Many of us experienced our first freezing temperatures in the Panhandle last week. As we welcome winter, here are some helpful resources to prepare your plants when temperatures dip in the months ahead:
One tip you’ll often see in these recommendations is to water your plants before a freeze. At first, this might seem counterintuitive, but wet soil can actually help your plants weather freezing temperatures for several reasons.
Soil naturally has small pockets of air. UF/IFAS Photography: Tyler Jones.
Water’s ability to absorb and hold heat—known as high specific heat—makes it a powerful tool against cold stress. Dry soil contains air spaces that don’t hold heat well. By watering your soil, you replace those air pockets with water, which absorbs more heat during the day and releases it slowly at night. This helps keep the soil and roots warmer than the surrounding air. Covering plants with sheets and frost cloth can help trap this warmth around the plants.
Dehydration from freeze damage can make leaf tissue look similar to drought stress. UF/IFAS Photo by Cat Wofford
Beyond heat retention, water also reduces the effects of cold stress. Both freezing and drought conditions cause plant cells to lose water, leading to dehydration. Water is essential for many plant functions including photosynthesis, nutrient transport, and maintaining structural support of the plant. Good water availability within the plant before the freeze helps reduce the water stress associated with cold damage. However, watering right after a freeze will not provide the same benefits because root activity slows in the cold weather.
For best results, water the soil in the morning before a freeze, focusing on the soil, rather than the leaves, as wet leaves are more prone to freeze damage. During fall and winter, plants generally require less frequent watering, so check the soil moisture before watering to avoid overwatering. Standing water can harm roots and increase stress on the plant.
Get familiar with your soil by checking moisture level before you water. UF/IFAS Photo by Tyler Jones
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.
We gardeners in the Panhandle have been spoiled by several very mild winters recently. However, it appears that this pattern will change, at least for a few days, beginning Thursday night. While forecasts vary depending upon your preferred media outlet, all agree that Calhoun County is going to experience several freezing nights (temperatures in the low 20’s to high teens for hours at a time). That’s plenty cold to kill many cold-sensitive plants, so here are a few tips to keep your treasured plants alive until warmer conditions arrive next week.
Covering plants to protect from frost, cold snap, blanketing, potted plants, horticulture. UF/IFAS Photo: Sally Lanigan.
Bring cold-sensitive potted plants inside. You can’t dig up your citrus trees and bring them in the living room but bringing cold-sensitive potted plants inside for a couple of nights is a fail-proof freeze protection method.
Water outside plants the day before extreme cold hits. It’s natural, even good, for many tender plants (perennials, bulbs, etc.) to “die” back in cold weather. This encourages dormancy and reduces pest/disease populations. However, this week could get cold enough to kill “tops” of sensitive plants AND freeze root systems. To help prevent this, water the day before a freeze as moist soil loses heat less rapidly than dry. A few degrees can make all the difference!
Apply mulch around the base of plants. Mulch helps insulate the soil and reduces radiant heat losses. For plants with a graft – like most citrus, pile mulch up around the grafted area. If the top of the plant dies back, at least it will be able to recover from above the graft (the desirable part of a grafted plant).
Cover citrus and other plants that recover slowly from cold damage. Draping a non-plastic cloth or blanket mostly helps keep frost off and freezing wind off plants but can also insulate from freezing temperatures if it covers the entire plant to the ground. It’s better than nothing.
Build a “greenhouse” around plants. You can create a simple greenhouse structure of wooden stakes, pipe, or posts and cover with plastic (making sure the plastic doesn’t touch leaf or stem tissue). Be sure to get this structure up while the sun is still shining before the freeze event to capture as much solar heat as possible. For even better results, install a lightbulb, non-LED Christmas lights, or some other heat source inside the plastic structure.
Last ditch method –turn on the sprinkler. Continuouslyrunning a sprinkler over sensitive plants can help protect them. By running water, you “insulate” the plant to the water’s temperature (above 32 F). This method requires that the sprinkler begin running before the thermometer drops below 32 degrees and must continue uninterrupted until after the freeze event is over. If you stop before the freeze is over, the water left on the plant will freeze to whatever temperature the air is, injuring or killing the plant.
We don’t have many freeze events so take a little time this week to bring sensitive plants indoors and implement one or more of the above precautionary measures in your landscape! Don’t let a few hours of very cold weather set your plants back years! For more information about cold protection in the lawn and garden, contact your local UF/IFAS County Extension Office. Stay warm and Merry Christmas!
Bananas are a great choice for your landscape, whether as an edible fruit producer or simply as an ornamental, giving your space a tropical vibe.
Bananas are native to southeast Asia, however, grow well across Florida. Complementary plants that can be paired with bananas in the landscape are bird of paradise (banana relative), canna lily, cone ginger, philodendron, coontie, and palmetto palm, just to name some.
Bananas are very easy to manage during the warmer months. Bananas are water loving, and that’s putting it lightly. Planting in vicinity of an eave on your home is a good measure for site suitability. Roof rainwater will drastically increase the growth of the banana tree and decrease the need for supplemental irrigation. Banana trees will need full sun and high organic moist soils create the best environment. For nutrition, a seasonal one-pound application of 6-2-12 fertilizer is a good practice to sustain older trees. Young trees should be fertilized every two months for the first year at a rate of a half-pound.
Musa basjoo is one of the most cold hardy banana varieties. Photo Credit: University of Florida/IFAS Extension
If there is a con to banana trees, it’s their cold hardiness. Some varieties fair well and others some not so much. ‘Dwarf Cavendish’ (Musa acuminate) is a popular variety that is found in many garden centers in the state. It produces fruit very well, but it is not very cold hardy. ‘Pink Velvet’ (Musa velutina) produces fruit with a bright pink peel, but isn’t very cold hardy either. A couple of cold hardy ornamental varieties are the ‘Japanese Fiber’ (Musa basjoo) and ‘Black Thai’ (Musa balbisiana), which is by far the most cold hardy, with the ability to easily combat below freezing temperatures.
Freeze damage on a banana tree. Photo Credit: Ray Bodrey, University of Florida Extension – Gulf County
Regardless of cold hardiness, in many cases, banana trees will turn brown after freezing temperatures occur or even if the temperatures reach just above the freezing mark, but will bounce back in the spring. Until then, it’s important not to prune away the brown leaves or trunk skin. These leaves act as an insulator and help defend against freezing temperatures. Usually, the last freezing temperatures that may occur in the Panhandle are around the first of April. So, to be safe, pruning can begin by mid to late April. When pruning, be sure to be equipped with a sharp knife, gloves and work clothes. Banana trunk skin and leaves can be quite fibrous and the liquid from the tree can stain clothing and hands.
So, what’s the best variety of fruiting bananas? Most ornamental bananas do not produce tasty fruit. If you are looking for a production banana, ‘Lady Finger’, ‘Apple’, and ‘Ice Cream’ are popular varieties, but are better suited for the central and southern parts of the state.
For more information, contact your local county extension office.
Frost on Dune Sunflower Picture by: Pam Brown UF/IFAS Extension
December is finally here and that means consistent nights of watching for dropping temperatures. Tropical plants and newly installed shrubs are susceptible to cold injury. Those colorful, blooming plants that have added a tropical look to the landscape all summer may begin to suffer when the temperatures drop below 500 F. Leaves may turn yellow and flowering stops. These plants will need to be moved inside or have temporary greenhouse built around them. But, hardy plants that haven’t established a sufficient root system will also need additional attention when the temperatures drop dramatically.
The ability of plants to endure a freeze depends on the species and the weather leading up to the extra cold night. Gradual decreases in temperatures helps plants acclimate to winter. But, a sudden one day drop of 40-50 degrees results in a rapid freeze that causes ice to form inside the plant cells. Leaf and stem tissue expands so quickly that it splits, resulting in parts of the plant incapable of transporting water and nutrients, as well as, performing photosynthesis. However, it may be late the following spring before the damage is noticed, when that section of the plant has slowly staved to death.
Cracked bark from frost
Additionally, plants can experience desiccation or drying out. This happens when dry winds and solar radiation result in the loss of more water from the leaves than can be transported by a cold root system. The resulting symptom is marginal and/or tip burning of leaves that leads to totally brown leaves.
Freezes (when the temperature drops to 320 F) are characterized as radiational or advective. Radiational freezes occur on calm, clear nights when heat radiates from the surfaces of plants, making them colder than the air due to the rapid loss of heat. If there is moisture in the air, ice will also form on the surfaces. Under these conditions, ice forms between plant cells, rather than within the individual cells. Most hardy plants can tolerate these type of freezes if they are properly hydrated.
Advective freezes occur when cold northern winds move in rapidly, dropping temperatures quickly, and causing widespread foliage desiccation. Cultivation and maintenance practices can impact a plant’s ability to endure extended periods of low temperatures. Shade-tolerant species installed under the canopy of a tree typically display less injury from radiational freezes because the trapped heat from the ground and the overhead foliage creates a microclimate. Well-watered soil around a plant will absorb solar radiation during the day and re-radiate heat over night, raising the temperature around the plants. Shrubs that are not pruned in the late summer or fall have leaves that can withstand frost and wind. But, the removal of foliage late in the growing season triggers a flush of new growth, that is very sensitive to lower temperatures. The same response can result from fertilizer applications after plant’s have slowed down in growth.
Irrigation Frost Protection on Citrus
Row Cover Picture by: Univ of Maryland Extension
So, what can you do to prepare for upcoming freezing temperatures? Begin by avoiding pruning and fertilizing at the end of the season and making sure that the plants have been watered within 24 hours of a cold night. Next, insulate against water loss and increase heat radiation by adding a three-inch of mulch, as well as, covering the trunks of sensitive trees with a commercial tree wrap. Then, consider what needs to be covered. Frost cloth or other breathable fabrics can trap heat for the night and provide a protective layer from frost settling on the leaves. It needs to be placed by mid-afternoon and removed the next day when temperatures are above 320 F. Plastic is not recommended unless the timing regime can be followed reliably and a structure is used under the material to keep the plastic off the foliage. Anchoring of the cover is critically important in the event of an advective freeze.
Finally, turn off the sprinkler system. Commercial agriculture often uses a running irrigation system to keep the leaf surface temperatures near, but not below, 320 F because sprinkling utilizes latent heat released when water changes from a liquid to a solid state. The thin layer of ice melts and re-freezes on the surface throughout the night, without ice forming within the plant tissues. For the technique to work, sprinkling must begin as freezing temperatures are reached and continue until thawing is complete. Landscape systems are not designed to deliver the amount of water over the length of time required to accomplish this type of frost protection.
When the cold nights have passed, don’t forget to check your plants for water. But, wait until winter has passed before pruning out the frost damaged stems.
