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
Now that we are moving into warmer soil temperatures, weak areas in lawns will have a better chance of making some recovery. However, this is highly dependent on whether or not correct lawn maintenance practices are followed. These practices include fertilizing, mowing and watering correctly.
Warmer soil and correct care help improve weak lawns
Many North Florida lawns came out of winter weak and thinning this spring. In areas of the lawn where there is at least sixty percent cover of the desirable type of lawn grass, recovery is possible. But where there is less than sixty percent desirable cover, reestablishment should be considered.
Applying the correct type and amount of fertilizer will promote lawn recovery. To maintain a healthy Florida lawn, it’s critical to use a fertilizer with adequate potassium. In most cases, use a lawn fertilizer with equal amounts of nitrogen (first number) and potassium (third number) such as 8-0-8, 10-0-10, 15-2-15 or similar analysis. Phosphorus (second number) should be low or zero unless you have the results of a reliable soil test indicating that more phosphorus is needed. Err on the side of being light handed when applying fertilizer to the lawn. In North Florida, most lawns will do just fine with an application in spring no earlier than mid-April and a second application in summer no later than mid-September.
Follow these mowing practices for a healthy lawn.
Never remove more than 1/3 of the leaf blade height at any one time.
Here’s the recommended mowing height in inches for each lawn grass: bahia – 3 to 4; centipede – 1.5 to 2; standard St. Augustine cultivars – 3 to 4; dwarf St. Augustine cultivars (Captiva and Seville) – 2 to 3; zoysia cultivars suitable for home lawns- 2 to 2.5; bermuda – .5 to 1.5.
Keep mower blades sharp.
Follow these irrigation practices for a deeper rooted and drought tolerant lawn.
Turn your automatic sprinkler system off and learn to operate it manually on an as-needed basis. Your lawn needs water when leaf blades start to fold in half lengthwise or when footprints remain visible in the lawn long after being made. Irrigate when at least 30% of the lawn shows these signs of water need.
Apply ½ – ¾ inch of water when you do irrigate. Place empty, straight-sided cans in the area being irrigated to see how long it takes to reach this amount.
Irrigate during early morning for more efficient water use and to minimize lawn diseases.
Here is a link to a UF/IFAS Extension publication on Best Management Practices for a Florida lawn. http://edis.ifas.ufl.edu/ep236
Do you have a low-growing weed that is producing tufts of white, fluffy, dandelion-like seeds, which float in the wind when disturbed or mowed? This is Annual Trampweed (Facelis retusa). I did not see this weed in North Florida until recent years. It’s native to South America.
Mid-April to early May is the time of year when this winter annual weed goes to seed in North Florida. That’s what it is doing now and it is a prolific seed producer. Each white tuft contains numerous seeds. Each tiny seed is attached to a small individual bristle, coming out of the larger tuft, which is carried by wind. This allows hundreds of seeds to move to other locations.
Trampweed is approaching the end of its life as we move into early May. As a winter annual, the individual weed dies in response to warm temperatures only to leave behind hundreds of seeds that survive the summer. These same seeds come up the following fall to early winter to begin the next generation. The best time to attempt chemical control with an herbicide is well before these weeds mature and begin flowering.
Trampweed in bloom. Credit: Larry Williams
One chemical control option is to apply a lawn preemergence herbicide during October when nighttime temperatures drop to 55° to 60°F for several consecutive nights. This will be just before these winter annual weeds emerge. Done correctly, the application of a preemergence herbicide forms a temporary chemical barrier along the soil surface preventing the winter annual weeds from emerging. Hence the name preemergence.
A second application of preemergence herbicide may be required six to nine weeks after the initial application to achieve season-long control, based on the product’s label directions.
If you miss this narrow window of opportunity to apply a preemergence herbicide, watch for the small young weeds in winter and treat then with a postemergence herbicide that is labelled for use in the type of lawn grass you are growing.
Waiting until trampweed is producing flowers and seeds in April and May to attempt control is almost worthless in controlling this weed. Correct timing is critical.
Trampweed usually is found in areas of a lawn that are already weak and thinning. It favors open, dry, stressed and low-fertility areas of a lawn. So, try to manage your lawn correctly. This involves learning to mow, irrigate and fertilize correctly for the type of lawn grass you are growing.
As a boy I remember our St. Augustinegrass lawn. I fondly remember winter annual weeds in that lawn.
Many of these so called “weeds” are native wildflowers. And a number of pollinators use these wildflowers.
To see clumps of winter annuals in our yard and in neighbors’ yards was a natural part of the transition from winter to spring. They added interest to the lawn. It was expected to see henbit with its square stiff stems holding up a display of small pinkish purple flowers in late winter to early spring. A clump of henbit was a great place to hide an Easter egg, especially a pink or purple one.
A pink Easter egg hidden in a mix of clover. Photo Credit: Larry Williams, UF/IFAS Extension – Okaloosa County
Wild geranium offered another good hiding place for eggs with its pink to purple flowers. Large clumps of annual chickweed would nicely hide whole eggs. Green colored eggs would blend with chickweed’s green leaves.
Crimson clover with its reddish flowers, hop clover and black medic with their bright yellow flowers provided good hiding places for Easter eggs. Plus, clovers add nitrogen back to our soils.
A yellow Easter egg hidden in a mix of clover. Photo Credit: Larry Williams, UF/IFAS Extension – Okaloosa County
The lawn was healthy and thick enough to limit summer weeds. But during fall and winter, as the lawn would naturally thin and go dormant, these winter annuals would run their course.
I remember the clean smell of freshly mowed grass in spring with the first mowing. Once mowed and as the heat took its toll, by late April or mid-May, these winter annuals were gone. What was left was a green lawn to help cool the landscape as the weather warmed. The lawn was mowed high as St. Augustine should be, watered only occasionally during dry periods, played on and typically not worried with.
Most lawns have winter annuals that let us know spring is near. Perhaps we worry too much with these seasonal, temporary plants that may have wrongly been labeled as weeds. Besides, how long have we been doing battle with them and they are still here. Most lawns have winter annual seeds that await the cooler temperatures and shorter days of early winter to begin yet another generation. By May they are gone.
UF/IFAS Extension agents in the Florida Panhandle are asking you to join in on “No Mow March” in 2023. The idea is to holdup on mowing until the calendar flips to April, allowing pollinators to enjoy these common winter annuals.
Here is a website with more information on No Mow March. On this site, you’ll find a link to sign up to be a participant, check out what Okaloosa and other counties are doing by clicking on “Events” and see more about pollinators, all on this site.
There are important landscape lessons to learn from recent, early and widespread freezes.
First, know the average climate for the region you live in here in Florida. The work has already been done for you with the USDA Plant Hardiness Zone Map. Here is a link for the map: https://planthardiness.ars.usda.gov. Find your zone on the map. Note that Northwest Florida includes zones 8a, 8b and 9a.
The newest map, with interactive features, was updated in 2012.
This map is based on the average annual minimum winter temperature and is divided into 10°F zones. It can help you determine which plants are most likely to thrive in your zone. There are areas bordering Alabama, located in the extreme northern portions of Escambia, Santa Rosa, Okaloosa, Walton and Holmes Counties, that are in Zone 8a, with an average annual extreme minimum temperature of 10 to 15 degrees F. Most of these counties fall within zone 8b, with an average annual extreme minimum temperature of 15 to 20 degrees F. The extreme southern portions of these same counties (bordering the Gulf) are in Zone 9a with an average annual extreme minimum temperature of 20 to 25 degrees F. As you go south in Florida, you move into Zones 9b, 10a, 10b, and 11a. Zone 10b has an average annual extreme minimum temperature of 35 to 40 degrees F. Zone 11a; which includes a small portion of West Palm Beach and Fort Lauderdale, most of Miami and all of the Florida Keys; has an average annual extreme minimum temperature of 40 to 45 degrees F.
Most of the Panhandle is in USDA Hardiness zone 8b.
It seems that some people move to extreme north Florida and think they are in extreme south Florida. They move barely below Alabama or Georgia and want to plant the palms, citrus and tropical plants that thrive in extreme south Florida. If you live in Zone 9a, perhaps you might get by with growing a few plants that are well suited for 9b. But it is wise to mostly grow plants that are known to flourish in the Plant Hardiness Zone where you live.
Secondly, follow principle one, which is Right Plant, Right Place, as explained in the UF/IFAS Extension Florida-Friendly Landscape™ (FFL) Program. Following this principle results in developing a healthy, low-maintenance landscape by using Florida-Friendly plants that match your site’s soil, light, water and climatic conditions and that require limited supplemental irrigation, potentially less fertilizer and fewer pesticides.
More information on the FFL Program is available through this UF/IFAS Extension link (https://ffl.ifas.ufl.edu) or from the Extension Office in your County.
Using these tools may be a great goal for 2023 as we replace cold-injured plants.
