Every child knows: In autumn the leaves change color and fall off. The trees are bare in winter, only to sprout again in spring. Only conifers remain green even in winter. However, there are even more trees that do not lose leaves - they are an important stylistic element in garden design.
Which trees don’t lose leaves?
Trees that do not lose leaves are mostly conifers such as spruces and firs, but also evergreen deciduous trees such as boxwood. Semi-evergreens such as akebia and privet retain their foliage during mild winters, while wintergreen trees such as hornbeam and oak retain their dried leaves until spring.
Why deciduous trees shed their leaves in autumn - and conifers don't
If deciduous trees kept their often large and thin leaves over the winter, they would freeze to death in the event of frost. The sensitive foliage has no protection from frost, but must be supplied with water and nutrients by the tree. Basically, the autumn leaf fall serves to protect the tree: if it kept its leaves, it would neither be able to feed them nor protect them from the cold and would therefore inevitably be damaged. Instead, it extracts the nutrients from the leaves - which is why the foliage changes color - and then throws them off. Conifers, on the other hand, have developed a different strategy: their leaves, the needles, are very small and also surrounded by a protective wax layer. Therefore, they cannot freeze to death in winter and remain on the tree.
Which trees don’t lose leaves?
Most conifers, with the exception of the European larch, are evergreen. There are also evergreen deciduous trees that you can recognize by their very small, thick leaves. A typical example is the boxwood. However, there are other variants in which trees retain their leaves in winter.
Evergreen trees
Evergreen trees keep their leaves all year round and only replace old leaves. Depending on the tree species, the leaves stay on the tree for between three and ten years. In addition to the conifers, there are a few evergreen deciduous trees, although these are not trees. For example, periwinkles are:
- Bamboo (Nandina domestica)
- Cherry laurel (Prunus laurocerasus)
- Firethorn (Pyracantha)
- Holly (Ilex)
- Boxwood (Buxus sempervirens)
Semi-evergreen plants
Semi-evergreens are trees that remain green in mild winters and only shed their leaves in very frosty temperatures. This group includes, for example, the akebia (Akebia quinata, also climbing cucumber) and the oval-leaved privet (Ligustrum ovalifolium). These species are not trees either, but rather a climbing plant and a hedge plant.
Wintergreen trees
Wintergreen plants, on the other hand, retain their leaves (which are often dried out and therefore brown from autumn onwards) and only throw them out when the new leaves emerge in spring. This group includes some native deciduous trees such as the hornbeam, the oak or the common beech.
Tip
Bamboo can grow to be several meters high and is often used for hedge planting, but botanically it is considered a grass and not a tree.
