Rain Barrel Basics: Prep, Placement, Pests

rain barrels

Rain barrel painting, like gardening, is a wide-open field. Stick with a theme or assign a barrel or section to each child. Or have a painting party. (Photo courtesy of The Environmental Blog)

The amount of rainwater that hits the roof of even a modest home is astonishing. For a 1,000 square-foot home, runoff from a 1-inch rain can top 600 gallons.

As more gardeners try rain barrels, the marketplace has responded with options both fancy and utilitarian. We bought 55-gallon barrels made from food-grade plastic in Nashville off Craigslist a few years back. The seller had drilled holes, installed spigots, and provided set-in cages at the top plus wide, segmented sections to attach to each gutter downspout.

In late fall, empty, rinse and turn them over. In setting up each spring, rinse the interior and fill to the tap to check for leaks. In cold climates, trapped water can freeze and expand, cracking the plastic. The seal that holds the spigot in place may deteriorate with time and the elements. Some silicone sealer will fix it.

Place rain barrels under high-volume downspouts, close to the house or outbuilding and near garden beds and other areas you’ll use the water. Elevate them on sturdy cinder blocks so a bucket fits under the spigot. We slip a garden hose segment over the tap to direct water to the beds, so a little elevation also goes a long way.

rain barrel

Cement blocks elevate rain barrels, allowing easy access and putting gravity on your side.

Mosquitos release their larvae in standing water, so rain barrels are mosquito magnets. As a first line of defense, cover openings with fine metal mesh or even old pantyhose.

Still, they will come.  Garden experts recommend three separate approaches (try them one at a time though – not all at once).

OIL BARRIER:  Add enough food-grade oil to create a slick on the water surface, which stops mosquitoes from releasing larvae. Any that get through won’t survive. A few tablespoons of vegetable oil is enough and won’t hurt your plants.

LARVICIDES:  Chemical and microbial control comes in granular or “dunk” form (available from most garden centers). The amount used is based on surface water area. We break each dunk, which looks like a sandy donut, into fourths and toss a piece in each barrel once a month.

FISH:  Some gardeners add a goldfish or a few guppies to each barrel. The fish will eat mosquito larvae as soon as they hit the water. But don’t combine fish with either of the other methods – the oil stops the water from being aerated so the fish will die.

To use more than one barrel side-by-side, raise adjacent units higher with extra blocks. With flexible tubing, divert water from the overflow of the highest barrel into the next lowest, and so on, creating a cascade. Depending on the diameter of the overflow on a single-barrel or the one closest to the ground, attach garden hose or other tubing to divert excess water away from the house.

multiple rain barrels

Multiple rain barrels linked together can capture hundreds of gallons of water from a good rain.

Remember, don’t mix and match mosquito control methods. Try one and use up the water before switching. And if you buy fish, check with the merchant. If the little swimmers do a great job, they may need supplemental fish food.

33 gallon rain barrels

This gardener in Ashland, Wisconsin, linked 5 33-gallon barrels together with PVC piping to capture water from one downspout. (Photo courtesy of the University of Wisconsin Ag Extension Service.)

For more information on rain barrels, go the The Environmental Blog  and the University of Wisconsin Ag Extension Services websites.

If you’re using rain barrels, we’d love to hear how yours are working!



14 Responses to Rain Barrel Basics: Prep, Placement, Pests

  1. Free2bme May 31, 2013 at 6:34 pm #

    I purchased a small submersible pump for my rain barrel so i can pump the water to gardens that are farther away. I got it at a pond store and it was inexpensive and allows me to use my rainwater without lugging it back and forth via buckets. I love my rain barrel but sometimes it gets kind of moldy — especially if I don’t use it that often. Do you know the best way to clean them? Mine is plastic. Thanks for this post!

  2. Your Easy Garden Team June 1, 2013 at 12:49 pm #

    Thanks for your tip. We use Simple Green to clean our barrel. It’s earth friendly, non-caustic, etc.

  3. j preach June 3, 2013 at 1:23 pm #

    When linking barrels together, connect the hose near the bottom of each barrel. That way you can keep them on the same level and they will act as one barrel (the water will fill all barrels at the same time and to the same level) rather than sequential filling, as pictured above.

  4. NLR June 8, 2013 at 1:25 am #

    We now have a 4 barrel stack of rain barrels behind our house and are trying to noodle thru the plumbing. Any reason to have more than a single tube from one to the next? Will the water pressure on the bottom tube be too great for a 3/4″ hose or pvc?

  5. Pamela Coyle June 8, 2013 at 2:43 pm #

    Noodling we understand! You should be fine. We secure the hose with a strap tie for a little extra insurance. Just make sure the last barrel has a good, long overflow hose or piping. During a big rain, even four barrels fill up quickly. Tweet with a photo to @youreasygarden on Twitter when you’re done. Thanks!

  6. Pamela Coyle June 8, 2013 at 2:46 pm #

    I’ve also used a small pump – a sump pump my husband rigged to charge with an old car battery and a solar charger. It does save time and wear-and-tear on the back for sure. Thanks for reading.

  7. Ann June 30, 2013 at 7:28 pm #

    I like the fish ithe barrel idea. Has anyone else tried it yet?

  8. Your Easy Garden Team July 1, 2013 at 1:53 pm #

    We’ve read articles about people doing it, but don’t have any first hand experience with it.

  9. carolee July 24, 2013 at 7:09 pm #

    My water from the rainbarrel smells like sulpher. What am I doing wrong?

  10. Pamela Coyle July 25, 2013 at 7:46 pm #

    Hi Carolee! Make sure the water going in passes through a fine screen to keep out as much residue as possible. Even then, pollen that washes off the roof will ferment and produce an odor after awhile. A dark screen will help control algae growth, which is another contributing factor. Other gardeners report good results from Barley Pond Clarifier, Algaecide and similar products used in ponds, though you won’t need as much. Finding a source of Efficient Microbes, also called Effective Microorganisms, or EMs, is another option. These are the little workers deployed to clean up pollution and spills in bodies of water. Here’s a good thread from Dave’s Garden that discusses the problem.

  11. Infidel!! August 11, 2013 at 4:01 pm #

    May I suggest you find an article dealing with “Aquaponics”. It is a way of growing a garden, a la Hydroponics…only with a twist. By placing fish in the water, along with your garden plants, the two will “feed each other”. The plants add much needed oxygen to the water for the fish, and the fish excrement adds fertilizer to the water for the plants. It’s a symbiotic relationship.

    Just food for thought 😉

  12. Ray October 25, 2013 at 2:40 am #

    I am getting acid barrels from my work for water storage. They held acid solution for dialysis. The acid solution is very weak. Filled barrels with water and a box of backing soda to neutralize any acid remaining and will bleach each. Do you think they are safe for water storage? Potable water? they are 55 gallon blue plastic.

  13. Pamela Coyle October 29, 2013 at 4:12 pm #

    I’d recommend filling one with water after you bleach it and rinse it out and testing the pH to gauge the acid level. Generally, anything other than barrels that contained food or food-grade materials should NOT be used for potable water storage, though storage for garden irrigation, washing clothes and dishes, etc., should be okay. Please keep in mind I am not a chemist – you don’t say what type of acid the barrels stored and that does make a difference. This thread may be helpful:

  14. Abby June 14, 2016 at 9:21 pm #

    Works great. But watch for overflow as they will float out during a storm. My youngest adopted last year’s rain barrel fish when I brought them in for the winter. So it is time to restock.

Leave a Reply