How do I prune my forsythia? Is it true that it won't flower for a year if I prune it?

Question

Our forsythia has been flowering profusely, but has become too large and is now blocking the garden path completely.

Answer 1

Now is the completely wrong time of the year to prune your Forsythia. Prune it after it has finished blooming. The flower buds are set in the autumn, so pruning too late in the season can ruin your flowering too. If you prune at the 'wrong' time you might loose some flowers (maybe all, depending on how you prune), the plant should recover, and resume it's blooming schedule (provided you don't prune the same way the next season too).


The best method is to prune out the largest branches from the base. The younger branches are the best producers for flowering. Remove 20-30% of the large branches every 2-3 years. Once the large branches are removed, tip prune as desired. Be aggressive, the shrub can easily grow 12" or more in a season. Fertilize lightly once or twice a year... it doesn't require all that much fertilizer to grow up "big and strong".

I hope that this helps

Answer 2

Mr. Potatohead is correct. After the bloom is over is the time to prune. The "preferred" method is to prune from the base, just thinning the plant a branch at a time, rather than clipping it. It does work to trim it into a hedge or bush if you so desire though. I see both around here and they both flower equally well.

Answer 3

Prune a Forsythia only after the blooms/flowers begin to fade. If you trim back lightly after that, you should have your flowers come back next year.

Answer 4

Prune after flowers are bloomed ouit, use hedge trimmer. No it will not die, several years ago when ours got too, too big, my husband used chain saw and cut it way down. By next spring, it came back low of course, but fuller and loaded with flowers. We now keep it about 3 ft high as hedge between neighbor