GARDENER'S READING ROOM
Edibles
Indoor Plants
Trees & Shrubs

The Citrus in Winter

If your Improved Meyer Lemon doesn’t quite nestle on your coffee table, not to worry. You may be able to keep it outside year round!Here are some Citrus guidelines: Sweet oranges, grapefruit, Meyer lemon, and most mandarins and their hybrids are hardy to about 20 to 30 degrees. Kumquats, Satsuma mandarins, sour oranges and calamondin are hardy to temperatures in the high teens. Lemons (other than Meyers), limes and citrons are the most sensitive to freezes and should definitely come into your home or a green house for the winter. Any fruit, on any type of citrus, will be damaged by temperatures below freezing.Your plant will be more cold tolerant if placed on a nice sunny south facing wall, under an eave or some sort of cover throughout the growing season and then into winter. This allows your plant to tolerate a few more degrees of cold. In the fall, add a good layer of mulch as the root system is near the surface, water well, and hope that the weather goddess cooperates. It is important that we don’t get a freeze early in the season (like we did last November) so that the plant can acclimate to colder weather on its own terms. At our respective homes, we keep our plants in pots (potted in well-drained soil) so if the weather turns to severe cold (beyond what we know the plant will tolerate), we can take the plants into an unheated but protected area (such as a garage) until the weather begins to warm (usually a few days to a week at most). Of course, you can always take your plant in for the winter and put it in a nice sunny window away from any heat sources. Ideal humidity indoors is 50%. If you do take your plant in, do it by the end of October so it can have an adjustment period instead of going suddenly from the cold outside to the heat inside. Water citrus sparingly in winter. Note that leaf loss on citrus is common to some degree when changing its light and environmental conditions. We’ve seen plants lose all of their leaves and look like they were dead, but five or six weeks later they were in full leaf and a few weeks after that, flowers and then the beginning of fruit! So, if your plant looks dead, but you can still bend the branches, don’t throw it out.

By Mary Ann Greco and Cheryl Gere
Skylights Autumn 2007, Vol 22, No. 3

Other articles on edibles

Other articles on indoor plants

Other articles on trees & shrubs