Anchor frost cloth securely to keep it tightly in place, as removing air gaps helps trap ground heat and shield plants from cold air. Photo by Molly Jameson.
Here in North Florida, mild winters are the norm, but our occasional cold snaps can be enough to wreak havoc on our gardens. As you might remember, in December of 2022 the entire Panhandle experienced temperatures dipping into the teens and low 20s for several nights in a row, with some areas reaching as low as 18°F. This kind of unexpected freeze can catch even the most experienced gardeners off guard.
While plant covers are the go-to solution for many of us, pairing them with additional techniques can offer even better protection when temperatures dip. From common cold weather protection myths to practical DIY tips that enhance your plant cover’s effectiveness, knowing your options can make all the difference during an impending cold snap.
Cold Protection Myths and Misconceptions
When a frost or freeze warning hits, there’s plenty of advice flying around. Some of it’s helpful, and some, not so much. Here are a few misconceptions to clear up:
“Lollipop” trees will allow the heat from the ground to escape, giving the tree no cold protection. Photo by Jonathan Burns.
“It’s All About Covering the Leaves”
Many gardeners believe that simply covering the leaves of their plants will provide adequate protection. However, this can lead to what’s commonly referred to as “lollipop” trees, where only the foliage is covered, leaving the trunk exposed. This is problematic because cold air can still penetrate, and the heat rising from the ground isn’t captured effectively. To ensure proper protection, the plant cover should touch the ground all around the plant to trap heat radiating from the soil, providing insulation from below. For best results, choose a medium-weight frost cloth (about 1 to 1.5 oz/yd²) made from breathable polypropylene or polyester fabric. These materials offer excellent insulation, providing about 4 to 8 degrees of temperature protection, depending on factors like cloth weight, ground heat trapped, and wind conditions. Frost cloth also allows moisture and air exchange, which helps prevent overheating on sunny days.
“A Plastic Sheet Works Just as Well as Frost Cloth”
Throwing a plastic sheet over your plants might seem like an easy fix, but it often leads to more harm than good. Plastic is non-breathable, which can trap condensation and freeze on the plant’s surface. It also doesn’t insulate well, transferring cold temperatures directly to the leaves and stems. If you must use plastic in a pinch, make sure it doesn’t touch the plants directly and that it’s securely anchored to the ground to effectively trap warmth. Be sure to remove it in the morning once temperatures start to rise to avoid overheating.
“Covering Your Plants Alone is Enough”
With PVC hoops ready to hold frost cloth and a thick layer of pine straw mulch, these raised beds are prepped for whatever winter throws their way. Photo by Molly Jameson.
While covering plants is crucial, sometimes additional steps can make a big difference. Mulching around the base of plants with a thick layer of pine straw or leaves helps insulate the soil and trap ground heat. It’s a small step that offers big protection to the roots and lower stems.
“Watering Plants Before a Freeze Doesn’t Help”
Watering the soil around your plants before a freeze is a good practice because moist soil retains heat better than dry soil. This can help keep the root zone warmer overnight. However, it’s important to focus on watering the soil rather than the leaves. Water on foliage can freeze and cause damage, so it’s best to keep leaves dry as the temperatures drop. A deep watering a day or two before the cold hits is ideal for giving your plants a fighting chance.
DIY Cold Protection Solutions
If expensive greenhouses and plant covers are out of your budget or you want to get creative, there are plenty of do-it-yourself solutions for protecting your plants:
Recycled Materials as Frost Protection
Old bedsheets, towels, or even buckets and cardboard boxes can be used in a pinch to cover smaller plants. Just be sure to anchor them down well, so they don’t blow away.
DIY Hoop Houses
A temporary hoop house can be constructed using PVC pipes as the frame and polyethylene film as the covering to protect cold-sensitive plants during freezes. Photo by David W. Marshall.
For taller or sprawling plants, construct simple hoop houses using PVC piping with breathable frost cloth or lightweight plastic sheeting. Unlike placing plastic directly on plants, hoop houses create an air gap between the plastic and the plants, which helps trap heat from the soil while preventing direct contact damage. If using plastic, seal it tightly at night to trap warmth, and open it partially during the day to prevent overheating or excessive moisture buildup as temperatures rise. These low tunnels are perfect for garden beds or fruiting plants that need a little more room under cover.
String Lights for Added Warmth
For extra protection, consider using outdoor-rated incandescent string lights (not LEDs, which don’t produce heat). Drape the lights around or near the plant under the covering to create a gentle source of warmth, which can raise temperatures by a few degrees on especially cold nights. For fire safety, keep lights from direct contact with dry materials and use only moisture-safe, outdoor lights.
Windbreaks to Stop the Chill
In areas with open landscapes, cold winds can make frost damage even worse. Planting a hedge or using temporary barriers like hay bales or pallets can shield your garden from icy gusts and protect your more delicate plants.
One of the best ways to prepare for cold snaps is to plant cold-tolerant varieties suited to North Florida’s climate. Vegetables like collards, kale, and carrots, or perennials like rosemary and garlic chives, can withstand mild freezes with little effort. If you’re growing fruit trees, look for varieties with proven cold tolerance or dwarf varieties that are easier to cover.
With a little planning and a few simple techniques, you can protect your garden from unexpected cold spells and keep it thriving through our chilliest nights.
The widespread multiple night hard freeze that occurred in North Florida near the end of December 2022 resulted in numerous citrus trees becoming severely damaged. The above ground portion of many of these trees died as a result of the extreme cold.
I talked with numerous homeowners who were concerned about their citrus trees following that weather event. Many of these homeowners earnestly and hopefully watched for any sign of new growth on their cold injured citrus trees the following spring. When new growth appeared from the lower portion of the trunk and from the roots, the homeowner became excited with a false sense of hope that their citrus tree had survived and would again produce an abundance of desirable fruit.
Cold injured citrus tree with new growth coming from rootstock. Credit: Larry Williams
Now in the spring of 2024, many of these citrus trees have somewhat regrown from those root shoots, not from the completely dead tops. In most cases, the freeze damaged, dead tops of the once large trees have now been pruned away to allow the multitude of small diameter vigorous green shoots to grow.
Most purchased citrus trees are grafted. So, what survived and is now regrowing is coming from the rootstock, not from the original, desirable, edible fruit producing top. That desirable top was completely killed.
To better understand this scenario, perhaps a basic definition of grafting will help. This definition was taken from a University of Missouri Extension publication on grafting. “Grafting is the act of joining two plants together. The upper part of the graft (the scion) becomes the top of the plant, the lower portion (the understock) becomes the root system or part of the trunk.” Understock is also known as rootstock.
Grafting involves joining two different individuals. These individuals have to be closely related. For example, citrus can be grafted to other types of citrus and peaches can be grafted to other types of peaches. But citrus cannot be grafted to peaches.
The rootstock was selected because of some beneficial trait(s): resistant to a root pest, superior cold hardiness, imparts a dwarf growth habit to the top, etc. But the same rootstock produces undesirable fruit: bitter, hard, extremely seedy, etc. The top (scion) was selected because of a superior fruit: sweeter, bigger, more disease resistant, etc. But the same scion produces an inferior/weak root system. So, grafting the two together allows for the “best of both worlds.”
When all that is left is originating at or below the graft union or rootstock, the eventual resulting fruit will usually be undesirable, sometimes not edible.
So unfortunately, the best option in this scenario is to start over with another healthy grafted tree that is well suited for the potential cold weather of extreme North Florida.
Fall, winter and even early spring can be a rollercoaster ride of temperatures here in Northwest Florida. One week it dips to freezing for a short time and the next week it rises to spring-like temperatures. We need to hold on for this ride of up and down temperatures and not overreact too soon.
Following the sudden ride down to the lower temperatures, we may think winter is over. But we don’t see the next drop in temperatures that’s coming, as we are experiencing the ride upwards in temperatures.
On average, it’s not until we reach mid-March that we expect our last killing frost. A killing frost is heavy enough to kill tender plant growth. And, we can have light frosts well into the latter part of March and into early April. This is particularly true in the more northern portions of our Panhandle Counties.
The main point is to not get spring fever too early and encourage new plant growth by pruning or fertilizing too soon.
When landscape plants freeze, the first impulse may be to get out the pruning shears and cut away dead and dying leaves and branches. But this isn’t a good idea. Pruning can force new tender growth that is more likely to be injured by the next freeze. And, you can’t tell how much damage has been done until plants start new growth in spring. If you prune immediately after a freeze, you may cut away live wood that doesn’t have to be lost. Also, leaves and branches, which have been killed, can help protect the rest of a plant against further cold injury.
Some people want to “jump start” their lawns before our weather will allow our grasses to grow. Waiting allows for more efficient use of the lawn fertilizer. You will not injure your lawn by waiting but you can certainly injure your lawn by fertilizing too early.
So, have patience, allow your lawn to green up on its own and then fertilize, even if it’s not until April or May.
Finally, be a little philosophical. If you do lose one or two of your tender ornamentals, so what? Worse things could happen. And now you have a chance to add something new, perhaps some species native to our area that is not as subject to cold damage.
Even with this winter/spring rollercoaster ride, with thousands of plants to choose from and a generally mild climate, who can complain?
Interest in cultivating date palms in North Florida is on the rise. Highly regarded by gardening enthusiasts, the date palm is grown as an ornamental and for its delicious fruits with the added bonus of medicinal properties.
Growing date palm in North Florida poses challenges due to the region’s moist and cooler climate with temperatures occasionally dipping below freezing. Date palms, which typically thrive in hot, arid conditions, include two notable species: True date palm (Phoenix dactylifera) renowned for its tasty fruit and the Canary Island date palm (Phoenix canariensis), known for its substantial size and edible but less flavorful fruits. There is also (Phoenix sylvestris), known as the Sylvester date palm or wild date palm.
Characterized by a slow growth rate, date palms can, in certain environments, grow to towering heights of up to 80 feet. Their pinnately compound leaves, ranging from blue-green to gray-green, can stretch up to 20 feet in length, featuring leaflets of 1 to 2 feet that form a distinctive “V” shape along the rachis. Date palms possess ornamental appeal, thanks to its textured trunk, striking blue-green foliage, and vibrant orange inflorescences. However, date palms do generate some concern because of the litter created by its fallen fruits. Its wide crown offers limited shade due to its relatively sparse canopy.
To flourish, date palms require well-drained, neutral to acidic soil and an abundance of direct sunlight. A plus is their ability to thrive in confined root spaces. North Florida’s sporadic frost and cold spells necessitate protective measures for date palms during the colder months, such as covering them with frost cloth or employing mulch around the base to insulate the roots. Some palm enthusiast grows them in sheltered location but occasional freeze damage to foliage can be expected.
Alternatives
Gardeners in North Florida seeking a cold-hardy alternative might try the pindo palm (Butia odorata), which is an excellent choice. Although it isn’t a true date palm, its feathery fronds provide a tropical ambiance to the landscape. Other palm species adaptable to North Florida’s wintry conditions include windmill palms, needle palms, and sabal palms. These options vary in their ultimate height and visual characteristics.
While it’s possible to grow date palms in North Florida, it’s important to understand that success may not be guaranteed, and you may need to provide extra care and protection to help your trees thrive in the region’s climate.
For more information contact your local extension office or visit:
Some citrus is recovering from our December 2022 hard freeze and pruning will be needed. Learn to identify your tree’s graft and how to prune away any rootstock material with UF IFAS Extension Escambia County.
Palms in North Florida suffered serious damage as a result of freezing weather in December 2022. As spring approaches, we will be looking to see if the palms will recover. Learn what to do now and what to expect from your palms with UF IFAS Extension Escambia County.