Elderberry bushes are gaining in popularity. This native shrub is easy to grow and is adapted to a wide range of climatic conditions, including wet areas. It features attractive white flowers and nutritious and delicious berries in summer. The shrub is also a favorite of birds and wildlife. However, until now no one knew the best way to prune the shrub for highest fruit production.
Researchers at the University of Missouri trialed four different pruning methods to determine which one favored the best elderberry production. From 2000 to 2006 researchers on two sites in southern Missouri grew 'Adams II', 'Bob Gordon', and 'Netzer' elderberry varieties. Some bushes were pruned all the way back to the ground each year, some pruned back to the ground every other year (biannually), some selectively pruned to remove old wood, and some not pruned at all.
Researchers determined that for large-scale production of elderberries, pruning shrubs back to the ground each year worked the best. Although this technique yielded up to 20 percent less fruit than the other techniques, annual pruning resulted in high average yields, fewer disease problems, less loss to birds because they had difficulty landing on the more pliable young stems, and easier overall cultivation. It also reduced labor costs - an important consideration for large-scale growers. (Selective pruning requires that each shrub be hand pruned rather than whole rows being cut with a mower.) However, because higher overall yields were obtained with selective pruning -- removing old, non-bearing limbs annually and opening up the bush to new growth - this technique may be the best one for home gardeners looking to optimize production from few shrubs.
For more information on this research, go to: NY Berry News
Article published on August 12, 2009.