Why Won't My Forsythia Bloom?!

[Chattyaholic]

I have two forsythia bushes in the yard, one is in full sun and the other is a bit shaded by a pine tree but neither one will bloom. Oh, there are a few blooms on the bottom of the one in the full sun but very few and none on the other.

I see huge forsythia bushes nearby abandoned houses and barns and they are FULL of blooms, nobody prunes or fertilizes those but they are beautiful.

WHY won't mine bloom?

 

[dandave]

Hi! I found this, and maybe it will help you. I know that I caused a wisteria vine not to bloom by giving it too much fertilizer.

http://www.clemson.edu/psamedia/1999rel.dir/Bbapril1.txt

Coaxing Blooms from Forsythia Bushes

Q: We have a short hedge of blooming forsythia bushes.
About twenty feet away we have another large bed of forsythias
that have never bloomed. Over the past 10 years we thinned it
out, cut it back, left it alone, lightly fertilized it -- but
still no flowers. Is it a lost cause?
A: Before you call it quits, try to figure out the exact
cause of your forsythia's failure to bloom. If the border is
located in a spot that's too shady, the forsythia won't initiate
flower buds. Selectively thinning out the canopy of the
surrounding trees to admit more sunlight should help.
Have the flower buds been pruned away? Forsythia, like other
spring-flowering shrubs, produce their flower buds during the
summer months. Prune your forsythia by removing one-third of the
oldest growth after flowering and thinning out some of the new
shoots at the base.
Have your county's Clemson Extension Office test your bed
for soil pH and fertility. A nutrient imbalance or deficiency may
affect flowering. An excessive amount of nitrogen will stimulate
vegetative growth at the expense of flower bud development.

 

[Chattyaholic]

Thanks dandave, but we've never fertilized it at all.

That's what I don't understand, when I see a beautiful, huge blooming forsythia near an abandoned house or barn it boggles my mind, because I know that nobody prunes/fertilizes those and they're huge and gorgeous!! I just don't get it.

 

[gina2000]

I believe forsythia set blooms early. If you trim them at all instead of letting them go wild, you lose their bloom and instead get a stack of twigs with a few flowers.

 

[phillybeth]

Yup, forsythias set their blooms in the early summer, so if you prune in the summer or fall, you are removing the next year's flowers! If you have to prune, do it immediately after the blossoms drop.

 

[Mamu]

Very few flowers develop on old growth stems. You need new growth stems, not at top but from the bottom.

By pruning your forysthia to keep it in shape you are cutting off next years flowers.

How to avoid an almost flowerless plant. Get your pruners out now, and prune from the base of the plant. If their are 10 main stems cut 4 at the base. New shoots will form from the base, you can still prune from the top and sides to keep the forsythia in the shape you want.

This is what they mean when they say prune 1/3 of the plant. This should be done at least every other year.

 

[Margie J]

This advice and suggestions are very helpful to me. I have dramatic proof in my yard of what late pruning does. The bushes I did trim last summer have a small fringe of flowers while the ones I didn't trim at all are in full bloom.

I'm ready to trim the bushes correctly this year.