Weekly Express-News Article

By Calvin R. Finch, PhD, SAWS Water Resources Director, and Horticulturist

Saturday, June 28, 2008

“Drought Tactics – Drip Irrigation and Leaky Hoses”

            Hot weather and no rain up to now.  There are some predictions that we should get normal rainfall this month, but the same predictions were in play for May and June.  Plan for more drought.

 

            Gardeners need to be in a maintenance mode.  The goal is to help the plants we have survive the drought and heat.  It is too much to expect that you can improve or expand the plant part of your landscape during a severe drought situation.

 

            There are opportunities, however, to improve infrastructure of your landscape.

 

            Consider putting in a drip irrigation system on vegetables, flowers, and shrubs.  Drip systems irrigate plants at their base without spraying water into the air to have it evaporate or blow away.  Professionals will put a drip system in for you or you can do it yourself by using one of the many kits that are available.  A number of local nurseries sell drip irrigation supplies.  They will often help you lay out your plan and show you how to insert the emitters and make connections.  All systems also have plugs and other repair parts in case you make an error.

 

            I have an extensive system over two acres of plants and raised beds.  It includes a controller for turning the water applications for particular zones and self-cleaning emitters.  My system has been in place for six years, and despite claims from sprinkler advocates, none of the emitters have clogged from calcium build-up. 

 

            Like all irrigation systems, however, drip irrigation does require maintenance.  String mowers, heavy feet, pets, tillers, shovels, and even wildlife will break emitters or cause leaks.

 

            If constructing a regular drip system sounds like too much work or is not in the budget, you can have an instant drip system at a very low cost by a using leaky hose.  A leaky hose is the black, rough looking hose that is available in 25 – 100 feet rolls at your garden store.  Water leaks out over the entire length of the hose when it is placed in shrub borders or gardens.  Connect it to the spigot directly or at the end of a regular hose, turn the spigot one-quarter turn, and it is a very effective drip system.  You can even put an inexpensive timer on the hose.  For $25 - $75, you have an efficient drip irrigation system. 

 

            Remember, with a leaky hose the amount of water released is related to the water pressure.  The water should not gush, but only drip.  Resist the temptation to apply water at high pressure, instead, turn the spigot one-quarter to one half-turn and let it run on your plants for several hours.

 

            For shrubs and newly planted trees, water every one to two weeks with your drip system.  For your vegetables and flowers you may have to irrigate every two days.  In San Antonio, the drought restrictions are very liberal on the use of drip or leaky hose irrigation because they are so efficient.

 

            Be conservative about watering your lawn, over half the water used during the summer is for lawn watering in most communities.  Tolerate a lawn that is a little off color and do not water more than once/week.  When you water, apply enough water to fill the whole soil reservoir (about .75 inches in most cases).  For a good indication how much water your lawn needs to stay healthy, enroll in SAWS’ SIP Program.  Visit the SAWS website to sign up.  It is free, you receive free sprinkler measurement equipment, and every week you receive an e-mail telling you how much water your lawn needs based on grass type, sun exposure, and the week’s weather condition.  You do not have to be a SAWS’ customer or live in San Antonio to receive the service.  The Program has worked for ten years. 

 

            During a drought, do not forget the birds and the bees.  Place a bird bath or two out and keep them clean and full of water.  In many neighborhoods the bees are desperate for moisture.  They are so important for plants that gardeners should encourage them even if it means they dominate the bird bath or hummingbird feeders during part of the day.  The birds find times to get their share especially if you provide more than one source.