The walnut tree is one of the oldest known tree species. Almost all parts as well as the nuts are the purest garden pharmacy. In addition, its tannin-rich leaves can keep unloved insects away. For most, however, the nuts are the main argument in favor of planting a walnut tree. In terms of height, a distinction is made between large and small varieties. But how powerful can such a tree actually get?
Heights of growth of walnut trees
The real walnut (Juglans regia) is a deciduous, spreading and fast growing tree. In the course of its life, under favorable conditions, it can take on stately proportions, both in height and in width of the crown.
- Walnuts can reach heights of 25-30 m
- Trunk develops, depending on the variety, a diameter of up to 200 cm
- The broad, round crown can take on dimensions between 10 and 15 m
- Walnut develops deep tap roots
- The root system is also noticeably wider
- The dimensions of the root can exceed those of the crown
If you want to plant a walnut tree, you should plan an area of 70 to 120 m2, depending on the variety, even if it appears relatively thin at first. There are now also varieties that are much smaller in growth and are therefore also suitable for smaller gardens and sometimes even for larger pots.
Dwarf varieties are much smaller
In contrast to the usual stately walnut trees with their imposing shape, dwarf varieties grow more slowly and more compactly. They stay significantly smaller and their crown is down
Tip: Good small-stature varieties are z. B. the Weinsberg walnut, the bush nut from Finkenwerder and the varieties Lara, Europa, Dwarf Karlik (R) and Mini Multiflora No. 14.
Average growth per year
- Noticeable differences between seedling plants and cultivars
- Seedlings raised from nuts grew more slowly
- Only slight growth noticeable in the first and second year
- From the third year onwards, the growth rate increases significantly
- It is now between one and two meters per year
- Growth rate for cultivars, depending on the respective variety
- Early and richly bearing ones grow rather slowly
- Others have an annual growth rate between 50 and 100 cm
- The biggest increase happens between the 10th and 30. Standing year
- This is the time when the walnut tree grows fastest
Later growth slows down again and focuses mainly on the growth of the crown and the development of the fruits. From around the age of 40 Year the crown growth decreases again. At around 70 to 80 years of age, the increase in height is complete. As a rule, the yields then also decrease somewhat. With short stature or For dwarf varieties, the annual growth rate is between 10 and 20 cm.
Tip: A walnut tree grown as a seedling bears fruit for the first time after 10-15 years at the earliest, whereas cultivars already bear fruit after four
up to six years.Factors Affecting Growth
How tall a walnut tree can ultimately get depends on various factors. Both the variety and the age of the tree as well as the trunk circumference, the nature of the soil and the stand density can influence the growth behavior of the walnut tree positively or negatively.
Variety-dependent growth heights
How big a walnut tree ultimately becomes and how long it takes can vary greatly from variety to variety. There are small varieties such as the 'nut from Chatenay' with a stature height of up to four meters and medium-high walnut varieties such as. B. Juglans regia 'Weinsberg 1', the stature heights of approx. can reach seven meters. Both are good for smaller areas in the garden. In contrast, there are medium-strong growing specimens such as the 'Rote Donaunuss', which can grow up to 12 m in height grows and vigorous ones such as the Kurmarker Walnut (No. 1247), which sprouts early, with sizes between 15 and 25 m.
Age of the tree
- The age of the tree has a major impact on its growth
- In the first few years it grew rather irregularly and sparsely
- As a rule, growth is not even 20 cm per year
- Is usually even far below
- In the following years he easily gained between one and two meters
- Growth from the 10th Year of standing more even and constant
- Now grows between 50 and 100 cm per year
- Baum has approx. 80 years ago it reached its maximum height and width
Trunk circumference
The respective trunk diameter also has an influence on the growth of these trees. Responsible for this are the so-called vascular bundles, which run in the bark and supply the tree with water and nutrients through the capillary effect. The more space these vascular bundles have, the better the tree is supplied, which in turn promotes growth in height and width. In older specimens, from a height of around 25 m, this capillary effect is usually no longer sufficient, growth stagnates and the tree has reached its maximum size.
Condition of the soil
Another factor influencing growth is the nature of the soil. For example, if the tree is on poorly ventilated soil that is prone to waterlogging or is too sandy, this can affect its growth. It grows more slowly and fruiting also suffers. In contrast, a lime-rich loam or clay soil can lead to optimal growth conditions and
Contribute income. In general, the walnut tree feels most comfortable on acidic to neutral soils. Soils with an alkaline pH are also tolerated.Population density
The height this tree can reach also depends on whether it stands alone or in a stand of several trees. Solitary specimens usually do not grow taller than 20 m, while trees in the middle of a dense stand can grow up to 30 m in height. This is due to the fact that in denser stands they literally push themselves up towards the light and can therefore become larger. However, this only affects the growth in height and not the growth in width of the crown, which is then usually less.
Special features of the cut
Pruning measures for the walnut are actually only called for when it has grown too sprawling and takes up too much space. The aim of pruning measures should always be to maintain the tree's typical shape. The most important thing here is the right time to cut. It is in late summer or August September. During these two months the flow of sap is very weak as the tree is preparing for hibernation. In addition, the cuts can heal before winter, at least the smaller ones. If this point in time has been missed, for whatever reason, a winter cut is also possible from mid-December to mid-January. This late cut has the advantage that the walnut then no longer bleeds because the flow of juice has come to a standstill.
Thin out or shorten?
The walnut tree reacts to the shortening of individual side shoots with a stronger shoot. If you don't want that, you'd better make a clearing cut. This gives the tree the opportunity to develop a loose crown over the next few years. If the crown is too powerful or too expansive, a clearing cut is usually not sufficient, so that the outer shoots have to be shortened.
- When cutting out a few crown branches cut out to the trunk
- To reduce the diameter of the crown, shorten the shoots
- Cut back every second shoot in the first year
- Up to the height of a fork, by a maximum of 150 cm
- The next year, cut back the remaining shoots
- Also remove sick and dead wood
- Avoid cutting measures in early spring
- The flow of sap is strongest at this time
- Tree would be weakened but not die