Rainwater Harvesting

With all the rain we’ve been blessed with lately, it’s hard to remember there’s much of a need for conserving water. But in a place like Austin that tends to get only 33 inches of annual rainfall – and all on 3 days as the old joke goes – finding creative ways to keep your garden moist can be tricky. Rain barrels and downspout-based rainwater-harvesting systems have become popular in Austin in part thanks to city subsidies or rebates for the purchase of those systems. I personally don’t have any kind of barrel-based system yet, as the basic cost has always been a little on the high side for us. And for people who don’t have a gutter system on their roof, a barrel or larger cistern won’t do much good.

Still, there are more ways to maximize the use of rain that falls on your property. Without a gutter or working downspout, you may still have a corner or low spot in your roof where rainwater might run off more than in other places. Buckets or cans of some sort can be used to collect rain for watering houseplants or plants that are sheltered outside by a porch or eaves.

Another technique that can be employed when designing landscape features is incorporating channels and low spots in your beds and yard. This is the central idea behind a rain garden. The basic idea is to move rainwater from paces it isn’t that useful to your landscape – the edges of your house, for instance, to places where it is useful. Since most modern yards were built by the developer to do one thing – move water away from the construction and off the property – reworking your landscape could seem like a big challenge.

But it doesn’t have to be. A simple low spot will allow water to collect and soak into the ground, ideally over a day or two. You can build elaborate channels to move water (re-routing elements of your sprinkler system as you do), like I’ve done, or simply dig a spot and allow rain to collect in it.

Besides drought, mosquitoes are probably one of a gardener’s least favorite things, and the tendency for us as maintainers of yards is to make sure we have no standing water around. Creating a rain garden might seem like it would add to the mosquito population, but in general, it won’t. Mosquitoes take about a week to utilize a new water source, but the goal of your rain garden should be to allow the water to soak in in under three days.

Another technique I’ve seen used in gardens is to place small, shallow dishes out, like glass pie dishes or the clay dishes from below potted plants. I have several martini glasses leftover from a party that I arranged in different places.  While this won’t benefit plants much, it does provide critical water for birds and wildlife, and is a valid method of providing water if applying for the National Wildlife Foundation’s Certified Wildlife Habitat status. And on a dry Texas days, the water will evaporate faster than mosquitoes can use it.