Are your old hedges looking tired and are not providing privacy? Your hedge may be a candidate for rejuvenation.
Rejuvenation pruning is an aggressive pruning practice to restore and reinvigorate hedging plant material. Healthy plants and correct timing are important considerations. The preferred time for rejuvenation/renovative pruning is just before bud break in the early spring. The aggressively pruned shrubs will flush and in a very short space of time take on a healthy vigorous growth habit.
I think we’ve forgotten this technique because the customers’ expectations have changed. Many homeowners who don’t know the ins-and-outs of horticulture think that landscape maintenance means keeping the shrubs the same size forever. But hedge trimming like that leads to problems – like an increasing number of dead and diseased/unproductive wood and branches.
One of the best techniques for Ligustrum rejuvenation is to remove growth gradually, also known as selective pruning. The first year, remove one third of the oldest, unproductive branches. The next year, take one half of the old, lingering stems. Finally, in the third year, prune out the remainder of the old branches. New, productive stems should quickly replace the old wood. This method takes longer to complete, but the shrub stays more attractive throughout the rejuvenation.
Another technique used to rejuvenate hedges is to cut to the ground or stubbed back to a severe degree. This looks pretty shocking, but in a few months the hedge will have flushed out full and green and with flowers, for example hibiscus and ixora. This type of “hard pruning” should be done judiciously.
If the rejuvenation approach is used more often, then it needs to be specified in the maintenance contract instead of “pruning”, landscape maintenance contracts should spell out the pruning techniques that will be used for the various hedges on that particular property.