Should citrus fruits be brought in before winter? The response from Maryse Friot, President of the Société d’Horticulture de Touraine.
Citrus fruits are Mediterranean plants which do not have the same hardiness. Thus, some lemon trees have a hardiness of between – 2 and – 5°C but others go down to – 8°C. The orange tree can go down to -5 or even -7°C, while the Poncirus Trifoliata with its very long thorns is very hardy. In fact, citrus fruits can withstand cool temperatures for short periods of time, but they fear long-lasting cold.
The ideal, in the fall, is to bring them under a veranda, an unheated greenhouse or other frost-free shelter. Currently, it is still too mild to bring them in. The place must be bright, displaying temperatures between 8 and 10°C, that is to say relatively cool.
Inside the house or apartment, the air is too dry and too warm for the winter. The garage, the garden shed lack light and often present a risk of frost.
If it is not possible to return them, you can leave the citrus fruits outside if the temperatures do not drop below -5 C°. It will only be necessary, under this temperature, to protect them with a wintering veil provided that the veil is not in contact with the leaves.
Pot, the root system is very exposed to the cold. The pots must be packed close together and the pots wrapped in straw or veil. This situation is very specific and requires frequent monitoring as well as ventilation.
Reduce watering (in general, two waterings per month are enough) and stop adding fertilizer throughout this period. The citrus fruits are then at rest.