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Lemon tree has yellow leaves: possible causes and tips for care for brown spots, discoloration and loss of leaves.

With its evergreen foliage, filigree light pink flowers and fragrant fruits, the lemon tree is one of the most popular potted plants in Germany. The citrus plant pleases the eye all year round with its wintergreen fragrant leaves and is a real eye-catcher both in summer and winter. However, it is all the more annoying when it suddenly loses its foliage. An ailing lemon tree has yellow leaves that fall off. But what could be the cause? We list the possible causes and provide useful care tips.

The lemon tree has yellow leaves: causes and care tips

Lemon tree has yellow leaves possible causes

It often happens: the lemon tree suddenly gets yellow leaves. This is an important indication for experienced amateur gardeners that the citrus plant lacks nutrients or that it cannot process the nutrients properly. But this undersupply could have several reasons: Diseases, pests and care mistakes such as incorrect watering or fertilizing. Sometimes this phenomenon is seasonal. For example, plants suffer more often from waterlogging in winter quarters than outdoors.

Should you remove the yellow leaves? If the tree is diseased or infested with pests, then you should remove the leaves. Also cut off wilted leaves, because they are entry points for bacteria and fungi and weaken the citrus tree. If the foliage has turned yellow due to lack of nutrients or water, then you can simply leave the leaves on the tree.

Iron deficiency or magnesium deficiency

Lemon tree magnesium deficiency yellow leaves green veins

Possible cause iron deficiency: if the lemon tree gets yellow leaves, then this indicates iron deficiency. The symptoms of chlorosis can be quickly identified: First, the new leaves and young shoots change color. The edge of the leaf turns light yellow, then gradually the whole leaf discolors.

Care tips:

1. fertilize the lemon tree properly: In spring and summer, fertilize with special fertilizer for citrus plants once a week. Especially potted plants often suffer from chlorosis – the watering and rainwater wash away the nutrients from the soil over time. Therefore, regular applications of fertilizer are an absolute must.

2. repot every three years (from April to July, possible until late summer if necessary). Low soil volume can be another reason for chlorosis.

3. water properly with decalcified water: High levels of lime in the soil can prevent uptake from the iron. To be on the safe side, also check the pH of the soil.

Lemon tree has yellow leaves in summer and winter

Possible Cause Magnesium Deficiency: When there is a magnesium deficiency, the lemon tree develops yellow leaves with green veins. Unlike iron deficiency, the old leaves turn yellow from the outside in first.

Care tips:

1. fertilize lemon tree properly: Do not use nitrogen-rich fertilizers for the citrus tree. Instead, take special fertilizer for citrus trees and add magnesium preparation to the water. You can also use algal lime.

2. loosen the soil: a loamy, heavy soil is a great challenge for the citrus tree. The woody plant cannot root properly and absorb the nutrients.

Are the leaves yellow and curled up? Drought stress

Lemon tree has yellow leaves curled up because of drought

Possible cause Drought: Especially in summer, when it rains less and the water in the container evaporates faster, the tree is sensitive to longer periods of drought and gets into drought stress. The leaves curl up so that they evaporate less water. If they also turn yellow, then you should act quickly.

Care tips:

1. water abundantly: If the leaves are only curled, it is sufficient to water the tree more frequently than usual over the next few weeks. You can slowly increase the amount of watering.

2. immerse roots in water: If the leaves are curled and yellow, you can fill a bucket with lukewarm, decalcified water. Remove the tree from the bucket, carefully loosen the soil from the roots and immerse them in the bucket. Leave the tree in the water for a few minutes, allowing the roots to soak. When you no longer see air bubbles on the surface, then you can remove the tree from the water and plant it in the tub (preferably with new moist soil).

Lemon tree has yellow leaves and brown spots: diseases.

Lemon tree gets yellow leaves possible causes

Diseases as possible causes: Yellow leaves and brown spots usually indicate a leaf spot disease such as star sooty mold. If bacteria and fungi are affecting the plant, then quick action is needed.

Care Tip:

1. cut off all diseased parts of the plant and dispose of them with household waste.

2. it is best to bring a leaf to the garden center, so you can quickly see what the problem is. Depending on whether it is bacteria or fungus, you can find the appropriate remedy and treat the plant with it.

Yellow leaves in summer and winter: Wrong watering

Lemon tree loses leaves turn yellow in summer

Often, the yellow leaves on the lemon tree are due to a care error. These are often seasonal.

The lemon tree has yellow leaves in the summer: usually the tree is not watered enough.

However, if the citrus tree has yellow leaves in winter, it is usually due to waterlogging. You watered it too much, the moisture in the soil can not evaporate quickly enough and the fine roots begin to rot.

How often should you water a lemon tree?

As a rule of thumb, never let the soil dry out in the summer; it should always be moderately fresh to moist. Water the lemon tree twice a week.  In winter, you can water the exotic less often and less. It is enough if you water it once a week.

The yellow leaves will fall off: Temperature fluctuations

Lemon tree has lost all leaves how to save

In most cases, the lemon tree can recover quickly and the leaves will either turn green again or the exotic will gradually form new green leaves and replace the diseased ones.

However, if within a few weeks the leaves turn yellow and immediately fall off, then you should quickly find the reason. Often it is due to drought stress in combination with temperature fluctuations. The citrus tree is very sensitive to low humidity in summer.

Why does my lemon tree have such light leaves after repotting?

If the leaves of the lemon tree turn light green after repotting, it is usually due to stress. Another possible cause of pale leaves is nutrient deficiency. This can be eliminated by regular fertilizing.

My lemon tree loses all its leaves: Cut it back?

Lemon tree loses all leaves cut back

Is a lemon tree without leaves even salvageable? Fortunately, yes. A change of location, temperature fluctuations and heat can stress it. The result: the leaves fall off . However, if the tree loses all its leaves, then for the first time you should reduce the amount of fertilizer and water accordingly. After all, the fewer leaves the lemon tree has, the less water and nutrients it needs. If you continue to water it abundantly, the excess moisture will not evaporate and the roots will rot.

Pruning is not recommended and can put additional stress on the tree. If it needs a nurturing pruning, it is best to do it in the spring.