The evergreen lemon tree with its creamy white, fragrant flowers and striking yellow fruits originally comes from the subtropical regions at the foot of the Himalayan Mountains. However, the plant has been native to the Mediterranean region since ancient times, as traders brought it from Asia via Greece to Italy over 2000 years ago. Lemons are quite easy to grow from the seeds inside, but caring for them is a little more difficult - especially in winter.
How to properly care for a lemon tree?
Caring for a lemon tree includes regular watering without waterlogging, plenty of light, cool wintering, annual repotting, fertilizing with citrus or complete fertilizer and, if necessary, a topiary. Protect the tree from diseases, pests and frost.
Does a lemon tree need a lot of water?
As subtropical plants, lemons need regular watering. Regular watering, daily on sunny days, ensures good growth. However, the plants cannot tolerate having their roots permanently submerged in water. Plant pots and deep saucers should therefore be checked regularly for residual water. The right time for watering has come when the surface of the substrate has already dried.
Can you plant a lemon tree in the garden?
In Central and Northern European climates, it is not advisable to plant the lemon tree in the garden. The lemon can tolerate temperatures as low as minus 4 °C for a short time, but not in the long term. In addition, the roots are extremely sensitive to frost (unless they are grafted), and the lighting conditions in winter are far from sufficient. In short: it's too cold, too windy, too wet and far too uncomfortable outside for the lemon. In summer, however, it likes to stand in a pot in the blazing sun.
Is the lemon tree frost hardy?
No. However, lemons grafted onto bitter lemons or bitter oranges are much less sensitive to unfavorable weather conditions.
Is a lemon tree suitable as a pure houseplant?
Although a lemon tree can be kept indoors all year round, this attitude is not optimal. Lemons need a lot of light - not only in summer but also in winter, which is why indoor lemons should be irradiated with an extra plant lamp. However, lemons overwinter best in a cool place.
When and how should a lemon tree best be repotted?
Young plants are repotted once a year, older trees about every two to three years. At best, the new planter is about a third larger than the root ball. The best time to repot is at the beginning of the growing season.
What kind of fertilizer does a lemon tree need?
Lemons are best fed with a citrus fertilizer (€6.00 on Amazon) or with a liquid complete fertilizer (which contains nitrogen, phosphorus and potassium in a ratio of 3:1:2).
When and how should you fertilize?
In the growing season between March and September, the lemon tree should be fertilized about every two to three weeks. Mix the fertilizer with the irrigation water and then water the tree as usual.
Does a lemon tree need to be pruned?
In nature, a lemon tree can grow up to six meters high, and the plant also grows quite quickly. It is therefore advisable to carry out regular topiary trimming before moving into winter quarters.
How do you overwinter a lemon tree?
Lemon trees should overwinter in a bright and cool place, such as an unheated or slightly heated room. Overwintering in a winter garden is ideal. Above all, you should pay attention to sufficient light; ideally, you should install an additional plant lamp. In winter there is little watering and no fertilization at all.
Diseases of the lemon tree and their treatment
If the leaves of the lemon tree turn yellow, become pale or even fall off completely, there is often a lack of nutrients, light and / or water. But root rot as a result of waterlogging can also be the cause.
How do I know if my lemon tree is infected with pests or fungi?
You can often recognize a pest infestation by discolored or falling leaves and by the fact that the lemon tree sticks. If the leaves and/or shoots are covered in black, the tree is infected with a sooty mold fungus. This can simply be washed off. Lemons are very susceptible to infestation with spider mites and plant lice, especially in connection with improper overwintering.
What can I do against a pest or fungal infestation?
Plant lice can be controlled with soapy water or a mineral oil spray. If the infestation is large, you can put the pot and the substrate in a plastic bag and dip the tree upside down in a bucket of soapy water. The treatment should be carried out several times, a few days apart. Fungi are effectively controlled with a fungicide.
My lemon tree has thorns. Is this normal?
Yes, many lemon trees - especially those that you have grown yourself from seeds - have occasional thorns on the leaf axils that can be up to five centimeters long. The downy hairiness of young branches is also normal.
Tips & Tricks
Usually every flower develops into a fruit. So that the tree is not overwhelmed with the supply of small lemons, you should thin out the fruit. This allows the remaining ones to grow better and reach maturity.
