By David M . Anderson , MCLP , MCA
Rejuvenation pruning is the aggressive cutting of stocks ( of certain shrubs ) to the ground in late winter . There is a limited group of plants that consistently respond well to this type of pruning ( I only have experience with the ones that I have worked on in The Boston area ) Forsythia is one of the best . On March 26 2022 , I did a partial rejuvenation pruning to a large , old and tired forsythia . I cut some large older stocks on the back side of this plant to the ground . Because this is a very visible location , the client was concerned about losing screen and how the plant would look in the short term . So , instead of cutting the entire plant to the ground we did a partial pruning . If you are going to take the partial approach start by cutting down the larger older stocks . By taking this strategic approach you can preserve most of the plant while cutting down portions of the older wood over the course of a few years . In most instances if you do this to the right species in late winter you can cut the entire plant to stubs 3 inches above the ground and it will grow back with a younger healthier appearance . However , you need to set your clients expectations . Even though I have done this for a long time ; every time I cut plants completely to the ground , I offer this disclaimer “ if the operation is a success , you can visit the patient if not you can claim the body ”. That ’ s my corny way of saying if a couple plants die don ’ t be surprised . This very rarely happens but it can happen . There have been a few instances of cutting down entire privet hedge rows when a plant or two was lost . The second thing your client needs to know is . it will take a few years for the plant to grow back to the previous size . So , if that is going to be a problem take the partial approach over a few years . Usually , these types of plants grow back over the course of a few seasons and as the term rejuvenate suggests you replace your old , tired
shrubs with younger vibrant shrubs . And it ’ s a lot less money than replanting .
If you decide to experiment with this type of pruning you need to know three important things ; what shrubs will respond well to this aggressive pruning , the condition of the plant and to do it in March or April . If you do this to the wrong plant , you will either disfigure or kill it . If you do this to a plant that is weak or almost dead … guess what ? If you do this in the fall , summer , or early winter even to the right species you can do more harm than good . The last thing to consider is if you want the best results fertilize the plant in late fall ( October 15 to December 1 ) depending on the weather that year ) before you prune . I prefer a balanced liquid tree fertilizer with 5- 10 % nitrogen . If the soil temperature is above 45 degrees , the plants will still be actively absorbing nutrients . With the fertilizer actively working in the plants before the pruning it adds an additional boost that really make a difference .
Rejuvenation or basal pruning is a great tool to have in the pruning toolbox . Just remember the Decision Pruning Guide matrix before you prune anything . Species ; know your plants and how they will respond ( always the hardest one ), timing ; what time of year ? condition ; if I prune this plant , am I doing more harm than good ? expectations : how long will it take to respond ? Will my client be upset if it looks bad , they lose screen and takes a long time to grow back ? and follow up ;; will there be more work I need to commit to doing in the future because every plant will have a reaction to pruning .
See Before & After photos on page 9 !
MALP Newsline | Winter 2025 5