Our Arizona heat is finally here! With the rising temperatures our landscapes, particularly our plants, are beginning to show the stress of being under our Arizona sun each day. To cool themselves they begin to use up their reserves of stored energy; the food in and around the roots. The hotter it is, the more energy they need to cool themselves. Making energy for a plant requires water; and although water is required, it is timely water that matters most to them. Watering too late in the afternoon will likely only waste water as the plants have already went into conservation mode, beginning to shut down the very systems they use internally to get water. The best time to water plants, especially if there are symptoms of heat stress (droopy or dry leaves), is the early morning hours as the sun comes up. This is the time when the plants are the hungriest for both water and nutrients. Giving them water at this time allows the plant to uptake the water it needs to help build the energy it uses to face the intensity of our Arizona sun!
Armed with a little more about how our plants work, a simple adjustment to the irrigation timing can lead our landscapes to not only be beautiful, they can also use water more wisely.