In summer, an orange tree feels at home even in our latitudes. But you have to be well prepared for the winter. These tips will help you overwinter your orange tree.
Orange trees (Citrus x sinensis) originally come from the subtropical regions of China or Southeast Asia. Accordingly, they are not adapted to the cool temperatures in winter in this country. The citrus plant, which once arose from a cross between tangerine (Citrus reticulata) and pomelo (Citrus maxima), must therefore be overwintered in a frost-free place will. But how can orange trees be overwintered undamaged? We present everything you need to know about winter protection for the sensitive plant.
Holding the orange tree properly
In order to be able to overwinter in a frost-free room, you should plant your orange tree in a container that you can easily transport. Because orange trees can grow to an impressive size over time, sooner or later transport will only be possible with a sack truck or even heavier equipment.
At what temperature does it become critical for the orange tree?
Orange trees are not frost hardy due to their origin. So when does the orange tree have to go into winter quarters? In general, you should try to leave the orange outside for as long as possible. When the first night frosts are announced or temperatures are permanently below 5 °C, you should bring your orange tree to a sheltered place for the winter. When this happens depends on the region where you are cultivating your orange tree. But there can also be major differences from street to street: Unfortunately, gardens on the unprotected, wind-facing outskirts, in cool valley bottoms or at higher altitudes, for example, can hardly rely on the weather forecast. Therefore, when it comes to wintering, it is better to rely on your own experience.
Protect orange tree from cold
The easiest way to protect an orange tree from the cold in winter is to hibernate on onefrost-free place. It is not advisable to overwinter an orange tree outdoors as there is insufficient protection from frost. The best places to overwinter your orange tree are unheated conservatories or well-sealed greenhouses with frost guards. If this is not available to you, an unheated, bright staircase or an attic with many windows is also suitable. If temperatures drop below 5 °C in your room for a short time, it is advisable to wrap a coconut mat around the root ball.
Depending on the region, the orange tree can leave its winter quarters after the last frost in April or May.
Wintering the orange tree: the optimal conditions
Crucial for the selection of the winter quarters are both the temperature and the light conditions. The ideal winter temperature is between 5 and 10 °C. If the thermometer permanently falls below 5 °C, there is a risk of cold damage. If the temperatures rise above 15 °C, the hibernation is interrupted, which hinders the induction of flowering and thus the formation of flowers and fruit in the coming year. It is therefore not advisable to overwinter the orange tree in the living room or apartment.
The relationship between temperature and light is decisive for the successful overwintering of your orange tree. The higher the temperature, the more energy the tree needs and the more photosynthesis your orange tree has to do. Therefore, as the temperature increases, it needs more light. As light levels are often low in winter, we recommend aiming for a temperature around 5°C.
Tip: If the temperature and light supply are well adapted to each other, this offers the best conditions for a good overwintering. Orange trees that hibernate in a very cool place can also stand in a darker spot, while saplings that hibernate a little warmer need sufficient light.
Care for orange tree in winter
So that the orange tree survives the winter well, proper care in the winter quarters is also crucial.
Watering, repotting and cutting orange trees in winter
In winter you should keep the root ball of your orange tree slightly moist. But what does it exactly mean? In general, when overwintering orange trees, we recommend watering less than too much. It is best to wait until the upper quarter of the root ball has dried out before watering. At the latest when the first leaves start to curl up, you shouldpour.
You can use the winter time to repot your orange tree. Between February and March is the best time to plant the sapling in a slightly larger container. This is necessary about every three years. With regard to the demands on the soil and the planter, the orange tree is no different from other citrus trees. We therefore recommend our article on repotting a lemon tree for more tips.
In addition, spring, just before new shoots begin, is the ideal time to bring the crown of your orange tree back into shape. In general, orange trees should not be pruned regularly. If you want to cut your orange tree, you should only shorten individual shoots and avoid stepping back too much. However, dead shoots should be removed completely.
Fertilizing is not recommended in winter, as too much fertilizer could stimulate the plant to grow. However, this is undesirable during hibernation and is not beneficial for the plant in the long term. However, to ensure vigorous budding in the spring, you should ensure a good supply of nutrients after the hibernation. It is therefore advisable to start fertilizing about two weeks after you have brought the orange tree out of its winter quarters. Depending on the location, this is usually in April. This allows the plant to get used to the new location before fertilizing. Look for a predominantly organic fertilizer that is tailored to the needs of citrus fruits. Our Plantura organic citrus & Mediterranean fertilizer not only ensures that your orange tree is optimally supplied, but also helps to keep it he althy and resilient. The organic liquid fertilizer is also safe for pets and garden animals.
Orange tree loses leaves in winter: what to do?
Leaf loss often occurs on orange trees during the winter. The cause for this can be narrowed down based on the point in time: If the leaf loss occurs immediately after moving into the winter quarters, the temperature difference between the place outside and the winter quarters was probably too great. Then a partial loss of the blades has to be accepted, since switching again would cause additional stress. Leaf shedding should stop within a few days as the plant adjusts to the new conditions.
If the leaves start falling a few weeks after the orange tree has been placed in its winter quarters, it is most likely due to a lack of lightthe cause. We recommend that you look for a location that is as bright as possible or lower the temperature at the location, as the plant then gets by with less light. Alternatively, additional lighting with a plant lamp can ensure that light and temperature are again in a more suitable relationship.
If the leaves do not fall until February, this is often because the orange tree is exposed to direct sunlight. The plant evaporates more water than it can absorb with the still very cold roots. Removing the plant from direct sun should stop the leaf fall.
Pests in winter quarters
Pests are another challenge when overwintering orange trees. These are usually brought into the winter quarters with the plants and can then multiply quickly due to the lack of beneficial insects and good living conditions. Orange trees in the winter quarters are mainly attacked by lice and the red spider. In our special articles we have put together helpful tips for controlling scale insects, mealybugs and spider mites.
In general, it is better not to use synthetic pesticides on your orange trees, especially if you intend to harvest fruit from them. Our Plantura organic pest-free neem is an alternative based on natural raw materials that you can use in winter without hesitation. Many tried-and-tested home remedies also have a good effect. As a preventative measure, you should strictly check the plants before moving them to the winter quarters and treat them directly if necessary. It also makes sense to keep your orange tree over the winter at a temperature close to 5 °C to slow down the reproduction of pests.
At a glance: Caring for orange trees properly in winter
- Water when a quarter of the root ball is dry
- Repotting in February to March
- Reduce pruning to minimum
- Spring fertilization in April with a predominantly organic fertilizer
- Possible loss of leaves due to extreme temperature changes, lack of light or direct sun
- Check before wintering; Air temperature of about 5 °C reduces the reproduction of pests
- Natural pesticides or home remedies can be used to control pests
Are there hardy orange trees?
Orange trees (Citrusx sinensis L.) are generally not hardy. But if you are less concerned with the sweet fruit than with the Mediterranean look, there is actually an alternative for your garden: the three-leaf orange (Poncirus trifoliata), also called bitter orange. Three-leaf oranges can tolerate winter temperatures of below -18 °C, but unfortunately the fruits are very sour to bitter and therefore inedible. But it is definitely worth considering as a decorative tree in the garden.
We have compiled many more exciting tips and information about the orange tree in our special article.