You can significantly reduce your outdoor water use with a desert-adapted landscape. Drought-tolerant plants and trees require less maintenance and water than lawns, especially when irrigated correctly. However, if you have grass or are thinking of installing some - natural or artificial - it's vital to have all the facts to ensure you make the right decision. After all, practical water-wise changes in our desert climate will positively impact your community's water future.
What is Functional Grass?
Functional grass is actively used as a recreation space for people and pets and is often found in backyards, side yards, and HOA common areas. These areas tend to be flat with straight edges, making it easy to irrigate and limiting water waste. Functional grass is easily accessible, usually by a sidewalk or pathway.
Functional grass areas are sometimes used for stormwater retention purposes. For more information about retention basins, contact your city's Planning Department.
What is Non-Functional Grass?
If your grass serves no practical purpose and is difficult to water, it is probably non-functional. Those areas tend to be ornamental or for looks only and are typically found in front yards, along streets, or entrances to HOAs. Non-functional grass areas have lots of curves and unique angles, which makes it hard to irrigate efficiently with standard irrigation equipment, which causes runoff. Overspray or runoff can lead to paint, wall, asphalt, or other infrastructure damage.
How Much Functional Grass Space is Acceptable?
There is not a precise amount that is recommended; however, most people find that about 1,000 square feet of functional grass area is enough to satisfy their needs.
How Much Water Will You Save?
Did you know that majority of water use occurs outdoors in your yard? Converting to a xeriscape can save 50% or more on outdoor water use. A Bermuda or Bermuda hybrid lawn requires more than 55 inches of water per year (with winter overseed) and over 40 inches per year (without winter overseed). The average xeriscape requires less than 18 inches per year. Compare that with our average rainfall of eight inches, and you will have a better idea of precisely how much water your grass requires.
Before You Start, Have a Good Plan
Creating a plan will ensure you create a landscape that meets your needs, tastes, and budget. It will also keep you from making costly mistakes. If you require some help in planning your new landscape, visit your city's conservation page for helpful tips, free resources like workshops and classes, and rebates.
Ideas for Updating Your Landscape
If your entire yard is currently grass, you can treat your space as a blank slate and walk through the Landscaping with Style guide to design a new functional yard.
Often, grass does not fill an entire yard, and it can be overwhelming to try and come up with easy options for updating different parts of your yard. Here are some ideas to consider and to get your imagination flowing:
- If the grass you are removing has a hardscape border, you don't necessarily have to get rid of the border. You can remove your grass, fill in the area with unique accent plants, such as agave, and add contrasting decomposed granite (either in size or color) for a modern look.
- Convert your grass area into a patio with pavers.
- If there are multiple bordered areas in your yard, convert the most non-functional areas to xeriscape while keeping the functional, most-used grass areas.
- Reduce your grass area's total size and adjust the area's shape. Limiting curves and slopes will make your grass easier to irrigate. This will save water and increase efficiency.
- Select your irrigation equipment for your functional grass area first. Then, match the dimensions of your grass area to the recommended specifications of the irrigation equipment.
- Just like appropriate grass areas, artificial turf may be a good option for applications under 1,000 square feet.
- Looking out a window to see green is always nice, so consider planting desert-friendly plants or vines instead. Outdoor artwork, like ornamental doors and metal work, is also a great choice that is hassle-free.
Getting Rid of Grass
Bermudagrass is aggressive. Therefore, it can be challenging to get rid of, which is why it does so well in our desert climate. After months of being brown and looking like it is too far gone, bermudagrass can spring back to life when water is applied. The most effective way to eradicate it for good is by carefully using a proper herbicide.
What to use:
Using herbicides with glyphosate is the most effective way of killing bermudagrass. Glyphosate is a systemic herbicide that is absorbed through the leaves and travels to the roots to eliminate grass as it actively grows. It is commonly sold under many brand names, so check the label before buying and, more importantly, before using it. Since glyphosate doesn't affect soil - trees, shrubs, and flowers can still be planted safely; just avoid spraying chemicals on their green leaves. Otherwise, choose the appropriate herbicide for your grass and weeds. You may need to use a selective herbicide if the grass grows close to your desirable plants.
Remember, bermudagrass is invasive and persistent, even in our desert climate. Other methods such as solarizing, vinegar sprays, smothering, digging out, tilling, or sod cutters may be more complex and have a lower success rate. Some of these methods may be more effective when used together.
Additional tips for removing grass:
- Turning off the water to your lawn is not a good way to kill the grass. Bermuda lawns can have very deep root systems, which can continue to live for years on rain alone.
- Covering the grass with black plastic and granite is not recommended as a method to kill or control the grass. The plastic eventually breaks down and tears, leaving the landscape unsightly and difficult to clean.
- Do not use a soil sterilizer or complete vegetation killer, as these chemicals can travel through the soil and kill other plants in your yard.
- If you choose to use an herbicide, add a water-soluble colorant so you can detect where you have already sprayed. Walk backward while applying herbicide to avoid tracking to unintended areas.
Before determining if synthetic turf is the right choice for your yard, consider the following other factors:
- Will kids and pets play on the artificial turf? There are safety concerns with artificial turf, which is often too hot for children and pets to play on, reaching over 150 degrees Fahrenheit during the day (ASU).
Artificial turf does not behave the same way as living grass. It does not return to its upright position after activities. Therefore, it requires infill to be added between the blades to help them spring back. Different types of infill have various benefits and tradeoffs; however, adequate risk assessments have not been performed to assess their safety for children and pets. Exposure to chemicals in artificial turf infill may pose potential health risks to humans and animals.
- How much maintenance are you willing to perform? Artificial turf is not maintenance-free. It must be brushed and rinsed off with water (and sometimes soap) to keep the area clean and avoid staining. Additionally, you need to regularly remove debris, like leaves and pet waste, to prevent mold buildup or other containments. You will also need to pull weeds from the surrounding areas because they can invade your artificial turf landscape. Artificial turf doesn't allow water to permeate, creating runoff/pooling concerns, so be especially mindful if the area has a slope or is next to a pool.
- What will go on the artificial turf? Patio furniture with sharp legs can puncture and damage artificial turf. Keep grills, fire pits, fireworks, and other combustible heat sources far from your artificial turf, as embers can also cause serious damage.
- Do you have living plants in the same yard? Artificial turf has artificial components that can negatively impact your soil quality, making it difficult for living plants to thrive in the surrounding areas of your yard. In addition, the heat from the surface of the artificial turf affects the air temperature and can create microclimates that some plants may not tolerate.
- What is the longevity of your investment? Artificial turf does not last forever. Different products have different lifespans, but regardless of your chosen product, it will eventually need to be replaced because plastic does not hold up well under the Arizona sun. When the time comes, you will also need to consider how and where you dispose of your artificial turf.
When to Water:
Water at night or during the cool morning hours to minimize evaporation. The peak water consumption hours (4 - 9 pm) and the peak evapotranspiration hours should be avoided.
How Often to Water:
An established ryegrass lawn should be watered about once a week during the winter and every three days during the spring. The time between irrigations will depend on the weather, grass, and soil type. Water lawns no more than once every three days during the summer.
How Much to Water:
Plant watering needs vary from month to month. Regularly adjusting your irrigation schedule is an easy way to save water and money and helps ensure your plants get the right amount of water to thrive.
Consult Water—Use It Wisely's step-by-step, interactive watering guides for a deeper dive into how much and how often to water your lawn and plants.
- If water runs off your yard, irrigate more often but for shorter periods to avoid water waste.
- Install sprinkler heads vertically and flush with the soil surface. Make sure grass is not blocking the spray.
- Adjust sprinkler heads, so they don't spray walls, driveways, or sidewalks.
- Hand water dry areas rather than increasing overall watering time.
- Replace broken and missing sprinklers immediately.
- Consult an irrigation supplier for information about the most efficient types of sprinklers and irrigation control clocks.
- Water shaded areas about 30% less than sunny areas.
- If it has rained, reduce watering accordingly.
- Don't set it and forget it! Text WHENTOWATER to 33222 to receive a text from AMWUA on the first of each month with a link to the month's watering guidelines.
Signs of Under-Watering
- Bermudagrass turns bluish-grey and doesn't spring back after you step on it.
- The soil is too hard to push a screwdriver into it.
- Areas of the grass still feel warm in the evening after the sun has gone down
Signs of Over-Watering
- Water is constantly puddling in areas.
- The turf has a musty odor.
- The soil is extremely soft or mushy.
- Moss, Dichondra, or mushrooms are present.
Proper mowing is essential for maintaining a healthy lawn. Avoid scalping your lawn because grass that is too short uses more water. Adjust your mower so the grass height is maintained within the ranges listed below:
Grass Height (inches)
1 ½ - 2
½ - 1
1 ½ - 2
1 ½ - 2
1 ½ - 3
2 ½ - 3 ½
Mowing Schedule During Peak Growing Season
Grass Height (inches)
2 - 3
4 - 5
7 - 10
12 - 18
- Don't remove more than one-third of the grass at a time. If you can't frequently mow, increase your mowing height.
- Keep mower blades sharp.
- You shouldn't need to bag your clippings if you mow frequently and do not over-water or over-fertilize, except for some bermudagrass hybrids.
- Avoid following the same pattern each time you mow.
- Increase the mowing height by 25% in shady areas.
- Use a reel-type mower when mowing grass at the height of one inch or less.
Thatch is a mat of plant material consisting mainly of grass stems and roots. A thin layer is good because it acts as mulch, which reduces evaporation. Too much thatch will repel water, cause shallow roots, and make the grass less resistant to drought.
Excessive thatch is usually caused by over-watering or over-fertilizing. If thatch is over one-half inch, it should be removed with a vertical mower or a power rake. Both are available from equipment rental companies.
Regular fertilizing is essential for proper growth and good color during the growing season. However, an over-fertilized lawn will require more water and more frequent mowing. Follow the fertilizer directions carefully - more is not necessarily better.
If there are no directions on the package, look for the nutrient analysis. The three numbers represent the percentages of nitrogen (N), phosphorus (P), and potassium (K) in the formula. Some plants need phosphorous and potassium, but these nutrients seldom affect established lawns in Arizona.
An excellent general rule is to apply ½ lb. of nitrogen per 1,000 square feet each month between April and September for bermudagrass lawns. Apply ½ - ¾ lb. per month to established ryegrass lawns. Avoid fertilizing ryegrass in late spring and early summer.
- Avoid applying nitrogen fertilizer at the end of the growing season.
- Use "slow-release" fertilizers. Although they cost more, they release nutrients more efficiently and can be applied less frequently.
- Fertilize in the evening or early morning, then water the lawn thoroughly.
- For a more even application, apply half of the recommended amount in one direction and the other half in the opposite direction.
- Iron helps keep grass green during the late summer and fall. Use formulas with ferrous sulfate or iron chelates. Caution: It will stain concrete.
- Use a complete fertilizer and follow the directions on the package.
- If you are using an applicator and are unsure about which setting to use, pick a low one and make several passes until the required amount is applied.
Hard, compacted soil inhibits root growth and can cause puddling or runoff. Aerating your soil will help relieve these problems. Core aerating, a process where soil plugs are pulled out of the ground, helps air and water penetrate the soil. The best time to aerate bermudagrass is in May or June when the grass grows quickly. Make sure to aerate the day after an irrigation or rainfall when the ground is softer. While manually operated aerators are adequate for small lawns, mechanical ones are available at equipment rental companies for larger areas.
WEED, DISEASE, AND INSECT CONTROL:
A lawn that is not maintained or appropriately watered may be more susceptible to weeds, diseases, and pests. Contact your local nursery or the Maricopa County Cooperative Extension if your lawn shows signs of stress. They can help you identify the problem and offer advice.
You can also visit the University of Arizona's Turfgrass Research, Education, and Extension Office website for additional resources.