Large-scale leaf drop indicates that something is wrong with the evergreen lemon tree. Then you should quickly check the conditions of cultivation to save the citrus plant.
Lemon trees are one of the great favorites among exotics, because the tropical plant bears fragrant flowers and fruits even in temperate climates. Unfortunately, however, Citrus limon is not entirely uncomplicated when it comes to caring for it as a potted plant. Mistakes in care are usually indicated by the lemon tree losing its leaves, and then you have to act quickly, because the tolerance to incorrect treatment or unfavorable locations is not very high. If your lemon tree suddenly loses most of its leaves, you should ask yourself the following questions and check the possible causes.
Why does the lemon tree lose leaves?
Is your lemon tree too dry?
If the lemon tree loses masses of leaves, it is necessary to check whether perhaps something is wrong with the water supply. If you water the citrus plant too little overall, the leaves curl up, hang limply on the tree and eventually fall off. When caring for the lemon tree, make sure that the water supply is even, because the exotic fruit also does not like too long watering intervals. A continuous alternation between flooding and drought, the lemon tree can not compensate well.
So always water enough so that the root ball is well moistened without waterlogging, and repeat the watering process as soon as the top layer of soil has dried. Lemon trees need a lot of water. If you have a sunny spot on the patio, a small tree can tolerate daily watering in the summer. Also, when wintering the lemon tree, be sure to supply it as needed, rather than following a set weekly rhythm when watering.
Is wetness the cause of leaf drop?
The same problem that the lemon tree has with dryness, it also has with waterlogging. If you have overwatered your tree and the root ball is in wet soil for days, Citrus limon will also react by dropping leaves. In addition, the tips of the young shoots will die. If you notice that the root ball of the lemon tree is still wet days after watering, repot the plant as soon as possible into dry substrate. Also, at planting time, add a drainage layer of expanded clay or grit to the bottom of the pot so that the risk of water pooling is reduced in the future. Overflowing water in the saucer should be emptied daily.
Does the lemon tree lose its leaves in the winter quarters?
The lemon tree often loses its leaves if it is exposed to large temperature fluctuations during the winter or if the temperature difference between the roots and the crown is too big. If the roots are cold, for example, on a stone floor, but the crown is exposed to sunlight, for example, in a glass house or through a window, the tree does not know whether to rest or grow, and leaf fall is the result.
Therefore, make sure that the wintering of your lemon tree is either in a cold ( 3 to 10° C / 37 to 50 °F) and dark or shaded quarters, or in a bright and warm (above 20 °C / 68 ° F). Low humidity in the winter quarters will also cause the lemon to lose its leaves. With leaf fall in the winter quarters evergreen lemon tree, unlike deciduous native woody plants, always indicates stress, so in this case you should act quickly and check the location and care.
Did you replace the plant in a new location?
Moving a plant from one place to another often results in leaf drop. This can happen as soon as you move the lemon tree from one room to another, bring it home from the store, or bring it to winter quarters in the fall. The change in light levels, humidity and temperature will be hard on the plant and it will take some time to get used to the new situation.
If you overwinter the lemon tree in a bright and warm room, bring it into the winter quarters a little earlier, before the outside temperatures drop too much. Otherwise, the change from cool outside in the fall and warm indoors will cause rapid leaf drop shortly after the move. A generally too dark location also causes leaf drop in the lemon tree. A change of location or a plant lamp will remedy this.
Is there a pest infestation?
If pests such as spider mites or scale insects are the reason for leaf drop on the lemon, you can usually tell by taking a closer look at the tree. Spider mites are very small, but their woolly webs between the leaf axils are easily visible. Scale insects show up as small green-brown bumps on leaves and twigs. Aphids can also appear in large numbers in the summer and become a nuisance; more rarely, mealybugs are found on the citrus plant. Regularly check the lemon tree for pests, especially in the winter quarters, because they particularly like to settle on the plants in dry air.
What to do when the leaves fall off the lemon tree?
If the lemon tree, for whatever reason, has already lost quite a few leaves, reduce the watering and temporarily stop fertilizing the citrus plant. Due to the significantly reduced leaf mass, the tree’s water and nutrient requirements drop significantly, so that waterlogging can now quickly occur in the pot. Even if drought was the reason for the leaf fall, you should slowly care for the tree healthy and increase the amount of watering step by step, so as not to drown the lemon after a prolonged dry period.