Interesting facts about the root of the walnut tree

Interesting facts about the root of the walnut tree

Walnut tree is taproot

The walnut is deep-rooted with taproot. This means:

  • The root of the walnut tree penetrates deep into the earth.
  • She does this like a stake.

also read

  • Age of the walnut tree - how many years can it live?
  • Practical tips for caring for the walnut tree
  • Interesting facts about the walnut tree's heyday

Here is a general definition of the taproot: It is a root that develops from the germinal to the main root and grows vertically into the ground (into the earth). Side roots of the first order arise from the tap root. These go obliquely or horizontally from the tap root.

The taproot is therefore part of a heterogeneous root system. In technical jargon one speaks of allorhizia.

Note: The taproot in the walnut tree is extremely well developed. It clearly exceeds the lateral roots in terms of length and diameter.

Excursus: characteristics of shallow roots

To understand the difference between deep and shallow roots, here is a brief explanation of the latter:

A shallow root is always a plant (such as a tree ...) with roots that do not dig very deep into the earth. The exact opposite is true. The roots spread out like a plate in the upper soil layers.

Examples of shallow roots:

  • many species of spruce
  • Banks pine
  • Douglas fir
  • Hornbeam
  • Pastures

Interesting: If the ground conditions are bad, shallow roots do not find optimal support, which in turn endangers them in a strong storm. But: if the soil fits and / or if there are suitable rocks nearby, shallow roots often develop good root systems and grow on whole rocks. Then they are stable in most cases.

Walnut tree as a heart root

The walnut tree is also partly considered to be a heart root. This is a kind of intermediate form.

The root of a heart root is characterized by a compact growth and few but strong side roots as well as a hemispherical growth form.

Practical tips

What does the walnut tree root type mean in practice?

The roots of a walnut tree take on similar expansive dimensions as the crown. For this reason, when planting, it is essential to leave sufficient distance to structures (including basements).

Note: Some hobby gardeners have already had the experience that the roots of their walnut have “drilled” their way completely through the outer cellar wall. You should absolutely avoid such masonry bursts. So plan at least twelve to 15 meters away from houses when you plant your walnut.

If your walnut tree is in a strategically unfavorable place, it is imperative that you try to dig up and replant the plant.


It can be logically derived that the walnut tree has developed into a deep root. It originally comes from dry regions. So in order to be able to fill up with enough water, the walnut had to go deep into the ground. Due to this deep rooting, a walnut tree is nowadays able to cope with longer dry periods everywhere.