According to the University of Florida Cooperative Extension, adding fill dirt around your tree incorrectly can easily kill your tree, a slow process that may take up to 7 years before your tree actually dies.

Can you build up soil around a tree?

Avoid tree instability issues when having landscaping done or building a new house. All too often people bring in topsoil or fill and bury the trunk flare of existing trees which will result in a stem-girdling root which destabilizes the tree.

How much fill dirt can you put around a tree?

While trees vary in their tolerance of fill, the amount considered safe to apply is two inches annually. Use a light sandy soil like river sand or pumped sand for filling. Dan Gill is a horticulturist with the LSU AgCenter.