Tall Switchgrass
Panicum Virgatum
Type: Grass
Height: 3' - 6'
Exposure: Full Sun / Partial Sun
Bloom: Spring / Summer / Fall
Quick growing, spring wildlife cover.
What can you do to reduce stormwater runoff?
Gardening and Rain Gardens
A rain garden is a specially designed landscaped area that provides natural places for rainwater to collect and soak into the ground.
A rain garden allows the rain water to pool for a short period of time in the garden. As rain from rooftop areas or paved areas soaks into the ground, the water is cleaned by the plants and the soil microbes in the soil. This water can recharge the groundwater supply and release slowly without dirt or other pollutants.
All it takes is a little planning, a shovel, some plants, and a few stones. It is easy and can be installed in a few short hours.
Diagram of a Rain Garden
A rain garden allows stormwater to pool for a short time period in the garden. As stormwater soaks into the ground, the water is cleaned by the plants and the microbes in the soil. Stormwater is then slowly absorbed into ground, filtering dirt and other pollutants and replenishing groundwater.
Entrance:
The entrance prevents sediments from clogging the rain garden, filtering sediments uphill. Occasional maintenance includes removing trash, sediments, and debris to protect the entrance from erosion.
Wood Chips or Ground Cover
Filter Bed:
The filter bed is layer of sandy soil mix that helps store and filter stormwater. Filter beds are beneficial, and often necessary, where existing soil drains poorly or other site constraints exist.
Existing Soil:
Try to minimize compaction of the soil below the rain garden. Healthy biological communities within plant root zones help reduce the pollutants that reach groundwater.
Outflow:
The outflow is the specific place for excess water to overflow. The height of the outflow determines the depth of ponding. You can protect the outflow from erosion with more rigid material like rock.
Temporary Six-inch Ponding
Rain Garden Plants
Salt-tolerant
These plants are salt-tolerant, so you can plant them need walkways, driveways or other places to get salted during the winter.
Salt-intolerant
These plants are not salt-tolerant, so you want to avoid placing them in areas away from where you salt in the winter.
Are You Interested in Learning More about Rain Gardens?
Helpful Tips for Building a Rain Garden
- Choose the placement, shape, and impervious surface that will drain into the garden before you start digging. A rain garden will help reduce stormwater in an area up to 5 times its size.
- Make sure the garden depth is even throughout the bed. The garden should have gradually sloped sides.
- Uphill and downhill edges of the rain garden should be the same height. To do this, create a berm on the downhill side with soil or the sod dug out of the garden. Measure the height all across the down and uphill edges to ensure even height. This can be done with a string line level and measuring tape. Stake string at the high point of the garden and measure across to different areas of the berm.
- Use soil with high sand and low clay content. This increases the water retention capacity and increases drainage time. Soil can be amended. Compost should be added to help give plants a boost and enhance water retention.
- Try not to walk in the garden as much as possible. This will keep the soils airy and not compact. After planting, make sure to water and mulch the garden thoroughly. Line the entrance of the garden with pebbles and stones to protect it from erosion.
The plants need to be hearty and able to handle short periods of inundation after rain. Use of native and taller plants are preferable because of the pooling of the rain water.
Most of the time, soil will be well drained and dry. Look for plants that prefer moist or well drained soils.