Many gardeners harvest rainwater in large barrels to use on plants and landscapes. In more arid areas of the country, collecting rainwater helps provide water for gardens during hot times of the year. It also provides a way to protect plants and landscape during periodic hard rains.
One of the benefits of using rainwater on plants is that it has none of the chemicals or minerals found in treated or tap water. Chlorine and other minerals can hurt plants. The rainwater also has a neutral pH, meaning there is no acidity. Though most people use tap water to water their plants, the chlorine and other minerals can affect plants that are more sensitive, such as orchids or bromeliads.
According to gardening expert Nigel Dunnett, using rainwater to water your plants actually creates drought tolerance because it is a natural form of water that reaches roots. The water then pushes salts and other minerals away from roots, creating a drought-tolerant plant.
Hard rain can hurt young seedlings and even established plants. Runoff can cause flooding and erosion of soil around plants, leaving roots exposed. You can cut out those risks by planting a windbreak or cover and incorporating walls or trellises in your landscape. Harvest rainwater by placing barrels at strategic locations near heavy runoff areas. This can protect plants from the damage heavy rainfall can cause.