Forsythia Bush Pruning. With diligent trimming forsythia can be kept from the overgrown sprawl that is a common complaint. A full grown forsythia shrub forsythia spp can spread over 12 feet wide and grow up to 10 feet tall.
Things to consider when forsythia pruning. It provides you with an opportunity to continue your plant s growth in the desired shape once new growth comes in. Prune the whole stem if your forsythia bush is totally out of shape and if think that pruning wouldn t work for you to enhance its appearance trim it off from the bottom.
If you wait until summer or fall to trim forsythia bushes you ll find that the number of flowers that you get the next spring will be much less than.
Only when they mature should you prune them once a year. Since these durable shrubs need little care in the way of soil and nutrients forsythia pruning is a chore that can easily be done annually. They can grow 8 feet stems in a single season. Young plants may only need a modest trimming.