Jan 08, Like many perennials, spring is the best time for pruning forsythia. Do this later in the spring after the blooms fade and the leaves are starting to grow. 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 desired. So, the best time for trimming forsythia is in the spring after the blooms fade.
How to Trim Forsythias Certainly a few items are before beginning pruning to treemulch.buzzted Reading Time: 4 mins. Dec 31, Keep the healthiest looking ones. They will bloom their second year.
If you are wondering when to hard prune forsythias, the best answer is when the shrub gets really rangy-looking, is overgrowing its space or has dramatically reduced flowering due to old age. Hard pruning forsythias is best done in late fall. Jun 01, Any time your tools are sharp is a good time to prune, say some. I think right after blooming is the best time; as you can tell which canes or branches are successfully blooming and which have stopped.
If you prune before blooming, you risk snipping off all those little yellow flowers you were hoping for.