By Les Harrison
Wakulla County Extension Director
The holiday season in north Florida brings the inevitability of cold and frosty weather. While nothing complements eggnog or hot chocolate like a chill in the air, some plants do not appreciate the dropping temperatures.
Homeowners and gardeners face a new set of challenges dealing with the effects of cold weather as seasonal changes set in. A little planning and creativity will save many delicate plants for the return of warmer weather.
Many people want to know when plants will need protection. Depending on the plant, the point of freezing is a good rule of thumb. Freezes in Leon County typically occur from mid-December on, so preparations should be made ahead of the chill. When listening to the forecast, note the difference in terms used for cold weather conditions. Frost, freeze, and hard freeze all describe specific and different circumstances.
Frost is when water vapor freezes on surfaces. It happens on clear nights with still air and may even happen when air temperatures are above freezing. Freezing is when northern air moves in and causes temperatures to drop below 32 degrees Fahrenheit. This condition commonly involves low humidity and wind, making drying out a big problem for plants. A hard freeze is when temperatures dip below 28 degrees Fahrenheit. Many tropical plants will survive a few degrees below freezing for brief periods, but extended periods of freeze or heavy frost may require lights or other heat used safely with a cover.
In Florida’s Big Bend most of the risk for sustaining freeze damage happens during and in the weeks after the busy holiday season. People are busy, schedules are disrupted, and the distractions, pleasant as they are, may cause homeowners to miss a critical freeze alert.
This holiday distraction is a good reason to get ready now in preparation for problem weather to come. Some plants can be moved indoors for the holidays and incorporated into the interior décor, rather than cramming them last-minute into a clutter when a freeze is predicted.
While removing the holiday decorations from storage, identify old sheets, blankets, and drop cloths which can be used as covers for tender plants which must remain outside. Test potential covers beforehand to assure all plants are thoroughly covered. It is best if the covers enclose the plant entirely without crushing it. Heavy blankets are great insulation, but only a good idea on the sturdiest of plants.
A tomato cage or other support structure can be used to keep the weight of covers off the plant. Covers also need to be secured at the ground with pins or weights to make sure cold air does not enter from below and fill the cover.
Finally, keep storage bins handy and remove the covers in the daytime if temperatures are above 55 degrees Fahrenheit. Monitor weather reports and react accordingly so the area’s tender and tropical plants see another spring in a few more months.
Les Harrison is the UF/IFAS Wakulla County Extension Director and Agriculture and Natural Resources Agent. For gardening questions, email us at AskAMasterGardener@ifas.ufl.edu