The freeze over the weekend was certainly a deep one

In an instant our landscapes and turf went from green to various shades of brown. While there are a lot of articles and blogs telling us not to prune out our dead plants, there is not a lot out there telling us what to do with our citrus. With citrus, patience is required. However, by following the guidance from the University of Florida we can take the necessary steps to help our trees recover.

The ability citrus trees to recover from cold damage is directly proportional to the health and vigor of the tree

Trees with insect damage, disease, or nutrient deficiencies are more likely to have more severe cold damage. With citrus greening running rampant throughout northeast Florida, the potential for severe damage increases.

Symptoms of cold damage to citrus come in many different forms

The greater the cold damage, the more severe the symptom. For instance, citrus leaves lightly damaged by cold may simply droop but remain green. While leaves with heavy cold damage are brown and brittle. Branches with heavy cold damage may die entirely or develop splits with damage to the cambium while some branches may have very little apparent damage at all.

Fruit drop may occur in heavily damaged fruit

Often this fruit is inedible as ice has formed inside the fruit and created extensive internal injury. Fruit that remains on the tree may show signs of freeze/ice damage by the appearance of water-soaked areas inside the segments. You may want to sample the fruit still on the tree starting from the outside of the tree and working your way to the inside of the tree to determine the amount of fruit damage.

While there may be a desire to do something right away to help your tree recover, the reality is we can’t do anything until the tree lets us know what damage it sustained and that may be a few months from now.

Fertilization:

The proper amount and timing to follow when fertilizing citrus is to give it small amounts throughout the growing season. Typically, this starts mid to late March. If your tree received cold damage, don’t change this timing, just reduce the amount. Roots and branches may have been damaged so your tree does not need to sustain as big of a tree as you had last year. For example, if 1/3 of your tree shows damage, reduce the amount of fertilizer by 1/3.

Irrigation:

If the soil is moist, the tree does not have to be watered. However, our dry season in March, April, and May will require supplemental irrigation of our citrus trees. If your tree starts to put on new growth, you may need to supply supplemental irrigation especially in the event of a dry spell.

Pruning:

Branch damage from the freeze may not be totally apparent until late spring or even early summer. Try and hold off pruning off the dead wood until then. As the tree forms new growth, you can then determine how far down the branch you will need to cut. Make the cut into green wood and if possible, remove the damaged branches at the branch collar. Any sprouting below the graft should be pruned off right away. This is the rootstock sprouting and any fruit produced by the rootstock will more than likely be poor quality.

A hard freeze is by far the most damaging event to occur in the life of our home grown citrus. With a little patience and a “wait and see” outlook, we may be able to care for our trees and bring them back to full recovery in a year or maybe two in the event of severe damage.

Article written by Larry Figart, Urban Forestry Agent, Program Coordinator, February 2023

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