Florida Chill Hours Map
The University of Florida Institute of Food and Agricultural Science (UF-IFAS) tabulates chill hours (as opposed to average minimum temperature) in more detail for Florida and their map can be used to identify the expected range of chill hours for areas in Florida.
Be sure to match your plants by Hardiness Zone and by Chill Hours.
In order to bloom in spring, deciduous fruit trees like peaches, plums, and nectarines all must go through the plant equivalent of a long winter's nap.
They need a dormancy period with a certain number of chilling hours, when the temperature drops below 45 degrees Fahrenheit. The exact number of chilling hours depends on the fruit tree variety, but it can be anywhere from a hundred to more than a thousand.
Here in Florida, gardeners should look for special "low chill" fruit tree varieties. Low-chill peaches, plums, and nectarines need just 100 to 525 chilling hours per year, making them better suited for our mild winters. Low-chill apples are also available, though there are fewer varieties that work well in Florida. 1
Chill Hour Accumulation in Florida
Below 45F (7.2C) through February 10th
There are many sources from which to gather this data, including the Florida Automated Weather Network FAWN. The state of Florida has several zones with different chill unit accumulations to aid in selecting a peach cultivar. 2
Counties of Florida Map
Plant Hardiness Zone Map
Average Temperatures in Florida
General Index Page
1 "Chill Hours." gardeningsolutions.ifas.ufl.edu. Gardening Solutions, UF/IFAS. 23 Oct. 2013. Web. 10 Aug. 2016.
2 Olmstead, Mercy, Chaparro, Jose, Andersen, Pete, Williamson, Jeff and Ferguson,James. "Florida Peach and Nectarine Varieties." edis.ifas.ufl.edu. This document is Circ. 1159, a publication of the Horticultural Sciences Department, UF/IFAS Extension First published Nov. 1995 under the title, "Peaches and Nectarines for Central and North Florida." Revised May 2013. Web. 4 Sept. 2014.
Fig. 1 Florida Chill Hours Map. N.d. ifas.ufl.edu. Web. 12 Apr. 2014.
Fig. 2 Chill Hour Accumulation in Florida (Below 45F [7.2C] through February 10th). N.d. edis.ifas.ufl.edu. Outline map courtesy of the Florida State Historical Society. Web. 16 Apr. 2015.
Fig. 3 State Based County Outline Map - Florida. General Reference Maps. 7 Oct. 2002. census.gov/geography.html. Web. 9 Aug. 2016.
Fig. 4 USDA Plant Hardiness Zone Map Florida, 2012. planthardiness.ars.usda.gov. Web. 9 Aug. 2016.
Fig. 5 Average high and low temperatures for various Florida cities. N.d. en.wikipedia.org. Web. 10 Aug. 2016.
Published 19 Feb 2013 KJ. Last update 17 Nov. 2016 LR