Planning For A Freeze

Planning For A Freeze

By far, the most widely used method of cold protection in Florida is the application of water. When using water for cold protection, growers must operate their irrigation systems to keep their crops from being damaged, while at the same time minimizing water use.

The Florida Automated Weather Network (FAWN) is a statewide system of 35 automated weather-observing sites — located from Homestead to Jay (near Pensacola) — that collect data every 15 minutes. The data, along with several calculated products and weather-related tools, are delivered to the public via the Internet and can also be retrieved via a telephone voice message system. FAWN has taken real-time weather information and developed the Cold Protection Toolkit — a step-by-step decision-making guide for using water for cold protection.

Temperature Tools

Inherent in every crop is a temperature at which cold air will begin to cause damage. So, the first step in the cold protection process is to determine the critical temperature for a given crop. FAWN’s online guide, Determining Critical Freezing Temperatures For Plants In Florida, provides assistance with determining the critical temperature for various crops in the state.

Next, the Fruit Frost Station Forecast tool provides a big-picture overview of whether cold protection may be needed during the upcoming week by retrieving a seven-day forecast for 180 of the prior National Weather Service (NWS) Fruit Frost Forecast locations.

On a night when critical temperatures are possible, the Forecast Tracker displays the NWS forecasted temperature and the observed temperature at any FAWN site on a 48-hour graph; a critical temperature can also be displayed as well.

The Minimum Overnight Temperature tool further evaluates the likelihood of the forecasted temperature occurring using the Brunt equation to estimate the minimum overnight temperature at each FAWN site. The sunset air and dew point temperatures can also be manually submitted for an estimate at the user’s location.

There is always a risk of further cooling due to evaporation when using irrigation systems for cold protection. The Evaporative Cooling Potential tool categorizes the evaporative cooling potential at each FAWN site.

Finally, the Wet-Bulb Based Irrigation Cutoff Temperature tool — which utilizes the basic cold-protection recommendation to discontinue irrigation when the wet bulb temperature reaches the critical temperature of the crop being protected — calculates an air temperature at which the wet bulb and your critical temperature would be equal. Air temperature, dew point temperature, and wind speed can also be manually submitted to determine the cutoff temperature at any location.

Substantial Savings

It has been estimated that use of these tools can save two hours of irrigation per cold event. During a relatively warm winter, one to three nights may require cold protection for a total savings of two to six irrigation hours. A cold winter, however, may produce four to 10 nights requiring cold protection for a savings of eight to 20 hours. Depending on the number of nights that need protection, billions of gallons of water and millions of dollars can potentially be saved by using FAWN Cold Protection tools.

The FAWN Cold Protection Toolkit provides step-by-step guidance for using water for cold protection by first helping users find their critical temperature, determining generally which upcoming nights might require cold protection, then guidance during individual cold events for when to start and stop irrigation. To use the FAWN Cold Protection Toolkit, visit http://fawn.ifas.ufl.edu, select Tools, and then Cold Protection Toolkit.

FAWN thanks the University of Florida/Institute of Food and Agricultural Sciences for financial support and infrastructure; the Florida Department of Agriculture and Consumer Services, South Florida Water Management District, Southwest Florida Water Management District, and St. Johns River Water Management District for their ongoing financial support.

Leave a Reply

Featured Stories
Tomato bug
Insect ControlStop Tomato Bugs From Sucking Your Crops Dry
May 21, 2015
Learn how to identify, the survival and spread, as well as management methods of this vegetable pest. Read More
UF/IFAS developmental biologist Dennis Gray looks at the progress of grapevines in a vineyard.
Crop ProtectionResearcher Using ‘Precision Breeding’ To Create Disease-Resistant Winegrapes
May 20, 2015
Breakthrough would mean significant savings on pesticide and fungicide sprays. Read More
Spraying indoor citrus
Protected AgricultureInterest Continues To Grow In Protected Citriculture
May 20, 2015
Inside move could put producers in prime scoring position. Read More
Expansion groundbreaking for Southwest Florida Research and Education Center
CitrusSouthwest Florida Research And Education Center Embracing New Expansion
May 20, 2015
A 7,000-square-foot addition to the UF/IFAS facility will house labs and offices for potential new faculty members. Read More
storm clouds
CitrusSouth Florida Rainy Season Could Wind Up On Drier Side
May 20, 2015
National Weather Service anticipating El Niño to play a hand in possible below-normal conditions. Read More
Food SafetyProduce Safety Alliance Offers Course To Become A Certified Trainer
May 20, 2015
The Produce Safety Alliance (PSA) has announced dates for their first two Train-the-Trainer courses this June. The first of the Read More
GrapesMatthew Fidelibus To Be Recognized For Extension Work
May 20, 2015
The American Society of Enology and Viticulture (ASEV) recently announced that Western Fruit Grower™ magazine contributor Matthew W. Fidelibus, of Read More
Apples & PearsGrants Available For Farmworker Education
May 19, 2015
Grants are available for farmworkers and their families interested in attending adult educational programs through the Washington Apple Educational Foundation Read More
Fruits$10 Million Available For California Water Conservation Program
May 19, 2015
Applications for the California Department of Food and Agriculture’s (CDFA) California State Water Efficiency and Enhancement Program (SWEEP) are now Read More
CitrusBad Weather Or Not, Preparation Always On Radar For Florida Farmers [Opinion]
May 19, 2015
You cannot prevent a natural disaster from taking everything you have, but you can lessen the blow if and when it happens. Read More
The Latest
Tomato bug
Insect ControlStop Tomato Bugs From Sucking Your Crops Dry
May 21, 2015
Learn how to identify, the survival and spread, as well as management methods of this vegetable pest. Read More
UF/IFAS developmental biologist Dennis Gray looks at the progress of grapevines in a vineyard.
Crop ProtectionResearcher Using ‘Precision Breeding’ To Cr…
May 20, 2015
Breakthrough would mean significant savings on pesticide and fungicide sprays. Read More
Spraying indoor citrus
Protected AgricultureInterest Continues To Grow In Protected Citriculture
May 20, 2015
Inside move could put producers in prime scoring position. Read More
Expansion groundbreaking for Southwest Florida Research and Education Center
CitrusSouthwest Florida Research And Education Center Embraci…
May 20, 2015
A 7,000-square-foot addition to the UF/IFAS facility will house labs and offices for potential new faculty members. Read More
storm clouds
CitrusSouth Florida Rainy Season Could Wind Up On Drier Side
May 20, 2015
National Weather Service anticipating El Niño to play a hand in possible below-normal conditions. Read More
Food SafetyProduce Safety Alliance Offers Course To Become A Certi…
May 20, 2015
The Produce Safety Alliance (PSA) has announced dates for their first two Train-the-Trainer courses this June. The first of the Read More
GrapesMatthew Fidelibus To Be Recognized For Extension Work
May 20, 2015
The American Society of Enology and Viticulture (ASEV) recently announced that Western Fruit Grower™ magazine contributor Matthew W. Fidelibus, of Read More
Apples & PearsGrants Available For Farmworker Education
May 19, 2015
Grants are available for farmworkers and their families interested in attending adult educational programs through the Washington Apple Educational Foundation Read More
Fruits$10 Million Available For California Water Conservation…
May 19, 2015
Applications for the California Department of Food and Agriculture’s (CDFA) California State Water Efficiency and Enhancement Program (SWEEP) are now Read More
CitrusBad Weather Or Not, Preparation Always On Radar For Flo…
May 19, 2015
You cannot prevent a natural disaster from taking everything you have, but you can lessen the blow if and when it happens. Read More
Sweet CornGrower, Marketer Team Up To Launch Line Of Single-Serve…
May 19, 2015
Next Level Fresh, LLC announced the introduction of Fresh Life Harvest Whole Ear Gourmet Sweet Corn. The concept was developed Read More
CitrusSave Your Greenhouse Structures From Storms
May 19, 2015
Make sure your protected agriculture components are prepared for whatever may blow this way. Read More
FruitsGreen Fruitworm Numbers High In Pennsylvania
May 19, 2015
In their latest insect report, David Biddinger and Grzegorz Krawczyk, tree fruit entomologists discuss the timing of pest control applications Read More
Apples & PearsApple Scab Alert
May 18, 2015
Kari Peter of Penn State University Extension warned growers of possible apple scab and fire blight infections following the rainy Read More
FruitsUSDA To Invest $21M To Help Growers Cope With Drought
May 18, 2015
USDA’s National Resources Conservation Service (NRCS) will allocate $21 million for growers and ranchers to apply conservation practices in the Read More
BB Hobbs Inc. warehouse in Plant City, FL
CitrusBB Hobbs Bolsters Business In Central Florida
May 18, 2015
Irrigation specialists celebrate opening of new branch warehouse in Plant City. Read More
Disease ControlHow To Control Disease During Rainy Weather
May 18, 2015
The recent warm, wet weather conditions are prime for fungal and bacterial diseases, says Annemiek Schilder of Michigan State University Read More
FertilizerBioWorks Launches New Fertilizer And Biostimulant
May 15, 2015
BioWorks, Inc., launched ON-Gard, a new organic fertilizer and biostimulant. ON-Gard is a 100% plant-derived product with organic nitrogen and Read More