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:
Florida is rapidly urbanizing with 1,000 people a day moving into the state. Many cities in the panhandle have experienced accelerated growth rates over the past ten years. Crestview is one of the seven areas in the state with a population growth of 19% or greater, and the only one located in the panhandle. The 2030 predictions for Florida are another 6 million people, with counties containing military personnel increasing the quickest.
All of these people need water to meet their daily living needs. The average person in the United States uses 101.5 gallons of water per day. Residential water use comprises 61% of the public supply category. This category is responsible for the largest single portion (43%) of groundwater withdrawal in Florida. The Floridan aquifer spans an area of about 100,000 square miles in the southeastern United States, including all of Florida, as well as, portions of three other states. At the current statewide population growth rate, Florida is facing a 300 million gallon per day shortfall of future water needs, possibly as early as 2030.
Turfgrass is a key landscape component and often the most commonly used single type of plant in the residential landscape. However, on a hot, sunny day in midsummer, the average lawn uses 125 gallons of water per 1,000 square feet. Although Florida has a humid climate where the precipitation rate, on average, is greater than the evapotranspiration rate, the low water-holding capacity of the soil makes irrigation necessary for the high quality landscapes desired by homeowners. But, watering the yard requires an entire household to skip a shower, not wash anything and avoid cleaning. Or, we need to find ways to use a different source of water for irrigation and conserve the potable water for the people.
While the use of reclaimed water for landscape plants has become a standard in many parts of Florida, it has limited availability in the panhandle. However, there are many ways to reduce and conserve potable water use for those with in-ground irrigation systems. First, make sure you have a functional rain shut-off device. By design it will prevent the system from running when it has recently rained. On average, the panhandle has received rain about every 4 days this year. Besides, Florida law requires a rain shut-off device for all irrigation systems, new or old.
Then, calibrate each zone to determine the length of time required to deliver ½ inch of water. This can be determined by placing 10 or more, short, straight-sided containers throughout the irrigation zone. Run the system and look at each container, measuring the depth with a ruler. Adjust the run time so the system only delivers ½ inch. Now set the clock to run 2-3 times a week for that length of time. It’s that simple. And the water savings is significant. For these and many other irrigation tips, visit askIFAS at https://edis.ifas.ufl.edu/.
Mosquitoes are a pesky nuisance we’re all too familiar with, especially as we move into the summer months. Their presence can certainly make being outdoors undesirable. Not only are they a blood-sucking nuisance but they also carry and can transmit many diseases to humans. Mosquito-borne diseases of public health concern in Florida include St. Louis encephalitis, eastern equine encephalitis, West Nile virus encephalitis, dengue, and Zika. While it can be difficult to eliminate mosquito populations completely, there are steps we can all take to protect ourselves and to prevent our landscape from becoming a major breeding ground for mosquitos.
Asian Tiger Mosquito. Photo Credit: James Newman. UF/IFAS Photo.
Source Reduction
One way to keep mosquito populations down is to prevent the landscape from being a breeding ground for them. Many species of mosquitoes require standing water to lay their eggs; therefore, eliminating standing water can help keep populations low. Mosquitoes can develop in a variety of water-holding containers such as flowerpots, birdbaths, pet dishes, tree holes, bamboo trunks, and many others. It is important to:
Drain water from garbage cans, gutters, buckets, coolers, or any other containers where water is collected
Discard any old tires, bottles, broken appliances, or items not being used that could potentially hold water
Change water in birdbaths and/or outdoor pet dishes once or twice a week
Mosquito larvae. UF/IFAS File Photo
For areas such as ornamental ponds or water gardens, aeration or stocking them with mosquitofish (Gambusia species) can also help to keep mosquito populations down. The small fish will feed on the mosquito larvae and add movement to the water. They are most effective in small ponds with no other fish present.
For other areas with standing water that cannot be drained, such as rain barrels or ornamental ponds, products containing Bacillus thuringiensisisraelensis (Bti) are effective in controlling mosquito larvae. Products containing Bti come in the form of granules or “dunks”, which look like miniature donuts. These Bti products are considered a form of biological control as it is a naturally occurring bacteria that is specific to mosquito, blackfly, and fungus gnat larvae. Therefore, Bti products are not harmful to fish, waterfowl, pets or humans when used according to label directions.
Protective Clothing and Repellents
The most effective way to protect yourself from mosquito bites is to avoid infested areas, wear protective clothing, and wear insect repellent when outdoors. There are several repellents that are currently available such as DEET, picaridin, and IR3535, or plant derived chemicals such as citronella and oil of lemon eucalyptus.
It is important to read the label before applying mosquito repellent and to remember that there are different recommendations for frequency of application for different products. Below is a table comparison of products based upon University of Florida research.
Potting soil, potting mix, garden soil, topsoil. The bags are all sitting side-by-side on the shelf at the garden center. Your challenge is to figure out which one you need for your project. What’s the difference? To begin with, none of them are dirt. The Soil Science Society of America defines dirt as “displaced soil”, the dead nuisance material left on your hands after working with soil. Soil is a blend of sand, silt, clay and organic matter. It is alive with nutrient and water holding components. But, all soil is not equal.
Soil contains decayed organic remains. It may be composted leaf tissue and/or microorganisms. The terms potting soil and potting mix are often used interchangeably, but there is a significant difference. Potting soil contains compost or the flora responsible for the breakdown process. Potting mix is soil-less. It is a blend of sphagnum moss, coir, bark, perlite and/or vermiculite. While these are natural occurring materials, they are in their original state. No decomposition has occurred. In the absence of compost, the resulting potting mix is sterile and free of fungus spores and insect eggs. Potting mixes are excellent choices for container growing, especially for house plants. The sphagnum moss, coir and bark hold and release water and nutrients, while the vermiculite or perlite keep the mix loose and well-drained. Some blended products add microbes, which then requires the word soil be added to the packaging. These are still suitable for potted plants.
But, if the potting soil is made from mostly compost, the potential of having poor drainage and fungus gnat problems increases substantially. The only containers these type of potting soils should be used in are raised gardens. Depending on the compost source, these soils can sour, grow mushrooms or become extremely hard.
Garden soil is a blend of soil and soilless ingredients. It can be used in very large containers (24” or greater) or added to native soils to enrich planting areas.
Then there is topsoil. It varies widely in composition and quality. Use it to fill holes in the yard, build berms or mix it will compost to increase water retention in dry garden areas.
So, when standing in the store comparing prices, don’t let price dictate your purchase. To keep your containerized plants doing well, do some bag reading. Choose the product that has aged forest products, sphagnum moss and perlite. Use the soils made from bio-solids and composted materials to improve the sand in the yard. When you’re done, go wash the dirt off your hands.
Every time we have a dry period in spring or summer, I get those predictable calls about some mysterious pest that’s playing havoc in lawns.
Dry spots in lawn. Photo credit: Larry Williams
Without realizing it, the caller usually describes a textbook example of dry spots in a lawn. And many times that’s what the problem areas are – dry spots.
Dry spots are the result of imperfections in an irrigation system. They are revealed during dry weather. Adequate rainfall masks the imperfections in an irrigation system.
Possible imperfections are many. The homeowner may easily fix some irrigation system problems while other problems may require the expertise of a licensed irrigation contractor. There may be too few sprinkler heads for adequate coverage, insufficient pressure to operate each zone, incorrect choice of nozzles or wrongly mixing rotors with spray heads on the same zone. The cause for dry spots may be as simple as a maladjusted spray head, a broken spray head, a plugged nozzle, a tree or shrub blocking the water, grass that has grown over a pop-up spray head, etc.
Regardless of the cause, there are a couple of simple tests that can help confirm that the problem areas are to be blamed on lack of sufficient water vs. a mysterious pest.
First, check the affected areas by taking a soil sample in the root zone. Use a soil probe or shovel to remove a core of soil to a depth of 6 to 8 inches. Visually inspect and feel the soil sample for moisture. Do the same test in an area of the lawn that looks normal and compare the difference. It should be obvious if there is a difference in moisture between the areas tested.
The second test involves placing several empty straight-sided cans such as tuna fish cans in the affected area and several in a “normal” area of the lawn. Then let the irrigation system run long enough to collect some water in the cans. Compare the amount of water collected in the two areas. It should be obvious if there is a difference in the amount of water applied in the areas tested.
These tests are cheaper, less trouble and more environmentally friendly as compared to purchasing and applying pesticides for nonexistent pests as a result of incorrectly diagnosing the problem. If these tests do not identify the problem as lack of water, you may have a lawn pest. But don’t guess.
Occasionally inspect your irrigation system while it’s running for obvious, easily corrected problems such as a maladjusted or broken spray head. The following UF/IFAS Extension publications will help with your inspection. https://edis.ifas.ufl.edu/entity/topic/residential_sprinkler_systems
potting mix are often used interchangeably, but there is a significant difference. Potting soil contains compost or the flora responsible for the breakdown process. Potting mix is soil-less. It is a blend of sphagnum moss, coir, bark, perlite and/or vermiculite. While these are natural occurring materials, they are in their original state. No decomposition has occurred. In the absence of compost, the resulting potting mix is sterile and free of fungus spores and insect eggs. Potting mixes are excellent choices for container growing, especially for house plants. The sphagnum moss, coir and bark hold and release water and nutrients, while the vermiculite or perlite keep the mix loose and well-drained. Some blended products add microbes, which then requires the word soil be added to the packaging. These are still suitable for potted plants.
