marked before digging.
Plants such as our native turk’s cap work well along the top edge of a rain garden. Lantana will also tolerate the rain garden along the top edge. Shorter grasses, native salvia, Mexican trixis and Mexican petunia can fill the lower areas of the rain garden and support butterflies and hummingbirds.
When we have a heavy rain event on clay soils, very little of the rain initially penetrates the soil, which causes flooding and contributes to pollution. So, if we slow the water with a rain garden, we can keep more of it for our own plants and the wildlife that enjoy our native plants.
Our clay soils work well for a rain garden because they slow the percolation of water which allows plants to filter the water. Let’s create rain gardens and reduce the amount of water run off.
If you would like a list of native plants, stop by the Growing Growers Farmers Market from 9 a.m. to noon today and speak to a Master Gardener. The market features locally grown fruits, vegetables and herbs, along with grassfed lamb and goat’s milk cheese and farm products. It is located at Firemen’s Park on the corner of 1st Street and Business 83 in McAllen.Creating rain gardens is a great way to reduce the amount of water run off to the street.
Barbara Storz is a local horticulturist. You can listen to her garden show on at 7 a.m. Saturdays on 710 KURV Radio. You can also contact her via e-mail at firstname.lastname@example.org.