How do I make a rain garden?
It's not complicated. Just follow these easy steps:
- Determine the size of your rain garden by estimating your roof's square footage. Your rain garden should be about one third the size of the area providing runoff.
- Choose a spot at least 10 feet from your house and downslope from your downspout or sump-pump outlets.
- Before digging, make sure you won't encounter any utility lines. Contact 1-(800)-DIG-RITE so utility lines can be marked.
- For a 200-square-foot roof area, dig a shallow depression 6-to-8 inches deep and 10-feet long by 7-feet wide. Slope the sides toward the centre. Adjust the square-footage measurements if your roof is larger or smaller.
- Test the overflow pattern to be sure it runs away from your house. Do this by filling the depression with water and watching the overflow. If necessary, dig a shallow channel to direct water away from buildings and toward the street.
- Direct your downspout or sump-pump outlet to your rain garden depression, either by digging a shallow channel or by piping runoff through a buried 4-inch, black-plastic drainpipe.
- Now you are ready to plant the native plants recommended below. The designs place taller plants in the centre of the design and shorter ones along the edges. Adjust plant numbers if your garden is larger or smaller.
- Put a 3-inch layer of untreated shredded hardwood mulch on the bare soil around the plants to conserve moisture and keep your design looking neat.
- Water your planting every other day for the first few weeks or until it shows growth and good establishment.