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How To Successfully Collect Rainwater for Your Garden

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How To Successfully Collect Rainwater for Your Garden

Mary, Mary quite contrary, how does your garden grow? You know, Mary your garden isn't going to be successful without water. Two hydrogen atoms and one oxygen atom combine for a powerful garden tool. But what if you live in an area where rainwater is scarce, or you want to cut down on municipal or well water use? You can collect rainwater to use in your garden.

Here's what you need to know to make your own rainwater collection system:

Collect your supplies:

If you don't have gutters on your roof already, consider installing some to collect rainwater. As this can be an expensive proposition, consider putting gutters on one part of your roof at a time. Start with the part of your roof closet to your garden.

  • a downspout diverter long enough to connect your gutter to your collection barrel
  • I used a plastic 32 gallon garbage can for my collection barrel, but a wood, steel, galvanized metal, or concrete barrel can also be used. You need a lid too.
  • screen large enough to cover half of your lid
  • silicone caulk
  • saw

How to Collect Rainwater

The simplest way to collect rainwater is to place a barrel outside and let the rain pour in. But gutters attached to your roof allow you to collect exponentially more rainwater. Consider this: One inch of rainfall will collect 600 gallons from a 1,000 square foot roof, and a 4,500 square foot will receive 2,800 gallons. If you do not already have gutters, check out this DIY link to learn how to install them.

The rainwater should be collected as close to your garden as possible to make the task of bringing the water to the garden easier. Also consider that your collection barrel needs to be placed on a flat surface to keep it steady and avoid tipping over.

Looking at your lid, imagine a straight line across its diameter. Now, imagine that line curving down to make a U shape that connects to the other end of the straight line. Using the saw, cut out this half circle shape from the lid. Cut a piece of screen large enough to cover this open lid area with an inch or two extra all around. On the inside of the lid outline the cut out area with silicone caulk and affix the screen to cover the opening.

This screen covered opening allows rainwater to flow into your barrel while keeping unwanted debris and critters out. The lid should securely rest on the barrel but still be easy to remove to access the water.

Place your collection barrel as close to the gutter's downspout as possible. I had about four feet from where my gutter ended and my collection barrel was located. So, I attached a flexible downspout to the end of the gutter and rested the other end on the screen covered portion of my collection barrel's lid.

Up Your Game

If you're already successfully collecting water in a barrel, consider adding additional barrels. One way to collect rainwater using more than one barrel is to repeat the process outlined above using another downspout from another gutter.

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From the Organic Authority Files

When I wanted to add more barrels, however, I wanted them to all be in the same place near my garden. So, I connected multiple barrels using garden hose. Here's how:

In addition to the supplies listed above, you need a barbed hose fitting (a.k.a. brass barbed fitting). If you're adding one additional collection barrel then you need two barbed hose fittings; if you're adding two barrels then you need four. These are small metal gizmos that are most commonly used to fix breaks in garden hose. You can find one at any home supply store. For each additional barrel that you add you'll need 2-3 feet of hose.

Cut a hole in the side of the first collection barrel about 6-8 inches from the top. Use the barbed hose fitting to judge how large the hole should be. The larger end of the barbed hose fitting will go inside the barrel; the barbed end will be outside. Once it's in place use some silicone caulk inside the barrel to make it water tight. Fit the length of garden hose to the end of the barbed hose fitting that is outside the barrel.

Now, repeat the process of cutting a hole in the side of the barrel and attaching the barbed hose fitting for the second barrel. Connect the two barrels with hose. Repeat this process for each additional barrel that you add.

Beyond rain barrels

Gardeners in drought stricken areas such as southern California are receiving no rainwater from Mother Nature. In some of these areas municipalities are paying residents to rip out their water intensive lawns and replace them with drought tolerant landscapes. Gardeners in these areas need to consider low (or no) water landscapes; check out these links:

8 Tips for Gardening During a Drought

Drought Gardening Tips

Lawn-Free Yards

Related on Organic Authority

5 Wise Watering Techniques for Late (Late!) Summer Gardens

That's Every Inch: 100 Percent of Kansas Battling Severe Drought

Two-Thirds of U.S. Battling Worst Drought in More than 50 Years

image of rain on seedlings via Shutterstock

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