Goji Prunning tips
Goji grows very fast in the summer when light, temperature and water meet its needs for growth and development. Without any pruning a goji tree would become ugly looking with unreasonable canopy structure and shape, consequently inhibit its yielding ability.
In Ningxia China (home place for goji), goji tree was traditionally pruned to umbrella shape. In recent years two new canopy models were adopted to enhance goji's yield potential. The two models are '3-level' model and 'cylindrical' model.
Goji pruning is one of the key learning’s for successful goji cultivation. Below are some tips:
1. First-year goji plant pruning
a. Leave the largest healthy shoot as main trunk; remove any lateral shoots below 50 cm
b. When its growth reaches 60 cm, remove the growing tip of the main stem to stimulate growth of side branches.
c. For any new side branches that bear <45 degrees angle from main stem, remove them. Leave 3-4 lateral shoots with >45 degrees angle from main stem
d. After all remaining lateral shoots grow to 30 cm length, if there is any upward growth from the top of the main stem where the old growing tip was removed, leave the largest one as main stem for the second year.
2. 2-5 years old goji tree pruning
Traditionally goji trees were pruned during winter in dormancy. To achieve better yield and higher quality, however, summer pruning is necessary. In goji pruning two types of shoots need to be removed during summer to control overgrowth of canopy and achieve reasonable structure: suckers and root sprouts.
Suckers: New shoots put out from trunk or large branches, especially from the spot where old branches were previously removed. Suckers are usually shoots with upward fast growth. Suckers do not bear flowers thus consume much of nutrition which can be otherwise utilized by flowering branches. Suckers need to be removed completely from the base. For a healthy adult goji tree a lot of suckers grow out every season, it is a good idea to remove the shoots as soon as they are identified.
Root sprouts: Root sprouts grow from under-ground roots, especially form the spot where a root was previously cut off or damaged during cultivation. If no measure is taken these root sprouts would turn to new trees and eventually make field management very difficult.
For any other branches, follow the instruction above to prune (remove shoots according to their angles from main stem). Sometimes it is necessary to remove or cut short some fruiting branches to leave some space for light penetration and air circulation.
Here is illustration of the three canopy models for pruning a goji tree.