Collecting Rainwater for Gardens
As gardeners look for ways to conserve resources, rainwater harvesting is gaining in popularity. Capturing rainfall not only reduces dependence on municipal water supplies, but also provides plants with a natural, chemicalfree source of water.
Rainwater is usually better for plants than tap water, which is treated. It is naturally soft, free of salts and other additives. For gardeners, especially those growing vegetables or ornamentals, this can mean healthier plants, improved growth, and more produce.
The most common method of collecting rainwater is through a rain barrel system. These barrels are usually placed beneath downspouts to catch runoff from rooftops. A standard rain barrel can collect a significant amount of water from even a small rain event. For example, just one inch of rain falling on a 1,000-square-foot roof can yield over 600 gallons of water.
When setting up a rainwater collection system, location and safety are key. Barrels should be food grade, and placed on a stable, level surface and elevated slightly to allow for easy access to the spigot. It is also important to use a tightly fitted lid or screen to keep out debris, insects, and small animals. This also helps prevent mosquito breeding and keeps the water a bit cleaner. The use of Bacillus thuringiensis israelensis (Bti) dunks for mosquito control is a good idea.
Also consider an overflow management system. During heavy rains, a full barrel needs a way to safely divert excess water away from the foundation of the home. Many rain barrels come with overflow valves that can be directed into a garden bed, drainage area or link multiple barrels together for an expanded system.
As with anything, rainwater collection doesn’t work properly without regular maintenance. Barrels should be cleaned periodically, screens checked for clogs, and connections inspected for leaks. During the winter months, it’s highly recommended to drain and disconnect barrels to prevent freezing damage.
You can contact Laura Payne, OSU Horticulture Educator for Payne County via email at laura.payne@okstate.edu, phone at 405-747-8320, or in person at the Payne County Extension office, located at 315 W. 6th in Stillwater.