Anyone who has gardened during the recent periods of drought will know how thankful one feels to have a ready, free source of water. Three cheers for the rain barrel! But what happens when you turn the tap and nothing comes out?

This happened to three of my four rain barrels late last summer, when I needed the water most. Were they clogged up with something so small it got through the mesh filter over the hole the downspout empties water into? Were the spigots rusted inside?

What many gardeners, including myself, didn't know or fully appreciate when we acquired our rain barrels is that they need to be emptied and cleaned out at least once a year. Around Thanksgiving is the perfect time to do it, before the outdoor temperature falls below freezing and stays there consistently. Over and above the issue of gunk inside, if you don't empty the barrel, the water in it may freeze and crack it.

Draining and cleaning a rain barrel falls into my category of easier said than done. A full 55-gallon barrel can weigh 450 pounds. How do you get the thing off its pedestal, and onto its side, then drain it and clean out the inside, which may have a thick layer of gunk on the bottom and algae along the sides?

When I say gunk, think the sand-like granules that flake off old shingles, bird poo, dead insect parts, etc., all small enough to have fallen through the screen. If the stuff has clogged up the barrel so badly that no water comes out when you turn the tap, you may need help removing the barrel, then you can lay it on its side and drain the water out. But if even a little water comes out, you can drain the barrel where it sits, then move it.

As for scrubbing the thing out, you'll need a long brush and a mixture of something non-toxic, such as vinegar and water, to clean it. If you use vinegar, be sure not to dump it out on grass or plants, because vinegar can kill vegetation.

An important point I can't emphasize enough: If you're thinking of buying an extra rain barrel, or your first one, make sure to get one with a lid the same width as the body of the barrel. On this type, the lid can be unscrewed, turned upside down, replaced on top of the barrel and used as a planter. This sort of barrel will be infinitely easier to clean out than one which has only a small opening at the top.

Unfortunately, three of my barrels fall into the second category. I'll probably need a flashlight to see what the inside looks like, once I've unscrewed the little filter on top, then a very long brush and a lot of elbow grease. YouTube is bound to be a big help when embarking on the chore.

Another red flag: When shopping for a rain barrel, don't be seduced by the beautiful, wooden wine barrels that have been converted to collect rain water. I have one that weighs a ton, even when empty. And it has one of those small openings at the top. If only I had known when I paid a stupid amount of money for it. Needless to say, I've never tried to clean it out.

If you want a rain barrel to stay in working order, a host of other things need to be done, too. Check for sediment, leaves, pine needles and moss in the filter screen on top, as well as in the tap and the overflow pipe. Keep your gutters and downspouts free of debris. Check that the screen has no holes in it and that it's securely fastened to the barrel so mosquitoes can't get inside and breed.

In spring, summer and fall, make sure to use the rain barrel water for your plants (but don't ever drink it) and avoid leaving water sitting in the barrel for long periods of time. If you plan to be away from home for a long period, leave the spigot open and make sure that the water will drain away from the foundations of your house.

Once you've scrubbed out your barrel and rinsed it, repaired any cracks and, if necessary, replaced the filter, store the barrel upside down in a sheltered spot. The barrel can be reconnected to a downspout around April 1.

In the meantime, happy gardening!

Editor's Note: Laetitia Sands is a master gardener in Dorchester County.