The strawberry tree, Arbutus unedo, is generally not hardy. Leaving it outside during the cold season is therefore not a good idea. Ice and snow can quickly cause significant damage. However, overwintering outdoors may still be possible. This depends on the respective variety, the specific location and the age of the tree. The trade in Central Europe now carries breeds that can survive outdoors at temperatures down to minus 15 degrees Celsius. In Spain or Portugal this is usually not a problem. However, German winters are significantly colder on average.
The location question
In Germany, winters also differ considerably from region to region. In other words: In order to determine whether the tree will survive a winter outdoors, you need to know exactly which hardiness zone you live in. In addition, the so-called microclimate in the garden plays a role that should not be underestimated. In general, however, it can be said that even for supposedly hardy strawberry trees, only very few areas in Germany are suitable for overwintering outdoors.
Age
The age of the tree is also important in this context. The following applies: Young or relatively young strawberry trees are definitely not suitable for overwintering in the garden. They are not hardy under any circumstances. However, things are different with trees whose wood is already well matured and which therefore have a few years under their belt. Unfortunately, it is not possible to give precise information about the age at which one can consider overwintering outdoors, as plants generally develop differently.
Safe site
By now it must have become clear that leaving a strawberry tree outdoors is a very uncertain matter. In any case, there is a very high risk that he will suffer significant damage as a result. It is therefore advisable to play it safe. And that means that the tree does not overwinter in the garden, but rather moves into winter quarters where it can be kept safe from frost and snow.
Wintering in winter quarters
In principle, all closed rooms are suitable for overwintering a strawberry tree. Of course, it goes without saying that these must meet certain requirements. The most important requirements are:
- Temperatures in the range of three to eight degrees Celsius
- dry room
- possible incidence of light (window)
- Possibility of ventilation
Winter gardens have proven to be ideal winter quarters for strawberry trees. They bring everything you need to ensure that the tree survives the cold season safely. If you don't have a winter garden, cellar rooms or stairwells, for example, are ideal. They should definitely meet the above requirements and must under no circumstances be heated.
Wintering specifically
The strawberry tree is moved to its winter quarters in early autumn. The ideal time for this is usually early to mid-October. This is the best way to rule out the possibility that the tree will be damaged by the first night frosts. Of course it remains in its planter. It inevitably follows that he was also housed there outdoors. A tree planted in the garden can in principle be dug up and overwintered. However, there are greater risks. Under no circumstances should a tree that has been dug up be placed in a planter for the winter. It promises more success to completely enclose the root ball and soil with a fleece.
Lots of peace
You will do your strawberry tree the greatest favor if you leave it largely alone in its winter quarters. It is already too late for any care or pruning measures. If necessary, you should water the plant a little now and then. But be careful: too much water is harmful. A few splashes of water are enough. After all, the plant is in a resting phase and therefore requires very little liquid. You can and must avoid giving fertilizer completely. In the worst case, it can even be counterproductive.
Ventilation and temperature
When overwintering, it is important to ensure that the temperatures in the room do not rise above eight degrees Celsius. For example, if it is necessary to heat the stairwell or basement because the outside temperature is too cold, only a change of location will help. In general, regular temperature checks are recommended. And a supply of fresh air can't hurt either. However, the room should only be ventilated briefly and only when there are no arctic conditions outside. Air that is too cold can damage the plant. By the way, it shouldn't be left directly in a draft - regardless of the temperature outside.
After wintering
When winter comes to an end and spring is on the horizon, Arbutus unedo must slowly get used to the higher temperatures and larger amounts of light again. From around February, but no later than March, he should move from his winter quarters to a window on the south side of the apartment. With the move you can also start watering the tree a little more. The amount of water should be slowly increased step by step. From March or April, the strawberry tree can be left outside for an hour a day - either directly in the garden or on the balcony. This time period is also increased step by step. To be on the safe side, however, he should not spend the nights outdoors until around mid-May, as night frosts can still threaten.
