Citrus trees are evergreen plants that we all love! Many gardeners grow lemon trees in the garden or indoors. A lemon tree may lose leaves if it is stressed. There are a few causes for this problem, but fortunately there are also the corresponding solutions. Read on to learn how to save your lemon tree and how to properly care for it.
Lemon tree loses leaves due to cold damage
As a general rule, citrus trees do not like cold or frosty temperatures. Winter lemon tree leaf drop can happen when temperatures drop to minus 2 degrees Celsius for four hours or more. When temperatures drop below 0 degrees Celsius, it is best to protect young trees (under five years old) by covering them or moving them to a sheltered location.
If possible, water the plant 48 hours before frost and postpone pruning until spring to prevent winter leaf fall.
You can find more useful tips regarding winter storage in the article “Cut the lemon tree and overwinter it - this way it won't lose any leaves
Overwatering can cause leaf drop
Your lemon tree is losing leaves due to overwatering and this is a common reason for leaf drop. If the tree's roots are in water, they can develop root rot, which in turn causes the lemon tree to drop leaves.Mulcharound the roots to help prevent root rot and keep watering to a minimum.
Avoid dehydration
Leaf fall can also be due to a lack of moisture. If the leaves are shriveled before falling, this is an indication that the lemon tree is under stress due to drought. Lemon trees prefer to be watered relatively infrequently, but with insufficient watering you may suffer from leaf drop. Lemon trees need to be watered generously so that the water seeps into the bottom of the pot.
Dry climates, excessive wind, or dry air when the lemon tree is indoors also deprive the leaves of moisture, causing them to fall off. Intense heat in a greenhouse, near a heat source, or due to weather conditions can increase the rate of soil drying and deprive the lemon tree of moisture, again causing leaf drop.
Lemon trees lose leaves due to lack of sun
Lemon trees like the sun. Leaf fall can therefore occur if the lemon tree is in the shade. Then the leaves may turn yellow and fall off, and the plant looks unhealthy. Placeyour lemon treealways as sunny as possible, be it in the garden, in the greenhouse or in the house in winter.
If you bring your tree indoors in the winter, be sure to place it in a south-facing, sunny window to keep it healthy and to meet its sunlight needs and prevent leaf drop.
Lack of nutrients is another cause
A deficiency in any of the nutrients that lemon trees need to thrive can lead to problems such as leaf drop. In particular, nitrogen, magnesium, iron, zinc and manganese deficiencies can lead to leaf droplead to lemon trees. To maintain healthy trees, fertilize with a good citrus fertilizer every six weeks if the tree is younger than seven years. Mature trees should be fertilized frequently but in small amounts from October to February.
Lemon tree loses leaves due to foliar diseases
Some lemon leaf diseases that cause yellowing, dieback and defoliation are: Alternaria brown spot, fat spot and Phytophthora.Alternaria brown spot diseaseleads to yellowing of the leaves and blackening of the leaf veins and to fruits with sunken black to brown spots with yellow halos.Die Grease spot diseaseis caused by fungal spores andcauses yellow spotson the top of the leaf. Leaf drop then occurs, reducing fruit set and increasing the risk of damage to the tree from cold or pests. Improving drainage and morning watering will help eliminate Phytophthora, as will keeping the area around the tree clear of grass, weeds, other debris and mulch.
Watch out for pests
Pests can also be responsible for leaf fall on the lemon tree.The Asian citrus pyllidproduces honeydew, which leads to sooty mold and causes damage and leaf fall by eating the young citrus leaves. Oil sprays can control this pest if used frequently.The citrus leaf mineris also a pest that attacks the leaves of citrus trees. The leaf miners are hardly visible to the naked eye. Infected areas of the tree should be removed and destroyed so that the control of the insects is successful. The introduction of a predatory wasp has also proven to be a successful means of controlling the leaf miner population.
Lack of fertilizer can cause leaf fall
Lemon trees are heavy feeders and require regular fertilization. While a lack of fertilizer is usually not a direct primary cause of leaf drop, it is often a contributing factor. Lemon trees thrive in pots because they have good drainage and in cooler climates they can be brought indoors for winter protection. However, the roots can deplete the nutrients in the pot, causing the leaves to turn yellow and some of them may fall off.
Experts recommend using a special citrus fertilizer, available at garden centers, once a month during the growing season to promote fruit production and ensure the plant stays healthy in the cold, making it more resilient and reducing the likelihood of it dying leaf fall suffers.
Repotting a lemon tree and cutting the roots - instructions on when and how to do it rightyou can find here!
