Q: I have citrus fruit left on my tree. How can I tell if the fruit is still good to eat?
A: Citrus fruit usually remains damage free until temperatures drop between 26 and 28ºF for one to two hours. Generally, if the fruit is firm looks good, smells good, and tastes good, it is edible. After frozen fruit thaws, it will have a spongy feel. Cut the fruit open and examine the membranes between the sections. If white spots appear, the fruit was likely frozen. Discard damaged fruit.
Q: Does covering plants during a freeze help?
A: Covering a plant without additional heat is primarily a method of protecting against frosts rather than freezes. Drape the covering to the ground to trap heat under the covering. When covering plants, it’s best to use cloth rather than plastic. Heat from an ordinary light bulb placed under the covering will provide additional cold protection.
Q: When should protective covers be removed from plants following a freeze?
A: You can leave cloth-type covers such as sheets and blankets over the plants as long as the temperatures are dropping to freezing at night and are rising to no more than the 50s during the day. If plastic covers are used, remove them when temperatures rise above freezing. Remove all covers when night-time temperatures are consistently above freezing. Leaving a plant covered day after day may cause the plant to break dormancy under the warm covering. The plant will then be more susceptible to cold injury during the next freeze.
Q: How soon should I prune and/or fertilize cold injured plants following a freeze?
A: If you prune immediately after a freeze, you may cut away live wood that does not have to be lost. Leaves and branches, which have been killed, can help protect the rest of the plant when the next freeze strikes, Pruning and fertilizing can force a plant to produce new growth. The new growth will be more susceptible to the next freeze. When new growth occurs in spring, you’ll know what survived and what didn’t. That’s the time to prune and/or fertilize.
Cold weather will come and go throughout our North Florida winters. On average, our last killing frost occurs around the middle of March. Be prepared to protect your prized plants each time freezing weather is predicted. As spring approaches, you’ll have a better idea of what survived and what did not. In the meantime, try not to do anything to stimulate new growth too soon.