Planting Container Trees and Shrubs

Our understanding of trees is in constant flux. The greatest indicator of this failure to understand is the short life expectancy of trees that are products of our modern growing and planting practices. Today, the average tree in cultivation lives about 7-9 years.

Trimming branches: It used to be common practice when planting a tree to trim the tips of all branches. Science found that the stimulus to grow new roots is connected to the extending tips of the branches. So today the recommendation is to trim ONLY broken and damaged branches.

Treating cuts: It used to be common practice when pruning trees to paint fresh cuts with paint or tar. Today, placing of anything on the cut is believed to inhibit, if not impede a tree’s ability to naturally encapsulate the wound.

Preventing Root problems: Root problems are the major cause of early death. And regardless of the age of the dying tree, root issues appear to be the most frequent cause. The problems we see in the urban forest do not exist as problems in a natural forest. So we can probably assume that most of them are human made. With the arrival of mechanical technology, the tree industry exploded. A mechanical tree planter pulled by a tractor replaced the humans in the field. Today one worker sits on back of the tree-planting machine and a stack of trees. A tree is swept into the ground by a mechanical arm leaving the tree in the ground to be tucked in by dirt moved by the tires of the rig. Years of this practice have created problems that have come to the attention of professional arborist and scientist.

A few autopsies revealed that the planting method promotes two deadly outcomes.

• First, the machine plants the tree as much as 8” too deep. Planting depth is crucial to the health of a tree. A properly planted tree has “hips” or more professionally speaking – a “root flair.” These hips are prevalent in the natural forest but rare in the urban landscape. When the flair is buried a tree may live for a few years but will never become the tree it might have been.

• Secondly, all the roots tend to grow in the same direction and wrap around each other forming the letter J. These are called Jay Root problems. The trees have very little stability and are likely to come down in a storm just about the time it is big enough to give shade.

Research is suggesting that we should reduce any and every tree – container or ball & burlap – to bare root for planting. (Warning: creating a bare root tree, called root washing, requires specific steps and safety practices. Do not try this without research or instruction.)

To promote rapid growth in the potted plants, container plants nurseries use excess nutrients while decreasing other complications by adding fungicides and insecticides. Unless these plants and their roots are washed free of these additives, they seldom establish healthy relationships with their new environment. So again, root washing is being suggested. Don’t forget to research it or get good instructions before you try

KB, Garden Steward