Obtaining and Planting Your Trees - Growing Organic Orchard Fruits - page 358

Certain bacteria can also be valuable as a root treatment at the time of
planting. Crown gall is a bacterial disease that causes tumor-like galls on
the roots, collars, trunks, and stems of many species of woody plants. The
disease is caused by Rhizobium radiobacter (formerly known as Agrobac-
terium tumefaciens ), which dwells in the soil and can exist without a plant
host for many years. The disease is usually spread to uninfected fields on
infected planting stock or on soil particles carried from an infected field on
equipment, runoff water, or feet. Certain closely related but nonpathogen-
ic bacteria can protect against crown gall by colonizing the roots and ex-
cluding the disease organism. Dipping the bare roots into a slurry containing
Rhizobium ( Agrobacterium ) radiobacter strains K84 or K1026 immediately
before planting can provide good protection for at least the first year and
help the plants become well established. Be sure that the product you use is
registered for certified organic growers and for your state or province.
Adding Amendments to Soil
As we discussed in chapter 4 ➔ , if you are going to add an amendment
such as compost, peat moss, or other organic materials, with the exception
of phosphorus, it is best to add it to the planting row or the entire orchard
rather than to the planting holes.
Adding amendments to planting holes can create very serious problems
and should never be used for fruit trees and bushes. The rule of thumb is that
the only thing besides the roots that goes into the hole is what came out of
it in the first place.
Add amendments throughout the planting row or entire orchard and till
them in 6 to 12 inches deep. For bush fruits, you may obtain satisfactory res-
ults by amending only the planting row. Fruit trees have much larger root
systems that quickly grow far beyond the planting row. Once the amend-
ments have been applied and tilled in, mark the planting rows, dig the holes,
and set the trees. You gain all of the benefits of the amendments and avoid
the problems. The amendments will be available to the growing root systems