How to Trim a Hydrangea in March
- 1). Avoid severe trimming or pruning of all hydrangeas unless your plant is very old or has grown excessively large. If you neglected to trim old flowers at the end of the previous year's blooming cycle, you can trim them in March for any type of hydrangea.
- 2). Cut all dead stems back to the ground in March for mopheads and lacecaps. Do not prune Annabelle hydrangeas in March or at any other time during spring, according to the website HydrangeasHydrangeas.
- 3). Trim the paniculata types of hydrangeas in March or during fall or winter. These include the limelight and peegee types of hydrangeas. Trim them every other year, concentrating on cutting off branches that cross over each other or that distract from the overall shape of the plant.
- 4). Trim only the paniculata types of hydrangeas into a tree form in March, during fall or winter. Remove lower branches back to the main trunk and leave the major upper branches. Each March after your first pruning, you can trim off any lateral branches that form low on the plant to maintain its tree form.
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