Many turfgrass yards, including mine, are feeling the effects of an extended droughty period this month. While one of the benefits of the primary turf species grown in the area (Centipedegrass, Zoysiagrass, Bermudagrass, and Bahiagrass), is their drought tolerant nature, they aren’t impervious to drought. Even with these tough grass species the difference between a yard coming out of a drought in decent shape versus dead is as simple as remembering the answers to the following four maintenance questions.
How much should I water to keep my grass alive?
Lawngrass needs about ¾-1” of water per week to remain looking its best and growing vigorously. Obviously, unless you have an irrigation system, keeping a large yard of turfgrass in that ideal water range is going to be hard or impossible. So, what to do? I encourage homeowners to focus their efforts on keeping grass around highly visible and often used areas of the yard well-watered, letting outlying areas fend for themselves until rain resumes. To ensure you’re putting out the optimal ¾-1” of irrigation per watering event, spread a few straight sided cans (tuna or cat food cans work great) under the sprinkler’s range, allow it to run until you reach the 1” mark, and note how long it took to apply that amount of water. This will help you dial in your watering and ensure water isn’t wasted.
Should I mow during a drought?
We all know that an unmown yard looks unkempt. However, given that mowing is a major stress on turfgrass, mowing during a drought can weaken your yard’s ability to recover when the drought ends. If you must mow to keep things looking neat, try to mow only areas that you keep watered and raise your mower’s deck to reduce the amount of leaf tissue you cut from the grass. Mowing in this manner will reduce stress on your turf and keep the yard from appearing weedy and unkempt. My unirrigated Centipedegrass yard has been flowering and setting seed over the last few weeks. My last mowing event (during the current dry period) was designed to only remove seedheads and minimize removal of leaf tissue.
Unirrigated Centipedegrass turf showing drought stress – photo courtesy of Daniel Leonard.
Should I fertilize?
This one is easy! Don’t fertilize grass during a drought! For one, fertilizer promotes growth, and grass isn’t trying to grow during a drought, simply survive. Fertilizing in these times is another unnecessary stress. Additionally, fertilizer requires water to transport nutrients down to the plant roots. If there is no water to do so, it will simply sit there and wait on rain. Also, some or all the nitrogen in the fertilizer applied will volatize and return to the atmosphere, wasting your time, money, and effort and stressing your turfgrass in the process. Hold the fertilizer until rain begins again.
What do I do about weeds?
Turfgrass isn’t the only thing stressed during droughts; weeds are as well. During stressful events like droughts, all plants (weeds included) stop growing and enter survival mode. This has major implications for weed control, as herbicides are not particularly effective on weeds with drought defenses up. In addition to being ineffective, herbicides can injure stressed turfgrass, preventing a healthy recovery post-drought. So, keep the herbicide off the yard until the weeds, and your turf, are happy and growing again.
Maintaining an unirrigated lawn during drought is more about what you don’t do – less mowing and no fertilizer or herbicide applications – than what you do. Mowing too low, applying fertilizer, and trying to control weeds with herbicide are all potential stressors of turf and can inhibit its recovery when the rain returns. The best you can do to keep your lawn healthy in dry times is to apply ¾-1” of water per week and pray for rain! For more information about lawn management or any other horticultural topic, contact your local UF/IFAS County Extension office.
Though the calendar says November, the weather in Northwest Florida is still producing summer or at least spring-like temperatures. The nice days are wonderful opportunities to accomplish many of those outside landscape chores. But, it is also a good time to start planning for next month’s colder temperatures. Since we don’t experience frozen soil, winter is the best time to transplant hardy trees and shrubs. Deciduous trees establish root systems more quickly while dormant; versus installing them in the spring with all their tender new leaves.
Remove an inch or more for extremely rootbound trees.
Here are a few suggestions for tasks that can be performed this month:
Plant shade trees, fruit trees, and evergreen shrubs.
Do major re-shaping of shade trees, if needed, during the winter dormancy.
Check houseplants for insect pests such as scale, mealy bugs, fungus gnats, whitefly and spider mites.
Continue to mulch leaves from the lawn. Shred excess leaves and add to planting beds or compost pile.
Replenish finished compost and mulch in planting beds, preferably before the first freeze.
Switch sprinkler systems to ‘Manual’ mode for the balance of winter.
Water thoroughly before a hard freeze to reduce plants’ chances of damage.
Water lawn and all other plants once every three weeks or so, if supplemental rainfall is less than one inch in a three week period.
Fertilize pansies and other winter annuals as needed.
Build protective coverings or moving devices for tender plants before the freeze warming.
Be sure to clean, sharpen and repair all your garden and lawn tools. Now is also the best time to clean and have your power mower, edger and trimmer serviced.
Be sure the mower blade is sharpened and balanced as well.
Provide food and water to the area’s wintering birds.
Mowing a lawn. Photo Credit: University of Florida/IFAS
So far, our fall has been unusually dry with warmer temperatures. Even though our average annual rainfall is around sixty-two inches per year, we don’t always receive rain exactly when we need it. There are times when we need to apply additional water. During dry weather, employ the following water management practices to improve the water efficiency of your lawn and landscape.
Mulching helps conserve water. On bare ground, about sixty percent of the water can be lost through evaporation. A two to three-inch layer of mulch will help hold onto the water so the plants can use it. Try to mulch the entire root zone when possible or at least apply mulch all the way around the plants out to the end of the branches.
Irrigate on as needed basis during dry periods. Credit: Larry Williams
When watering, a thorough soaking to wet the soil to a depth of six to eight inches is much better for plants than light, frequent watering. Three to five gallons of water applied to one spot under the canopy of trees or shrubs should thoroughly saturate the root zone in that location. During dry periods, as a general rule), twenty-five percent of the root system, when watered thoroughly, can absorb all the water a plant requires at any given time.
When watering lawns, apply one inch of water per week when we are not getting rain. Although many sprinklers have irrigation rates of ¼ inch per hour, some may apply up to one inch per hour. Measure your irrigation rate and uniformity by placing several open-top containers of the same size under the sprinkler and see how long it takes to apply a known amount of water such as ½ inch.
An efficient irrigation program on turf should not begin until the lawn grass shows signs of moisture stress. Symptoms include a dull and bluish-green color and leaf blades folding. The most efficient time to irrigate is between sunset and sunrise because of less evaporation, less wind and lower temperatures. Early morning is the next most effective time to irrigate while midday is the least efficient.
Avoid fertilizing drought-stressed plants. Fertilizers are chemical salts and will dehydrate roots when water is in short supply. If you need to apply a pesticide, make certain the plant is not wilted at the time and spray during early morning or late afternoon. You should also avoid unnecessary pruning of plants during drought. Pruning encourages new growth, which has a high demand for water.
On a recent family walk, I noticed something pretty obvious. One of our neighbors had a broken irrigation head. Luckily this is an easy fix, because a new rotor can just be screwed into place. But seeing the amount of water running into the street got me thinking about some additional ways to save water. Scroll down for some water saving tips based on the 9 Principles for Florida Friendly Landscaping.
Water runoff from a broken irrigation head. Photo Credit: Matt Lollar, University of Florida/IFAS Extension – Santa Rosa County
4 Ways to Save Water
Pick the right plant for the right place. Turf is an excellent choice for catching runoff in the situation pictured above. However, it’s important to evaluate your yard based on the amount of sunlight received throughout the day. Once you’ve determined if you need sun loving, shade loving, or plants that can handle a little of both, you’ll want to check how well your soil drains. Some plants can handle wet conditions better than others. Use the FFL Plant Guide to help pick the plants for your space.
Irrigate based on plant requirements. Plants like to be watered thoroughly to the extent of their rootzones. For turf, we recommend irrigating deeply and infrequently early in the morning. This method encourages the roots to grow deep to reach the water needed. Most established trees and shrubs don’t need supplemental irrigation unless we’re going through an extended period of drought. Review the Summary of Turf and Landscape Irrigation Recommendations to help determine the amount of water your yard needs.
Calibrate the irrigation system. If you have an irrigation system, then you need to make sure it’s calibrated. To do this, you’ll first need to make sure your system doesn’t have any leaks or broken heads and redirect heads to water plants instead of the driveway, sidewalk, or road. Next, you’ll need to determine how long to run your system based on water output. The run time test is detailed on the UF/IFAS Calibrating Your Irrigation System webpage.
Use mulch around trees and shrubs. Mulch can help hold moisture and conserve water. It’s important to keep mulch to between 2 and 3 inches deep and at least 2 inches away from the base of trees and shrubs. There’s a lot more information on Choosing and Installing Mulches on the Gardening Solutions website.
Following these simple tips will ensure that you’re watering efficiently and effectively. If you have additional questions about irrigation or just about anything plant related, please contact your local UF/IFAS Extension Office.
It amazes me that even under flood conditions, people still water their lawns.
I’m sure you’ve seen it too – we get enough rain to cause some areas to flood and yet you see irrigation systems going full blast.
Lawn irrigation should be applied on an as needed basis. Credit: Larry Williams
We should water our lawns, landscapes and gardens on an as-needed basis. The way that some people water their lawns is as logical as saying that a pet dog needs a drink of water at 4 p.m. everyday. This is not true. When watering, we are simply replacing water that is lost. This is true when we drink water ourselves, when we provide water for a pet dog, or when we provide water for our lawns, landscapes and gardens.
An irrigation system is a great tool when used to supplement rainfall. Irrigating too much not only wastes water but it also is the cause for many lawn problems such as shallow, weak root systems, leaching of fertilizer and numerous lawn diseases. Cutting the irrigation timer to off and operating the system manually will solve many lawn problems.
Also, there are tools to prevent an irrigation system from coming on during rain or when adequate rainfall has occurred. As a matter of fact, it has been state law in Florida for every automatic irrigation system to have a rain shutoff device installed since 1991.
Florida Statutes, Chapter 373.62 – Water conservation; automatic sprinkler systems states, “Any person who purchases and installs an automatic lawn sprinkler system after May 1, 1991, shall install a rain sensor device or switch which will override the irrigation cycle of the sprinkler system when adequate rainfall has occurred,”
Rain sensors are available, inexpensive and are not difficult to install. Rain shutoff devices really do work when installed properly. If you do not feel qualified to install such a devise on an existing system, check with a reputable irrigation company.
Water only when lawn indicates that water is needed. When the grass needs water, leaf blades fold along the midrib – like a book closing, footprints remain in the lawn long after being made and the lawn turns grayish in spots, indicating it needs water.
When 30 to 40 percent of the lawn shows these signs of water need, turn the irrigation system on and let it run long enough to apply one-half to three-quarters inch of water. Don’t water again until the lawn begins to show these signs of water need. Watering this way will develop a deep-rooted lawn and landscape. Here’s a UF/IFAS Extension link with more information on lawn and landscape irrigation. https://gardeningsolutions.ifas.ufl.edu/care/irrigation
As the weather warms up, people will be outside tending to their landscapes more often. Part of that tending involves a simple thing that everyone knows plants need: water. And that is correct! Plants DO need water, and most of them need it regularly. However, even with the sandy soils in our area that drain quickly, it is possible to overwater your plants!
Overwatering can cause patchy dieback of shrubs and trees.
It is not uncommon to have a dry spell in the spring or fall in North Florida. Weeks may pass by with little or no rain, until the summer rains settle in. People may set their irrigation systems to deal with the lack of rain, but then forget to change the settings once the water isn’t needed. When plants receive too much water, we see a number of things happen. Trees and shrubs may appear to be deficient of nutrients, displaying yellowed leaves. They may die back and have a patchy appearance. Sprinklers that run constantly and splash water on leaves may increase the number of fungal diseases that plants get. Lawns that stay too damp may start seeing moisture-loving weeds such as dollarweed pop up in profusion. Luckily, we do have some guidelines for how much we should water.
For lawns or landscape plants, it is important to know what plants you are dealing with. Different plants have different needs when it comes to irrigation. Plants should be grouped by their water (and light) needs in a landscape, and irrigation zones should be set with those groupings in mind. Plants that enjoy or tolerate more water include wax myrtle, yaupon holly, swamp sunflower, swamp milkweed, pond cypress, and river birch. Others enjoy drier and well-drained soils, such as yucca, oleander, false rosemary, and turkey oak. To help determine the cultural needs of various plants, try consulting the Florida Friendly Landscaping Guide to Plant Selection and Landscape Design or the Florida Native Plant Society’s website.
When deciding whether or not to irrigate, one thing to pay attention to is the weather. All too often sprinkler systems will continue to run despite the weather – even in the middle of a thunderstorm! Install a rainfall shutoff device or make sure yours is functioning properly to avoid this. Overwatering can lead to unhealthy plants, disease issues, and weed problems.
Improperly placed or calibrated sprinklers can lead to lawn problems!
It can help to learn what a thirsty lawn looks like. Turfgrass that needs a drink will fold up its leaves, become dull bluish-green in color, and footprints will remain instead of the grass springing back. When signs of drought stress are evident, it’s time to water.
How much to water? The recommended amount is ½ to ¾ inch of water per application. Different irrigation emitters put out different amounts of water over time, so some measurement is necessary. Put out some small, straight-sided cans such as tuna or cat food cans in the area to be measured, run the irrigation for 15 minutes, and then measure how deep the water is in the cans. If you’ve collected ¼ inch of water in that time, you’ll know that you need to run the system for 30-45 minutes to give your lawn a thorough watering.
For more watering tips, there is plenty of information available. Check out these links:
