|I have a forsythia that has been in the garden for a few years. question is: when to prune and how much?|
|Your forsythia can be pruned after it has finished flowering. If flowering isn't important to you, you can prune it now. Established forsythia will rebound from a drastic pruning session so you can take one-third of the live plant material off, plus thin out some of the oldest stems. This will result in lots of new growth and an even more spectacular flower display next year.