Hopefully there is still some fruit on your trees to enjoy during the holidays. If traveling to visit friends and relatives during the holidays, it is a good idea to bring a box of citrus for them to enjoy. Most of the citrus we grow should now be ripe and ready to eat! Depending on the variety all satsumas should have been ripe enough to eat in mid October to mid November. There are some varieties of oranges that will not ripen until January and February but most people have the navel oranges or the Louisiana sweet oranges, which ripen in

late November to December. Grapefruits usually do not ripen until December. You need to enjoy the fresh citrus while you can because before you know it all of the home raised citrus will be gone, and we will have to wait another year for the next crop.

It is important to not leave the fruit on the trees for too long. The citrus tree needs time to rest before it blooms and starts producing another crop. Make sure that during the month of January the fruit on your tree has been eaten or removed from the tree. Citrus will stay fresh in the refrigerator for three to four weeks or more.

Remember that if we get severe cold weather you may have to protect your tree. Louisiana generally has its coldest temperatures in late December, January and early February, and protection of citrus trees becomes important to homeowners across the state. It is difficult to pinpoint a temperature at which it becomes necessary to protect citrus trees because the temperature tolerance of the citrus trees varies among the different species. Satsuma and kumquat trees usually do not need protection until the temperature drops below 20 degrees F. Oranges are usually OK until around 22 degrees F. Lemons, limes and grapefruit may need to be protected when the temperature dips below 26 degrees F. However, theses trees can be killed or damaged at higher temperatures if they are not sufficiently hardened with enough preconditioning cold temperatures or if the tree was not properly cared for going into the winter.

Also, a citrus tree increases in cold hardiness as it gets older, but an older, unhealthy tree can still be very susceptible to the cold. The duration of the sub-freezing temperature is also very significant. If the temperature is below the threshold for the specific species for more than 6 -8 hours, some damage to trees as well as some dead trees may be expected.

The best way to lessen cold damage to citrus is to maintain healthy trees. Follow the recommended spray schedule to control insects and diseases. Clean mechanically or use a herbicide to control weeds and grass around the base of the tree. Grass, weeds and straw mulches prevent heat from entering the soil during the day; therefore, less energy is stored for release at night. Banking the trunks of young trees with soil and wrapping the trunks of the trees with some type of insulation will help prevent cold damage to trunks and root systems. Although tree tops may still be lost during freezes, a tree can recover about 80 percent of its growth the first year if its trunk and root system are intact. Also, trees should be watered thoroughly before the severe cold since trees are damaged because they actually dry out from the severe cold. Fertilizer should not be applied to citrus trees until late mid to late February.

To protect a single tree, home gardeners can construct a frame over tree and encase the tree in translucent plastic with one or two layers. In our areas, such an extreme practice would be needed only on a few severely cold nights and cloudy days. Incandescent light bulbs can raise the temperature in the frame a few degrees. Fresh air is a must for such frames, and air temperatures within should not be allowed to go above 85 degrees to 90 degrees F. Venting should be provided to make it easy to maintain a constant supply of fresh air and to control temperature. Care should be taken to prevent the bulb from coming in contact with the plastic wrap. Many trees are damaged more severely because homeowners fail to remove the covering after the dangerous cold and the extreme heat from the light bulb may dry the tree out. Generally these coverings can usually be removed once the sun rises in the morning.

If your tree suffers from cold damage, wait until the early spring to determine if the entire tree is dead. Some trees may still sprout out above the graft and grow back when you think they have been killed. Any limbs that break easily when bent are dead and can be removed. Limbs that bend but don’t break are still alive. Anything sprouting above the graft is good.

For further information about citrus you can purchase the Louisiana Home Citrus Production bulletin, publication No. 1234 for $5 at your local LSU Ag Center Office, or you can order it on the web at www.lsuagcenter.com. You may also contact your local LSU Ag Center county agent.

If you have any questions, please contact your local LSU Ag Center County Agent. You can contact David Pichon, County Agent-St. John Parish at 985-497-3261 or by email at dpichon@agctr.lsu.edu.