Maintenance and Monitoring
During the first year , plantings should be watered regularly in order to allow the transplanted vegetation to establish . Irrigation should be gradually reduced over the establishment year and eventually turned off , only to be used in the future during periods of drought . Assure a 2-4 inch layer of mulch is present , this may require annual additions of mulch before the growing season . This will help to reduce the occurrence of weedy plant growth . Fresh mulch also improves the aesthetic overtime as older mulch breaks down and changes color .
The rain garden will need to be routinely maintained to remove unwanted plants ( i . e ., weeds ) and control the spread of planted vegetation . During the growing season , overgrowth should be removed as necessary to maintain the aesthetic appearance of the garden and prevent competition between plants . At the end of the growing season , dead plant material should be removed to promote healthy plant growth in the following season . The berm should be periodically maintained over the life of the garden by replacing any soil that ' s been lost to erosion or animal activity over the years ( Three Rivers Rain Garden Alliance ). Overall , maintenance varies by site and the overall desired appearance of the garden .
In addition to maintenance , monitoring of the rain garden ’ s efficacy is encouraged . A simple method to determine efficacy is to visit the garden directly after a rainfall event and record how long it takes for the collected water to fully drain . Charleston County states that these types of infrastructure should drain within 48 hours ( Charleston County Stormwater Program Permitting Standards Manual , 2017 ). This can be determined through visual observations following a rain event . For advanced methods , a well point can be driven 4 feet into the soil and outfitted with a Levelogger located below the soil surface to continuously track drainage . The data gathered from the Levelogger should be compensated with barometric pressure readings .
Figure 8 . General design a full sun rain garden .
36
NATURE-BASED SOLUTIONS MANUAL FOR KIAWAH ISLAND