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Summer Irrigation Tips

July’s hot summer weather has given way to August’s 31 days of what will likely be temperatures and humidity equally elevated and intense. Wishes for November’s cooler thermometer reading are already creeping into daily conversations. The lawns and gardens in Wakulla County have rains as a mitigating factor to counteract the wilting potential of normal to excessive temperature readings. Unfortunately the arrival of water from above is not on a set or easily predictable schedule.

Traditionally, summer is the wettest season in Florida, with more than half of the annual rainfall occurring during the June to September “wet season”. Florida’s highest average annual rainfall occurs in the Panhandle with averages exceeding 60 inches per year. The Pensacola and Tallahassee weather stations are listed among the ten “wettest” stations in the nation. Still, this pattern of seasonal precipitation can vary greatly between locations, years and even days.  This variability often results in the need to water the lawn, landscape and garden. By following a few guidelines, you can produce the best results for plants under stress and conserve a vital and limited resource.

It is most efficient to apply water between 5:00 a.m. and 10:00 a.m. for several reasons. Only water that is in contact with roots can be absorbed by the plant. If water is applied after 10:00 a.m., a substantial portion of it will evaporate before it reaches the roots; more will then need to be applied and this resource’s productivity will be reduced. Never water late in the afternoon as evaporation will still be a problem, and wet turf and plants will invite a variety of fungal diseases to flourish as night settles.

Photo Courtesy: Les Harrison, UF/IFAS Wakulla County Extension

In the case of landscapes and gardens, water should be applied only when the moisture in the root zone system has been depleted to an unacceptable level, usually by 1/2 to 2/3 of the stored soil-water. There are several ways to determine when the soil-water reservoir has been depleted beyond an acceptable level.  The simplest method is a visual inspection of the turf or plants. Common symptoms of water stress include leaf color changes to a bluish-gray tint, footprints which linger long after being pressed into the grass and curled or folded leaf blades. Be sure the sprinklers are delivering water to the target area as water which misses the soil and is applied to hard surfaces such as driveways and sidewalks will be wasted. It also may pose an environmental problem in the form of runoff.  Surface runoff that flows past the landscape will usually reach streams, ponds, or the Gulf of Mexico. If it picks up pollutants along the way, they too will reach the surface water bodies. 

Over watering can be just as damaging as too little water. Excessive irrigation water can infiltrate the ground and reach groundwater aquifers. This issue is complicated when groundwater runs close to the surface. Excessive nutrients or pollutants can be discharged into surface bodies or move vertically into the deeper land layers.  The connected springs and sinkholes in Wakulla County make the movement of surface water a common concern.  Responsible and efficient irrigation will have positive effects far beyond the front yard.

To learn more about the effective use of water in Wakulla County’s landscapes, contact your UF/IFAS Wakulla Extension Office at 850-926-3931 or http://wakulla.ifas.ufl.edu/

Recent Weather Fueling Fungi

Florida’s panhandle has received quite a bit of rain this summer. In the last three months, depending on the location, approximately 15 to 35 inches of rain have come down, with the western panhandle on the higher end of that range. In addition to the rain, we all know how hot it has been with heat index values in the triple digits. And who can forget the humidity?! Well, these weather conditions are just the right environmental factors for many types of fungi, some harmful to landscape plants, most not.

In the classification of living things, fungi are divided into their own Kingdom, separate from plants, animals, and bacteria. They are actually more closely related to animals than plants. They play an important role on the Earth by recycling nutrients through the breakdown of dead or dying organisms. Many are consumed as food by humans, others provide medicines, such as penicillin, while some (yeasts) provide what’s needed for bread and beer. However, there are fungi that also give gardeners and homeowners headaches. Plant diseases caused by various fungi go by the names rusts, smuts, or a variety of leaf, root, and stem rots. Fungal pathogens gardeners may be experiencing during this weather include:

  • Gray leaf spot – This fungus can often show up in St. Augustine grass lawns. Signs of this fungus include gray spots on the leaf (very descriptive name!). This disease can cause thin areas of lawn and slow growth of the grass.

Gray leaf spot on St. Augustine grass. Credit: Phil Harmon/UF/IFAS.

 

  • Take-all root rot – This fungus can attack all our warm-season turfgrasses, and may start as yellow leaf blades and develop into small to large areas of thin grass or bare patches. The roots and stolons of affected grasses will be short and black.

 

Signs of take all root rot. Credit: UF/IFAS.

Powdery mildew – This fungus can be found on many plants, from roses to cucumbers. It looks like white powder on the leaves and can lead to plant decline.

  • Armillaria root rot – This fungus can infect a variety of landscape plants, including oaks, hickories, viburnums, and azaleas. Symptoms can include yellowing of leaves and branch dieback, usually in adjacent plants. Old hardwood stumps can harbor this fungus and lead to the infection of nearby ornamentals.

Because fungi are naturally abundant in the environment, the use of fungicides can temporarily suppress, but not eliminate, most fungal diseases. Therefore, fungicides are best used during favorable conditions for the particular pathogen, as a preventative tool.

Proper management practices – mowing height, fertilization, irrigation, etc. – that reduce plant stress go a long way in preventing fungal diseases. Remember that even the use of broadleaf specific herbicides can stress a lawn and exacerbate disease problems if done incorrectly. Since rain has been abundant, irrigation schedules should be adjusted to reduce leaf and soil moisture. Minimizing injury to the leaves, stems, and roots prevents stress and potential entry points for fungi on the move.

If you think your landscape plants are suffering from a fungal disease, contact your local Extension Office and/or visit the University of Florida’s EDIS website at http://edis.ifas.ufl.edu for more information.

The Grass is Getting “Hungry”

The Grass is Getting “Hungry”

(UF/IFAS photo Thomas Wright)

Northwest Florida’s weather patterns can present challenges to maintaining a health lawn. Heavy rains promote fast growth and relentless sunshine causes lawns to fade.  In the last 200 days we have received at least 68 days of rain.  While the rest of Florida was experiencing record drought, the Panhandle was experiencing torrential downpours.  With every drop of rain your spring fertilizer is being metabolized by the lawn, reducing how many nutrients remain in the soil.  Even the best slow-release fertilizer will only last 3-4 months.  The message is: “It’s time for more fertilizer.”

A healthy lawn is an important component of the urban landscape. Not only do lawns increase the value of a property, they also reduce soil erosion, filter stormwater runoff, cool the air, and reduce glare and noise.  A healthy lawn effectively filters and traps sediment and pollutants that could otherwise contaminate surface waters and groundwater.  Lawns require nutrients throughout the growing season to stay healthy.  In Northwest Florida the growing season is typically April to October.

Proper fertilization consists of selecting the right type of fertilizer and applying it at the right time and in the right amount for maximum plant uptake. The type of fertilizer should be based on a soil test, available through UF/IFAS Extension. The timing of application and amount of fertilizer is dependent on the research-based recommendations for the grass species and the fertilizer analysis of the product being used.

Chart excerpted from Florida Friendly Landscaping publication

Select only a fertilizer that states that the product is for use on residential turf. Do not use a fertilizer meant for flower or vegetable gardens on lawns. By Florida Administrative Code, Rule 5E-1.003, the Urban Turf Rule requires that the fertilizers being applied to residential lawns are labeled for the site and the application rates be followed.  Typically, these products will contain both slow-release nitrogen and low or no phosphorus.  Slow-release nitrogen will provide a longer-lasting response from the grass and reduces the potential for burning. For more information on the Urban Turf Rule go to: http://www.edis.ifas.ufl.edu/pdffiles/EP/EP35300.pdf.

With frequent rain the soil is also losing iron. Keep in mind that the green fading to yellow appearance in your lawn may be an iron deficiency.  Before applying your summer fertilizer put out a liquid chelated iron.  It will improve the health of the lawn while you are trying to find a dry day to fertilize.  While it is necessary to water in fertilizer with ¼” of water to reduce burn potential and volatilization, never apply fertilizer when heavy rain is expected.  The rainfall over ¼” can encourage runoff and/or leaching of that fertilizer, which can be costly and environmentally harmful.

The Predatory Praying Mantis

The Predatory Praying Mantis

 

Praying Mantis, Image Credit Les Harrison

Summertime is bug time in the Florid Panhandle.  The weather has provided enough rain for the bugs which depend on a supply of foliage and the temperatures have been ideal for a population explosion.

Stink bugs, leaf-footed bugs, grasshoppers, all sizes and colors of caterpillars and many more have been enjoying the lush and plentiful dining options.  More than one Panhandle homeowner or gardener has been plagued by the sudden appearance of a hoard of hungry nuisances which are eyeing the menu choices at residences.

Fortunately, nature has a way of eventually balancing all situations when left to its own devices. With the increase of the plant eaters comes a surge in those insects which restrain the excess population.

One of the most easily recognized predator insects is the praying mantis.  This beneficial insect is actually a family with multiple members, some of which have been introduced to Florida.

While there are over 2400 mantis members worldwide, Florida is home to eleven. Two of those exotics have been introduced from other regions, but considered non- invasive.

Mantises are thought to have evolved during the Cretaceous period about 100 million years ago, possibly from a predatory cockroach with similar front legs. Their closest surviving insect relatives are cockroaches and termites, both of which they will consume if given the opportunity.

Like many insects, the mantis is equipped with a tough, durable exoskeleton which provides a basis for successful close quarter combat and meal procurement. These hunters have three other advantages which create a severe vulnerability in their prey’s defense and potential for surviving a mantis encounter.

The mantis is an ambush predator which will lay in wait for the victim/meal to deliver itself.  The mantis has the instinctive ability to identify and hide in areas with high amounts of prey species traffic.

This insect is a master at stealth and camouflage. The creature’s coloration and linear shape allow it to blend into the earth tones of many settings.

To complement its ability to conceal itself in plain sight, the mantis can hold perfectly still and patiently wait for the oblivious bug to bumble into sticking range.  At that precise moment, the mantis is a blur of lethal motion.

The mantis’ forelimbs are a set of deadly spiked vices used to immobilize and secure its target.  It extends these spiny levers forward in a raised position which appears as though it is in a mealtime prayer, hence its name.

The kill technique is to impale and restrain the victim with a single stroke of the forelimbs while holding the victim securely to the mantis’ body.  On occasion the attempt fails and the mantis has to apply a more direct approach.

This insect’s beak is designed for slicing and tearing its victim’s body. Its jaw muscles provide the power to effectively employ this tool.

Depending on its stage of live, the mantis will eat a wide variety of creatures.  Early stage mantises will eat little flies and other tiny insect (including its siblings), but at maturity they will take on small reptiles and amphibians along with a variety of destructive insects.

Female mantises will even consume their prospective mates. Despite its vicious and cannibalistic nature, the praying mantis is the answer to many gardeners’ prayers.

To learn more about praying mantises and other beneficial insects, check out this EDIS site with many articles on various species of beneficial insects.

Tips on How to Manage Water in Your Landscape

Tips on How to Manage Water in Your Landscape

 

 

Although we’ve received much-needed rainfall of late, it’s still a struggle to manage moisture levels in our Panhandle landscapes this summer. During wet summer seasons, one recurring issue is that watering plants too much can have as much of an ill effect as not watering enough.

Shallow rooted plants, as well as newly set plants can easily become water stressed. Some people lightly water their plants each day. With this practice, one is only watering an inch or less of the topsoil. Most roots are deeper than this. Instead of a light watering every day, soaking the plant a few times a week works better. A soil that has been soaked will retain moisture for several days. This is a very good practice for young plants. In contrast, some people soak their plants to often. This essential drowns the roots by eliminating vital oxygen in the root zone. This can also cause root rot. Leaves that turn brown at the tips or edges, as well as leaf drop, are displaying signs of overwatering.

 

The following are tips from the UF/IFAS Florida-Friendly Landscape Program. These tips will help conserve water by providing best management practices for your landscape:

 

  • Choose the right plant for the right place: Be sure to place plants in your landscape that match existing environmental conditions.
  • Water Thoughtfully: Water early in the morning and water when plants and turfgrass start to wilt. Refrain from watering in the late afternoon or evening. This is when insects and diseases are most active.
  • Perform regular irrigation maintenance: Remember, an irrigation system is only effective if it is maintained regularly. Check for and repair leaks. If using a pop-up heads for turfgrass, point heads away from driveways and sidewalks.
  • Calibrate turfgrass irrigation system: Ideal amount of water to apply to turfgrass is ½”- ¾”. A simple test can be done to calibrate. Place a coffee or tuna cans throughout the landscape. Run the irrigation system for 30 minutes. Average the depth of the water containers. Adjust running time to apply the ½”- ¾” rate.
  • Use micro-irrigation in gardens and individual plants: Drip, or microspray irrigation systems apply water directly to the root system with limited surface evaporation.
  • Make a rain barrel: Rain barrels are an inexpensive way to capture rainwater from your roof. This can translate into a big impact on your water bill as well.
  • Mulch plants: Mulch helps keep moisture in the root zone. Two to three inches in-depth, for a few feet in diameter will work well for trees, shrubs, flowers and vegetables.
  • Mow correctly: Mowing your grass at the highest recommended length is key. Be sure to cut no more than 1/3 of the leaf blade each time you mow. Keep mowing blades sharp as dull cuts often cause grass to be prone to disease.
  • Be a weather watcher: Wait at least 24 hours after a rainfall event to water. If rain is in the forecast, wait 48 hours until irrigating. Use a rain gauge or install a rain shut-off device to monitor irrigation scheduling.

For more information on water conservation principles contact your local county extension office.

Supporting information can be found at the UF/IFAS Center for Landscape Conservation & Ecology’s Drought Toolkit: http://clce.ifas.ufl.edu/drought_toolkit/

Not all Palm Fertilizers are the Same

It is common in Northwest Florida for palms to show signs of nutrient deficiencies. In general our sandy soil is often nutrient poor and available nutrients can easily move out of soils with frequent rainfall.  In landscapes where fertilization is occurring, often the wrong types of fertilizer are applied.   Fertilizer miss-application actually increases nutrient problems for the palm.

Palms can be deficient in many nutrients but the most common deficiencies we see in landscapes are from inadequate amounts potassium and magnesium. The simple solution would be to purchase a fertilizer labeled for palms to correct the problem.  The difficulty is that most easily available fertilizers for palms do not have the correct form of nutrients that are required for the problems.  With the exception of nitrogen, all other nutrients are in a quick release form so while the slow release nitrogen lasts for 2-3 months, all other nutrients have been used up.  In response, the palm is encouraged to grow by the nitrogen but does not have enough of the other critical nutrients to carry out vital plant functions.  What we see is often older leaves that are yellowing, browning, and die off before they should because the plant is pulling any available potassium and magnesium from old fronds to support new growth.  Without the application of proper nutrients to the soil, the deficiency can continue until even new fronds are affected or the palm dies.

The fertilizer used for lawns does not have all the slow release and correct forms of nutrients for the palms. Older leaves turn yellow and brown indicating potassium deficiency. Photo by Beth Bolles, UF IFAS Extension Escambia County.

There is a solution that will help keep your palms healthy and attractive. Make sure you choose a specially designed fertilizer that has all nutrients in slow release form.  Look for an analysis such as 8-2-12-4 (Nitrogen-Phosphorus-Potassium-Magnesium).  Also read further on the label for Polymer Coated Sulfate of Potash, Magnesium Sulfate (Kieserite), and Chelate (Iron EDTA).  These are the forms of nutrients that will be beneficial to your palms.

Look in the area ‘Derived From’ (outlined in blue) on your fertilizer label to find the forms of nutrients. Photo by Dr. Monica Elliott, US/IFAS Extension.

If you have a mixed landscape where the palms are planted in the lawn, be sure to keep all lawn fertilizers out of the root zone of the palms. Lawn fertilizers do not have the correct forms of nutrients for palms. Remember also that palms roots extend many feet beyond the palm canopy so your ‘no lawn fertilizer zone’ may be past the mulch ring.

The recommendation from the University of Florida is 1.5 pounds of fertilizer over a 100 square foot area. Broadcast this on top of the ground and lightly water after application.  In North Florida, you will likely apply the correct palm fertilizer about at least two times in May and end of August or 1st of September.  If you are not able to use a palm fertilizer with the correct form of slow release nutrients, it is best not to fertilize palms at all.