Some tips for planting fruit trees
A few basic steps at planting time can impact longevity and performance of an orchard.
It pays to remind ourselves of a few very basic, but extremely important, points when it comes to planting trees.
One is planting depth. With cherries, we know we need to put them in the ground deeper. If the graft union stands 3 to 4 inches above the soil line, we might encounter some problems. On the other hand, when it comes to apples, it is preferred to have shank exposed for 3 to 4 inches after the soil has settled. Keep in mind that the rootstocks dwarfing effect is accentuated by the length of the shank exposed. In some articles you may find recommendations to plant apples on clonal rootstocks so that the union is 6 inches, or greater, above the soil line. In our area of west central Michigan that would not be acceptable because of the dogwood borer infestation and very sandy soils that impose limitations on vigor and thus might compromise reaching the desired tree size.
The second point I would like to emphasis is crown gall control. This is the most opportune time to minimize the problem with crown gall for the life of the orchard. This bacterial disease causes distortion, tumor-like growth on the roots and crowns of many plants. Stone fruits are particularly susceptible. The first step in controlling the problem is to carefully inspect trees upon arrival. All trees showing symptoms of infection should be destined to end up on a “burn-pile.”
Now, the question is how do we prevent inoculation with the pathogen? A very good start would be to use biological control agent like Agrobacterium radiobacter strain 84, i.e. another bacteria that would occupy the same sites and compete for the same food as pathogenic Agrobacterium tumefaciens. Agrobacterium radiobacter k84 releases protein that inhibits growth of A. tumefaciens. Before planting, roots should be either dipped in or sprayed by water solution containing Agrobacterium radiobacter k84. Spraying is much more economical. One of the trade names that comes to mind is Galltrol. Since this is a living organism it must be refrigerated until the time it will be used. Treatment is not a cure, but prevention!