After waiting your turn for the shower, you finally get your chance. You turn on the water, adjust the temperature, and step under the warm spray… which suddenly turns freezing cold as the hot water heater runs out of water. Yikes!
We don’t enjoy a sudden dousing of icy water. Neither do our plants. They may not look startled (how does a bean plant look startled?), but the cold water abruptly chills the soil and slows their growth. Since our growing season here in Colorado is often too short to begin wth, pouring cold water on our plants is to be avoided.
My garden water comes from a 200-foot deep well, and it certainly qualifies as frigid. I didn’t want to irrigate with water that cold, so we cobbled together a simple way to warm it up a bit before it flows onto the plants.
Our drip system has the usual array of valves that deliver water to an assortment of watering zones. The valves are fed by a pipe that also connects to the closest faucet. We purchased a 100-foot length of thick black plastic tubing from our local big-box home improvement store. Then it was a simple matter insert that tubing between that source pipe and the valves. We scattered the coils of tubing off to the side, outside the garden. (I have plenty of space, but in a tight situation, you could run it along a fence or near-by roof.) The whole set-up is similar to the solar collectors used for heating water in swimming pools.
If you don’t have a fixed irrigation system, you could create a similar set-up by inserting a long length of sun-warmed hose between your faucet and your sprinkler or hose-end sprayer.
In the fifteen years we’ve had this system in place, we’ve had three problems. One is that the water gets too hot! Surprisingly, this is rare, as the pipes feeding my soaker hoses are underground. The warmed water running through them is cooled off again before it reaches the plants. Unless we’re swealtering during a heat wave, the water comes out pleasantly warm.
Letting the weeds grow up to partially shade the hose solved this problem. Another solution would be to mix the warmed water with cold, as we do in a household faucet.
In years with plenty of rainfall, the tubing gets completely buried in weeds. Attacking the area with a string-trimmer (taking care to avoid harming the tubing) solves that problem.
And finally, the hose developed a crack one year, and we had to remove the damaged section, joining the two ends back together with a hose repair kit.
While I don’t have detailed statistics, my observation has been that my seeds germinate faster crops and my crops mature earlier with the warmed water, compared to the years I irrigated with water straight from the well.