Sonsbeekpark, Arnhem

“We are satisfied with the result achieved in a season and half and the treatment should be sufficient until 2027

Municipality Arnhem

Sonsbeekpark in Arnhem is a special park due to its overall size and height differences. After all, It hasn’t been voted the most beautiful park in the Netherlands in 2012 for nothing.  But even in such a beautiful location, trees need extra care. Research showed that the habitat surrounding a valuable group of trees had become compacted and had atrophied over time due to foot traffic and leaf-clearing maintenance. This group of approximately 30 trees was located in a visible location in the park, in front of villa Sonsbeek.


In the spring of 2020, we carried out a growth­-site improvement for these trees with the TFI method®, including a lime calcium treatment. At the beginning of November, we additionally applied a layer of litter to the trunks, and a leaf compost under the remaining crown areas. This should, within a few years, lead to improved soil structure and better root growth, thereby significantly extending the lifespan of the trees.

Experience and current results as of 2022:

“Work planning in a national monumental park, which receives many visitors each day, is not simple. Due also to the regularity of festivities in the park, it’s not easy to carry out the work in a safe and efficient manner. Certainly not with hundreds of children and parents in the immediate vicinity. The subcontractor for TFI, who applied the litter layer, quickly discovered this fact of life.

Partly due to TFI’s quick response and commitment, the application and the general park festivities were able to take place simultaneously.

In 2021 there was already a clear improvement in the leaf mass of the existing trees. In previous years, a lot of leaves were already falling out from the tree crowns as early as July. Also in 2021 we noticed more and bigger leaves in the trees. Also that year  we again chose to supplement the litter layer. We are very satisfied with the result achieved within one and a half seasons. The treatment should last until 2027, at which time we will review the situation/assess whether additional measures are necessary.”

Codi Duyster
Tree manager and consultant @ Municipality of Arnhem