Lately there have been quite a few articles and stories talking about the over consumption of water in turfgrass. As many of us know parts of California have put strict demands on water usage and one of their main targets are home lawns. Over the past few years we have seen everything from districts paying home owners to take out grass, to people putting in artificial synthetic lawns.   What we’re not seeing is a lot of information about how you can have a lawn and also conserve water. How do you know if you’re using water wisely? Today’s blog is all about tips for saving water and what you should be doing as a homeowner, landscaper, or golf course to help protect our natural resources.

Water loss is determined by a term called evapotranspiration (ET). You may be familiar with this term but for those that aren’t a brief definition is water lost to the atmosphere through evaporation or from transpiration of a particular plant. Water is lost through the transpiration or sweating or the plant and also through evaporation from the soil surface. Most cities publish the daily ET rates in the weather section on their website or newspaper. This number will tell you how much water the plant can hold to bring the soil up to field capacity. This number DOES NOT tell you how much water is absolutely necessary to keep the plant alive. Just like the human body a plant or in this case grass can handle a certain amount of stress and adapt well to the conditions. While we often feel better after we eat a meal our bodies wouldn’t operate efficiently if we tried to maintain the feeling of being full all day. Grass is the same way, and it needs stress in order to adapt to the environment.  A typical lawn needs to be watered once every two to three days during the summer months.  You should be replacing 70-80% of ET when you water.

I want to start with the basics and work our way up to a couple additional ways you can save water and money throughout the year. While most people have an automatic sprinkler system there is still a large portion of homeowners that set out a sprinkler and move it around their yard. Not only is this way inefficient, it is also extremely difficult to give your turf the correct amount of water. We all know that setting a timer and going out and moving a sprinkler around the yard is going to produce less than stellar results but what many don’t realize is how much water they’re wasting.

First it is unlikely that most people will be up a couple hours before sunrise to water at the optimal time of the day. It is optimal to water two to three hours before sunrise. This will allow your lawn to use water efficiently and will also reduce loss to evaporation. Every afternoon when I leave work I see sprinklers running at homes during the hottest part of the day. Most people assume that the grass needs water in order to survive the hot afternoon sun, but I don’t think they realize a large portion of the water is lost to evaporation. It is simply too hot during the day to expect water to fully seep into the grass plant and work its way down to the root system. Watering before sunrise reduces several environmental factors that play a key role in water loss. Water is lost through heat, wind, over saturation, and through the air. Setting your clock to water early in the morning is your first tip to a large water savings.

Now that you have your clock set to water at the correct time you need to determine the output of your sprinklers. If you take nothing else away from this blog I recommend you do this test. Get several small cans (tuna sized cans work well) and place them sporadically throughout your yard. These should be positioned to check the output of your individual sprinklers. Run the irrigation system for 10-15 minutes and check the cans to see how much water has been collected. You will probably notice that some cans have very little water and others may too much. This test determines the efficiency of your sprinkler system and by now you’re probably realizing why some areas of your lawn look better than others. If you have cans that have very little water in them then you need to look at your sprinkler spacing, nozzle type, or see if there is something preventing the correct flow. One item that is a big hindrance to flow is when your grass is taller than your pop up sprinkler. You always want to make sure your sprinklers are clear and nothing is in the way of them.

After you have tidied up your irrigation system and have consistent outputs you want to measure how much water is collected. As I said earlier you only need to water your lawn every two to three days but how much water do you need? A typical warm season turf should be watered to a 6-10 inch depth every time you water. This can be checked by inserting a screwdriver into the soil after you water. If it only gores down 4 inches you know you need to water longer. When you’re watering you should apply ¾” of water to make sure you get enough water down to the roots. Any less than this amount will cause your lawn to have shallow roots and will weaken the grass. A typical pop up sprinkler has the output of .3-.4 inches of water every 15 minutes. So in order to get ¾” you would need to apply around 30 minutes of water per zone. Most lawns cannot tolerate 30 straight minutes of water without causing runoff so you would want to set up a cycle/soak program. On your clock you will set it up to run at 4:00am for 15 minutes on zone 1 and at 4:15 it will run for 15 minutes on zone 2. You will then setup zone 1 to run again at 4:30 and zone 2 at 4:45 for 15 minutes. This allows you to put down the desired amount of water and gives your lawn time to soak down to the roots. Remember deep and infrequent is much better for your lawn than daily watering. Daily watering is the worst thing you can do for your lawns health. I always say if you watered a tree everyday it wouldn’t have any root system and eventually it would fall over. The same is true for grass, shallow roots equate to quick plant desiccation.

I understand that few people will take the time to look at what the daily ET is so how do you know how long to water if you don’t know the ET? There are some obvious signs that the turfgrass plant will go through to let you know that it is time to water. Here are a few things to look for before setting up your clock to run.

1. Blueish/grey tint to the leaf blade. This is a sign of stress but by no means does it indicate you will lose grass.
2. Walk across your lawn and see if your footprints don’t bounce back. A dry lawn will show footprints everywhere that you walked.

Just like there are some obvious symptoms of a dry lawn, there are also some clear indicators of a lawn that has been overwatered.

1. You see puddles all over your lawn for several minutes after you water. This is also an indication that you should aerify your lawn and open up the pore space.
2. When you walk across your lawn and it feels soggy it is way too wet.
3. Lawns that are continually overwatered will start to sprout mushrooms in the wetter areas.

Overwatering your lawn is just as detrimental as under watering your lawn so be careful and pay attention. I’m going to finish today with some bullet points on what every homeowner can do to reduce the amount of water they use.

• Check your sprinklers while they’re running and make sure you’re only watering the lawn. Sprinklers that are watering the driveway or sidewalks need to be adjusted to the proper angles.
• Aerate your lawn to allow for better water infiltration and root growth.
• If you reduce the amount of fertilizer you use it has a direct correlation with the amount of water you use. You can still have a green lawn without excessive nitrogen. Iron can be applied to keep lawns green during stress periods.
• Water 2-3 hours before sunrise to reduce environmental factors
• Check your valve boxes and lawn for leaks. A leaky valve will use more water in a day than running your sprinklers for 30 minutes.
• Set up a rain sensor to allow your clock to shut off when you have adequate rainfall.

Everything I listed above is a quick fix to a rather large problem. The entire southwest has been in drought conditions for several years but if everyone took a few minutes to water correctly we could make a dramatic difference. Turf is often viewed as the big bad water waster but let me leave you with a few reasons why you should put a lawn in.

Sod creates a healthy environment. Sod cleans the air and helps recharge our groundwater supplies. Turfgrass is one of nature’s finest and least expensive filters, and works to improve the environment.

Sod reduces heat, glare, and noise. On a hot summer day, a lawn will be 30 degrees cooler than asphalt & 15 degrees cooler than bare soil. The front lawns of 8 homes have the cooling effect in hot weather of about 70 tons of air conditioning.

As always I’m here to take your questions. Now get out there and check your sprinkler systems.

Jay

PS…. Be sure to check out the San Francisco 49ers when they debut at the new Levi’s Stadium in Santa Clara.  We installed our water saving Bandera Bermuda on the field.  It is a spectacular facility and we’re proud to be a part of it!