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?
January and February are typically the coldest months in Florida and plants can be damaged by low temperatures. But with your help, cold-damaged plants can often recover.
Cold damage on Ornamental. Image Credit Eddie Powell UF IFAS Extension Walton County
After a freeze, see if your plants are dry. Even injured plants need water.
Plants, however can be greatly damaged if the temperature drops suddenly. They have no time to acclimate to the freezing temperatures. Plants are damaged when ice crystals form the plant cells. The crystals expand, rupturing the cell walls and preventing the plants from maintaining shape. If severe, this can kill tender plants. On hardier plants, damaged foliage will appear wilted and curled down. In a few hours or days, it will darken and turn black. Flowers and buds my die, blacken, and drop to the ground if exposed to cold temperatures. Damaged flowers will not develop into fruit. Young branches and new growth are especially susceptible and may also blacken and die.
After freezing temperatures occur, remove damaged leaves and flowers as soon as they turn brown or black. This will help prevent diseases from attacking the plant. Pruning should be postponed until cold temperatures are no longer expected and new growth begins to appear on the plant. This is to make sure that live wood, which appears dead from losing its leaves, is not mistakenly removed from the plant. Cold damaged wood can be detected by examining the cambium layer (under the bark) of the plant. If it has black or brown discoloration, it is damaged and should be pruned back behind those points.
Living cambium layer beneath bark. Image Credit UF IFAS Pinellas County
Protect your plants from cold temperatures during the next cold front. Do this by moving potted plants indoors and covering tender landscape plants with a protective covering. Protective covering can include old bed sheet, pieces of material or fabric, and cardboard boxes. Be careful not to let the protective covering touch the plants. The surface of the covering will become as cold as the air temperatures and may damage any tender leaves it come in contact with. Also, don’t forget to remove the covering the next day when temperature raises this is important so the plants do not “bake” in the warmer temperatures. Plants placed near the house, lights, or other structures, which shelter them from wind, will be more protected than those fully exposed to the cold air.
Whatever you do, even if your landscape ornamentals have already suffered some cold injury. Do not relax your guard more frigid weather may be on the way. So, be prepared to keep your prized plants, as warm as possible, each time the weatherman predicts freezing temperatures. Plants should be fertilized in the spring, to encourage new growth. Try not encouraging any new growth, until all frost danger has passed.
