How to calibrate your irrigation system

Calibrating or determining the rate of water your sprinkler system applies is an easy job.

Here’s how to do it:

  1. Obtain 5 to 10 straight-sided empty cans such as tuna fish or soup cans.
  2. Place the containers randomly within the irrigated area so that they catch the water when the irrigation system is running. This needs to be done for each irrigation zone, separately.
  3. Turn the water on for 15 minutes.
  4. Use a ruler to measure the depth of water in each can. The more exact your measurement, the better your calibration will be. Measurements to the nearest 1/8 inch are adequate.
  5. Determine the average depth of water collected in the cans (add up the depths of water measured in each can and then divide by the number of cans).
  6. To determine the irrigation rate in inches per hour, multiply the average depth of water times four. For example, if you collected an average of ¼ inch of water in the cans as a result of letting the irrigation run for 15 minutes, the irrigation zone would need to run for 30 minutes to apply ½ inch of water, or 45 minutes to apply ¾ inch of water, etc.

It’s best to do this calibration exercise during the same time of day the system normally runs so that water pressures are similar.

Here’s why calibrating your system is important.

When a timer/controller is set to come on frequently for short intervals of time (every other day for 20 minutes for example), the result will be a shallow, weak root system and a lawn that becomes dependent on its shallow roots being watered frequently. Also, watering frequently benefits certain weeds such as dollarweed and nutsedge while weakening the lawn.

To develop a deep, strong root system and a lawn that will go through hot, dry weather in better shape without requiring water as often, switch the automatic timer to manual.

Watering a lawn on an as-needed basis is the best way to water correctly and develop a deep-rooted lawn. This is the reason for calibrating your irrigation system. You should apply ½ to ¾ inch of water to the lawn only when the grass indicates that water is needed. When the grass needs water, the leaf blades fold along the midrib (like a book closing). Also, footprints or tire tracks remain on 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 ½ to ¾ inch of water. Don’t water again until the lawn begins to show these signs of water need. Don’t water when adequate rain has occurred.

The best time to observe these signs of water need is during the evening when the grass is not in full sun or under heat stress. It’s best to irrigate during early morning hours to prevent lawn diseases and to minimize water loss due to wind and evaporation. The lawn grass is a great indicator for when most other established plants in a landscape need water, as well. Larry Williams, UF/IFAS Extension Office

Join CoCoRaHS and Collect Rainfall Totals for Local Weather Forecasting

Are you a weather watcher? Interested in citizen science? Here’s a potential program you may be interested in.

The local Community Collaborative Rain, Hail, and Snow network is seeking interested citizen scientists to participate in the collecting weather data. See the notice below from local coordinator, Larry McDonald, for more information:

Weather forecasting depends on taking readings and measurements from the atmosphere. And it’s not just professionals, like meteorologists, who measure rainfall, temperatures, and humidity levels. You can, too! The Community Collaborative Rain, Hail, and Snow network (CoCoRaHS) allows everyday citizens to participate in weather data collection by measuring daily precipitation/rainfall totals at their own homes or workplaces. Using a special rain gauge that provides great detail in detecting rain amounts, CoCoRaHS observers submit rain observations online to a national network… along with over 20,000 participants in the U.S., Canada, and the Bahamas. Precipitation amounts are then evaluated for many needs by national, regional, and local weather forecasters, researchers, drought and flood monitoring, and agricultural interests. Rainfall data submitted can also be used in forecasting to predict the possibility of flash flooding for local flood prone areas.

A CoCoRaHS observer simply needs to purchase the approved rain gauge (costing from $30 to $40), mount the gauge in an open area away from roofs, fences, and vegetation, and simply collect rain that falls directly from the sky over a 24-hour period. Once each day, between 5:30 AM and 9:00 AM, the gauge is checked for rain with the amount recorded and submitted to the CoCoRaHS website. Missing a day or more is okay, but the more you report, the better the overall data becomes for your area. New and active CoCoRaHS observers are needed throughout Escambia and Santa Rosa Counties.

Those interested in possibly joining CoCoRaHS as an observer can obtain more information by visiting You can also contact the CoCoRaHS local volunteer coordinator for Escambia and Santa Rosa Counties by emailing

Steps to solve plant problems may include a visit to the plant clinic

Diagnosing landscape problems can be tricky. There are basic steps that can be useful in solving plant problems in your landscape.

Step 1 Identify the Plant. By knowing the type of plant affected, you can begin relating causes to symptoms you see on the plants.

Step 2 Survey the site. Is the problem occurring to one plant or a group of plants? Is it a local problem in your landscape only, or are the other plants of the same type throughout the neighborhood showing the same problem? What has been the recent weather pattern? Is the soil well-drained or wet and boggy? Is there an open drain spout near the plant?

Step 3 Ask questions. Has there been anything unusual spilled or applied within the vicinity? Was fertilizer recently applied, how much, what kind? Has the plant been sprayed with pesticide?

Step 4 Examine the plant thoroughly. Look closely at the foliage. A magnifying glass is useful in detecting pests like spider mites and lacewing bugs. Flower thrips and mites can be seen by shaking a flower over a piece of white paper. Are leaves showing a tip burn or scorching (usually caused by environmental stress)? Are there distinct spots on the foliage (indicating a possible disease)? Do roots appear dark and decayed (likely fungus or too wet soil), stuffy (potential nematode problem), or white and healthy?3 Ask questions. Has there been anything unusual spilled or applied within the vicinity? Was fertilizer recently applied, how much, what kind? Has the plant been sprayed with pesticide? 

After careful inspection of the plant and site, collect and bring samples to our next Plant Clinic if you’re still stumped.

The March plant clinic will be held Friday, March 25, from 9 a.m. to noon in Fort Walton Beach at the Okaloosa Farmers’ Market located at 1954 Lewis Turner Boulevard close to the Northwest Florida Fairgrounds. It will be in the open-covered pavilion. 

The plant clinic is designed to provide a place and time for people to bring in samples of plants for diagnosis, including weeds for identification. 

If you have a plant problem that you would like diagnosed, bring a sample of the weed, plant, insect, etc., to the clinic. Be sure to get a fresh sample representing what is seen in the landscape. Examples may include a plant stem with several leaves, a 4-inch square of grass with roots attached, etc. 

You may also bring a sample of your soil for pH testing.  Larry Williams, UF/IFAS Extension Agent

Grow bananas out in the yard

You may not be thinking about growing bananas during the colder winter months, but we can have some success with this tropical fruit in North Florida.

Banana plants are tropical and, as such, they add a tropical look to the landscape. They usually require 12-18 months to produce a flower stalk. And the fruit takes four to eight months to mature, depending on the temperature during the growing season.

When winters are mild in North Florida or when the plants are protected, the stalk may survive the winter and produce fruit in the second year. The tops are usually killed by freezing temperatures when winters are cold, so no fruit is produced.

Some gardeners grow banana plants by potting them in large containers and carrying the plants into a protected area such as a greenhouse or garage during the winter. Others may build an insulating wrap of pine straw around the trunk, enabling the plant to survive outdoors during the winter. The key is protecting the trunk and roots during freezing temperatures. If the stalk freezes, there usually will be no fruit production the following year. 

Producing good fruit requires plenty of water and fertilizer. Adjust soil pH to 5.5 to 6.5 before planting. Mulching is beneficial in conserving water, reducing weeds, and protecting the rhizomes (underground stems) from winter freezes. Water regularly and deeply during the summer if rainfall is poor. If the soil is extremely wet, root rot may develop. In low fertility, sandy soils fertilize 4 to 6 times during the growing season (late spring through summer) with a 3:1:6 ratio fertilizer such as 6-1-12 fertilizer or similar analysis. 

Bananas should be pruned. In the beginning, let only one main stalk develop from each rhizome. After six months, allow a replacement sucker to grow because the main stalk is removed after fruiting. You can use unneeded suckers to establish new plants. The rhizomes may be dug up and divided to propagate more plants. 

Cavendish is probably the banana variety best adapted to North Florida. The plant grows about seven feet tall, produces good quality fruit, and is slightly more cold-hardy than most other types. 

Be aware that there are ornamental types of banana plants grown just as landscape plants. These types produce small fruit, full of hard, large seeds, and usually are not edible. 

More information on growing bananas is available at or through the UF/IFAS Extension Office in your County. 

Larry Williams, UF/IFAS Extension Agent

Getting ready for another lawn growing season presentation

Correcting four common mistakes can result in a better lawn. 

The first step in correctly managing a Florida lawn is to know the type of grass you’re managing. The kind of lawn pests, mowing height, herbicide selection, irrigation requirements, and fertilization and lime needs depend on the type of lawn grass. Many local lawns decline or die entirely due to being maintained improperly… all because the person managing the lawn doesn’t know the requirements for the lawn grass being managed. 

Most homeowners do not know the size of their lawn. As a result, most people apply too much fertilizer and pesticides. Lawn fertilizers, insecticides, herbicides, and fungicides are applied based on square feet (lawn area). Directions on these products instruct to mix and or apply a certain amount per 1000 square feet of lawn area. Most homeowners apply too much of these chemicals due to not knowing the size of their lawns. Overdosing a lawn with fertilizers and pesticides results in a lawn costing more than it should. Plus, it’s unwise and illegal to apply pesticides at a higher rate than the label directions. And, applying too much fertilizer and weed killer (herbicide) can injure a lawn. Overuse of insecticides and herbicides can result in pest resistance. This can result in a population of pest insects and weeds that no longer can be controlled with currently available insecticides and herbicides. 

Many home lawns are irrigated incorrectly. Watering correctly involves applying ½ to ¾ inch of water on an as-needed basis to meet the lawn’s needs. To do this, the lawn manager needs to know the number of minutes to let the watering system run to provide this amount of water and the visual signs of when the lawn is indicating that additional water is needed. This is referred to as calibrating an irrigation system.  

Many homeowners mow their lawns too low. This is a common cause for lawns becoming weak and thin. Weeds then move in where the lawn is thin. 

On Wednesday, March 16, I’ll provide a seminar titled Getting Ready for Another Lawn Growing Season. This hour-long presentation begins at 10 a.m. and will be held at the Okaloosa County Extension Office at 3098 Airport Road in Crestview. During this presentation, I will show how to prevent/correct these common mistakes. Doing so can result in a better lawn that requires fewer inputs, time, and money.   

Please register for this free seminar using this link. Space is limited.

For additional info or assistance, call (850) 689-5850. 

Larry Williams, UF/IFAS Extension Agent

Be careful when topdressing lawns

Routinely applying a layer of soil or sand to a lawn can cause more damage than good. This practice is sometimes referred to as topdressing. You can introduce weed seeds, nematodes, and even diseases with some sources of lawn dressing. The main reasons to apply a layer of soil or sand to a lawn are to fill in low or bare areas as a method of dealing with an identified thatch problem or possibly to cover surface tree roots.

Topdressing your lawn with sand on a regular basis is not a recommended practice.
Topdressing soil should be free of weeds and nematodes and should be of the same soil type (texture) as the turf is currently growing.

While minor low spots can be corrected this way, you can easily overdo it and smother your lawn. Using topsoil from an unknown source may introduce undesirable plants and weeds into the landscape, creating additional work and expense to correct the problem.

It can be difficult to spread the sand in a timely manner evenly. Homeowners start with the best intentions of spreading the sand consistently and finishing by the end of the day, only to find that the job is slow and difficult. The sandpile remains in the same spot for days, or longer, shading out and frequently killing the grass below. Once the initial enthusiasm wanes, just trying to reduce the mountain of sand overcomes the objective of spreading it consistently and evenly over the lawn. The result is dozens of small mounds of sand all over the yard.

Shovel the sand, no more than about an inch or two in-depth, into the area to fill a low spot. It’s best to maintain the lawn normally until the grass has grown on top of the first layer. Repeat until the low area is filled.

Homeowners are sometimes convinced that topdressing will improve the condition of their lawn by increasing the spread and thickness of their turf.

“Topdressing home lawns has minimal agronomic benefits,” according to Dr. Bryan Unruh, University of Florida Extension Turfgrass Specialist. When asked his advice for homeowners on topdressing, his reply was “don’t.”
On Wednesday, March 16, I’ll provide a seminar “Getting Ready for Another Lawn Growing Season.” This hour-long presentation begins at 10 a.m. and will be held at the Okaloosa County Extension Office at 3098 Airport Road in Crestview. During this presentation, I will cover four common lawn mistakes. Correcting these mistakes can result in a better lawn that requires fewer inputs, time, and money.
Please register for this free seminar using this link. Space is limited.
For additional info or assistance, call (850) 689-5850.

Larry Williams, UF/IFAS Extension Agent

Don’t react too quickly to cold-injured plants

Our winter temperatures go back and forth all season here in North Florida – one week it’s winter, the next week we may think spring has arrived. This back and forth with cold and mild temperatures throughout winter is typical in North Florida.

As a result of the freezing periods, the less cold-hardy tropical and subtropical landscape plants can be injured. For example, it’s normal for popular landscape plants such as oleander, hibiscus, bottlebrush, and philodendron to suffer some cold damage. Then, the first impulse for many gardeners is to cut away the dead and dying leaves and branches. But, this really is not the best idea.

During winter, it’s difficult to tell how much damage has been done to these plants. If you prune immediately after a freeze, you probably will cut away live wood that does not have to be lost. Also, cold damaged leaves and branches on the outer part of the plant can help protect the rest of the plant when the next freeze strikes.

Some of the more tender landscape plants such as banana, cassia, ginger, tropical hibiscus and many of the tropical perennials may have been severely injured with the first freeze. But, don’t give up on them too soon. These plants may surprise you by sending up new shoots come spring. Some of these plants require warm soil temperatures before they’ll produce new growth. Many of the gingers, for example, may not show any sign of life until April or May of 2022.

Some winter and spring flowering plants such as camellia and azalea may experience flower bud damage. This will be evident at blooming times when these plants have few to no flowers. Cold injured camellia flower buds will either drop off the plant or only partially open showing brown centers. Stem damage will show up in spring and early summer when some of the branches begin to die. Cold injured leaves will fall as new spring growth occurs.

Individual stems on some cold-sensitive plants such as azalea and bottlebrush may split or crack during a freeze. Some of these injured branches will begin to die during spring and summer.

February and early March can bring occasional frosts and freezes. It’s not unusual to have our last killing frost toward the middle of March or even in early April in parts of North Florida.

When “spring really has sprung,” you’ll know what survived and what did not. This will be after new growth occurs and after the danger of another frost or freeze has passed. That’s the time prune. Larry Williams, UF/IFAS Extension Agent

Caring for the plants you brought in for winter

Winter is probably the easiest time of year to kill the plant you brought in from the cold. And, the fastest way is by overwatering. Grueling growing conditions like lower light levels, dry air, shorter days, and chilly temperatures really stress plants, making them susceptible to insect and disease problems. Then the pests finish them off.

The secret to helping plants survive winter is adjusting care routines to suit seasonal growing conditions. Here are a few things to consider.


In winter, the sun is lower in the sky, and light levels near windows drop up to 50 percent. Houseplants that grow near a sunny eastern or northern window in summer may need a southern or western exposure in winter. Likewise, tropical plants that were able to withstand direct sun outside will need to be in the brightest spots possible or require extra lighting inside. Plants are likely to lose leaves to adjust to the light change. The new leaves that grow back will be accustomed to the lower light. Remember that if those plants are going back outside in the spring. They will need to be shaded for a while, or the new leaves will sunburn.

To help plants cope with changing light levels:

  • Move plants closer to windows, if possible.
  • Clean windows to allow maximum light transmission.
  • Shift plants to new locations near brighter windows for winter.
  • Wash dust off plants so leaves can make maximum use of available light.
  • Add artificial light. Fluorescent bulbs provide adequate light. They’re cheaper than traditional grow lights and produce less heat. Position bulbs 4 to 12 inches away from plants for effective results.


Most of these plants prefer temperatures between 65° F and 75° F during the day and about 10 -15 degrees cooler at night. For tropical plants, temperatures below 50° F can cause problems. Hopefully, you had the chance to bring them in with the first cool spell a month ago.

Adjust thermostats for your comfort, but remember your plants need some consideration.

  • Avoid placing plants near cold drafts or heat sources.
  • Keep plants several inches away from exterior windows.


Homes may offer only 5-10 percent relative humidity in winter. Houseplants like 40-50 percent. Signs of low humidity stress on plants include brown leaf tips and the appearance of pests like spider mites.

  • Raise humidity around plants with a room humidifier.
  • Place plants on a pebble-lined tray filled with water. Keep the water level just below the pebbles. As the water evaporates, it raises humidity around plants.
  • Mist plants with room-temperature water. Avoid wetting walls or furniture.


The most common problem plants suffer from in winter is overwatering. Most plants need soil to dry out almost completely before watering. How can you tell if plants need water?

  • Don’t just spot test the soil surface. Plants need water when the root zone is dry. Poke your finger into soil up to 2 inches. If the soil is dry, water.
  • Lift the pot. Soil is lighter when it’s dry. Learn how wet soil feels by lifting pots immediately after watering.
  • Exceptions to drying out between watering: Potted citrus and ferns require consistently moist soil. Always research plant moisture needs if you’re unsure.

Never allow plants to sit overnight in water that collects in the drainage saucer when you do water.

Fertilizer, Pruning and Repotting

Save these tasks until spring. Winter growth is usually leggy. Prune and fertilize to encourage bushy growth when the sunlight and temperatures increase. The right time to repot most tropical houseplants is during periods of active growth – in spring and summer. The exception is potted woody plants that go completely dormant in winter. Transplant those before bud break in early spring.

Sheila Dunning, Commercial Horticulture Agent III

Flowering Cherries and Plums for Spring

There are few trees as showy in bloom as flowering cherries and plums. Covered in pink or white flowers, these trees are often the first to bloom and signal that spring is near. Many species of flowering cherries are widely used in northern areas but most are not well adapted to North Florida. However, there are a few flowering cherries and plums that can tolerate this region’s heat and humidity.

The best flowering cherries and plums for our area are shared below by Dr. Gary Knox, Horticulture Specialist with UF/IFAS.

Taiwan Cherry (Prunus campanulata) is the best pink flowering cherry for our area. Native to China, Taiwan Cherry grows as a slender tree up to 25 feet tall. It produces carmine-rose flowers in late winter. Flowers can be showy for 3 weeks if freezes don’t damage them.

‘Okame’ Cherry (Prunus x incamp ‘Okame’) is a hybrid between Taiwan Cherry and Fuji Cherry. It has bright pink flowers about a week later than Taiwan Cherry. ‘Okame’ Cherry grows about 25 feet tall but is somewhat wider than Taiwan Cherry.

Chickasaw Plum (Prunus angustifolia) is a native small tree growing up to 20 feet tall. It often spreads to form thickets. White flowers appear in early spring along its thorny branches. The native American Plum (Prunus americana) is similar but may be found as a single-stemmed tree growing up to 25 feet tall. Flatwoods Plum (Prunus umbellata) is a native, round-topped tree up to 20 feet in height. It has a spectacular display of small, white flower clusters in late February. Fruits of all three species are prized by wildlife.

Northern types of flowering cherries are sometimes sold here but are not well adapted and should be avoided. These include Japanese Flowering Cherry (Prunus serrulata and its cultivar, ‘Kwanzan’), Higan Cherry (P. subhirtella), Cherry Plum (P. cerasifera; usually in the form of their purple-leaved cultivars), and Yoshino Cherry (P. x yedoensis).

As a group, flowering cherries and plums are considered short-lived, typically just 15 to 20 years.

Flowering cherries and tree-form flowering plums are best used as a specimen tree. The shrubby, thicket-forming flowering plums are effective in a shrub border or naturalized area.

The flowering cherries and plums for our area are best adapted to sunny to partially shaded sites with moist but well-drained soil. Flowering cherries and plums are susceptible to many pests, including borers, aphids, tent caterpillars, scale, as well as a host of fungal diseases. Proper placement in the landscape and irrigation during drought will help forestall pests and prolong tree life. Plant them away from lawn areas so that their trunks are never exposed to damage from mowing equipment.

Larry Williams, UF/IFAS Extension Agent

New Year Resolution: Compost for a More Productive Garden

Much of the trash that we throw away can be used to make our gardens more productive. A great New Year’s resolution is to begin to covert yard and kitchen debris into soil-enriching compost.

Many materials can be used to produce compost. Grass clippings, leaves, eggshells, coffee grounds, tea bags, vegetable and fruit clippings, shredded paper, and chopped brush are a few examples of organic matter suitable for composting. Cheese, meat scraps, fats, or bones should be avoided as they may attract pests like rodents. Also, these materials are slower to decompose and may create an odor problem.

The size of a compost bin may vary but the enclosure needs to be at least 3 feet by 3 feet by 3 feet. It can be made from almost anything: wire, wooden pallets, or cement blocks. One side should be either open or removable for ease of adding and removing materials from the bin.

A simple compost container is a wire hoop made from welded fence wire. The piece of fence wire should be long enough to make a 3-foot diameter hoop. This hoop bin is sturdy enough to stand upright on its own with no additional support.

The below link to the UF/IFAS Extension publication Compost Tips for the Home Gardener states, “To create the compost pile, layer roughly equal amounts of “green” materials and “brown” materials in alternating 3- to 4-inch tiers up to a height of about 3 feet. Smaller particles will decompose faster than larger materials. It is essential that each layer be watered as you build the pile; otherwise, it is almost impossible to moisten the center of the pile once it is completed. The materials should be moist, not soggy. There is no advantage to purchasing a compost “starter,” since organic yard wastes naturally contain the microorganisms needed to start the decomposition process.”

Examples of “green” materials are fresh lawn grass clippings and vegetable scraps. Examples of ‘brown” materials are dry fall tree leaves and small tree and shrub twigs.

Frequent turning of the compost materials with a shovel or pitchfork will benefit the bacteria and fungi, resulting in faster decomposition of the organic materials. When using the wire hoop method, simply pick up the wire hoop and set it to the side of the pile of compost. Next, use a pitchfork or shovel to place the compost materials back into the wire hoop in its new location.

Adopt composting for a more productive garden in 2022.

More information on composting is available at or through the UF/IFAS Extension Office in your County. Larry Williams, UF/IFAS Extension Agent