How to Create an Eco-Friendly Rain Garden

This has been a particularly wet and snowy winter in northern Indiana, where I live. When it isn't snowing lately, it has been raining. Walking across my backyard is like walking across a huge, muddy sponge. The only advantage I see to this situation is that nature is showing me the perfect spots to incorporate rain gardens into my landscape.

Rain gardens are a growing trend in home and business landscaping, and an excellent way to take advantage of the water that runs off from the roof or driveway into your yard. Studies show that up to 50% of water pollution is a result of the chemical pesticides and fertilizers that we put on our yards and gardens. By creating a rain garden, you reduce the amount of storm water that rushes into the local streams, rivers, and lakes, since the water filters naturally and slowly into the ground.

A rain garden differs from a regular garden in that it is saucer shaped, not flat or mounded. Strategically placed where rain naturally collects or runs off in your yard, rain gardens are virtually maintenance-free gardens once they become established. Forget the exotic flower varieties that require lots of attention, and fill your rain garden with plants native to your area to create a beautiful rain garden.

Choose trees, shrubs, and low-maintenance perennials that have deep root systems that will provide channels for the water to flow into. Native plants will also attract butterflies and create a mini-wildlife preserve in your own yard. A well-designed rain garden will not create a haven for mosquitoes, since the water should soak into the ground in a couple of days, and it takes about a week (at least, in this part of the country) for a mosquito egg to hatch and grow into a pestering, biting adult.

You need to insure that the spot you have chosen will handle the storm water. Dig a small hole before you dig the whole garden, and fill it with water. Watch how quickly the water soaks into the ground; if the water is still there after several hours it may not be a good spot for a rain garden without some soil amendment.

You will also want to avoid locating your rain garden in a spot that will get water runoff that contains a large amount of road or sidewalk salt in the winter. If these are the only spots you have that are suitable for a rain garden, plant salt-resistant varieties native to your area.

To create a rain garden you need to dig a shallow hole in the spot where water runs off your roof or driveway and into the yard. (Be sure to check for buried utilities before you start digging). This spot needs to be at least ten feet away from the basement of your home. To estimate the size of rain garden you need to handle the storm water, figure the square footage of the area where you have the runoff and divide by 10. For example, if the surface of your roof is 700 square feet, your rain garden needs to be 70 square feet in size to adequately handle the amount of water it will receive. Dig a shallow bowl-shaped depression that is about six to eight inches deep. The bottom should be flat, and the edges tapered up to meet the grass, so your hole resembles a saucer.

Once you've determined a good location for your rain garden, and have dug out the earth, fill the spot back in with a mixture of 20% topsoil, 20% compost, and 60% sand. Now you're ready to fill your rain garden with trees, shrubs, and/or flowers that are native to your local ecosystem. Native plants will be able to establish the necessary root system to enhance filtration, and will require little care after they are established. Non-native species will work, but will require extra cultivation.

Water your rain garden immediately after planting and once a week, unless you have had at least an inch of rain during the week. After the rain garden is established, you will seldom need to give it any additional water. Maintenance will require only a small amount of weeding and thinning. You can mulch your rain garden if you want to give it a more finished look. Native plants will not require as much fertilizer or pesticides as non-native varieties will demand. Could there be an easier way to create and care for a beautiful garden in your yard that is also environmentally-friendly?