
Houston Zoo Horticulture Team Member
Efficient, intelligent watering is one of the most important factors in gardening. Rain is, of course, the most effective method of providing water and normally, we receive close to the perfect amount here in Houston. This year we haven’t seen near enough rain. When it comes to providing additional water to your plants, there are a number of things to consider. The most important thing is to provide less frequent, deep watering. This promotes healthy root and plant growth and ensures that the plant doesn’t stay saturated.
We always want to ensure that we aren’t wasting water either, there is only so much available. Currently there may not even be enough water, anybody that is dealing with water restrictions will agree. Sidewalks don’t need to be watered; those of us that have irrigation it’s important that we make sure that all of our sprinkler heads are hitting the correct areas. This also goes for when we are watering from a hose as well; shut-off valves are effective and easy to use. It isn’t necessary to water your porch when you are watering your potted plants. There are a number of watering wands available also, which have diffuser heads that provide a soft shower of water rather than a jet or stream of water. When the water pressure is too high, the soil doesn’t take in the water as readily and we displace the soil, which impacts the roots and root hairs limiting the plants ability to take in nutrients and water.
The most effective time to water is during the early morning hours. When we water during the heat of the day, most water is lost to evaporation and some plants can actually get burnt. When we water late at night the plants may not be taking in water as readily and there is the possibility of the plants sitting in water, providing opportunity for infection or damage. This being said, any time that you see a plant needs water, water it. If a plant dies, there is no amount of care that you can do to bring it back. Irrigation with a clock timer is a great way to make certain that you are watering at the proper time and that you don’t accidentally leave the water on wasting vast quantities of water. There is always going to be a degree of adjustment, both initially and seasonally, but irrigation on a clock eliminates a number of problem areas. Also those of you that have irrigation, will be having irrigation installed or that use a hose and are interested, adding a dechlorinator of some type will be very beneficial. The chlorine and chloramines in our water wreak havoc with the beneficial micro-organisms in our soils, but we will discuss soils a little later.
There are number of other things I can discuss about irrigation and hand watering, but I could go on forever. There is no cut and dry water plan that will be effect for everyone. Each plant requires different amounts of water, even virtually identical plants. We need to observe the conditions in our gardens. There’s a pretty big difference between a wilted and an over-watered plant. Check your soil. If the soil feels like it is damp, it probably doesn’t need water. If it feels dry, then it probably needs water. If when you water the water just runs off, you may need water a little, let the water absorb and then come back later, when the ground is ready to receive water.
Hopefully this is effective information. We’ve kept our 55 acres here at the zoo, with 12 horticulturists pretty well watered using them. Next time, I’ll be discussing soils and how healthy soils can help in keeping our plants watered and happy.
Article written by: Joe Williams, Manager of Horticulture at the Houston Zoo