Severe!!!! pruning very tall Forsythia

20 years ago

When I bought this property in 2000, the fairly long winding driveway had a row of tall Forsythia in partial shade in Tolland County's rocky soil. The plants were tall, some as high as nine feet. Most of them had no branches until about three feet up. Diagnosis: no pruning for many years, plus perhaps seeking the sun.

I pruned out the vine-like branches and took a little off the top. I fertilized twice. Two years later, the plants had a more prolific bloom, but they were just taller. Repeating this from year to year, I have a collection of plants than bloom like yucca or candlesticks: everything is at the top.

I know that even the most severe pruning should leave a strong bud on a branch. However, that would only shorten plants that would still have no blooms until about three feet up.

One poster on the poll on pruning Forsythia says that he tried to kill his plants by severe pruning, which I would take to mean cutting them with no buds remaining. The plants did not die, so he had to pull them up.

If Forsythia is that robust, would I be able to prune the plants back down to bare branches and expect the plant to be able to generate branches and leaves from stored resources? I am considering removing the plants and starting over, so I would be willing to risk killing the plants. A compromise would be to prune every branch down to a strong bud, and trust the weeping habit of the plant to provide flowers nearer the base. I know that I'll have zero blooms next year.

Featured Answer

lindac

20 years ago

Forsythia can take very severe pruning. If I am not mistaken they bloom on year old canes.....that is the canes made this year will produce floweres next year. So your goal is to stimulate more canes.
The "rules" say to cut 1/3 of the stems back to the ground every year....in the spring after blooming.
Given what you are saying about over growth, I would cut 2/3's of the canes down to the ground in the next 2 weeks, and do the other 3rd next year.
If you cut everything down to the ground you will have very small bushes for several years....well maybe only 2 years....and then you will have tos tart with cutting out 1/3rd of the canes again.
Cut 1/2 or more of each bush to the ground.
Linda C

Sort by:Oldest

Comments (6)

morz8 - Washington Coast
20 years ago
Severe pruning isn't going to kill them, and you may still have flowers next year. Flowers form on prior year's growth - if they are done flowering and you prune early, there is still time for resulting new growth to mature in time to flower next year. You can cut back old growth to about four inches from the ground, and in extreme need cases (old neglected shrubs), you can do that to the entire shrub (although leaving 3 canes somewhat longer is considered safest).

Don't hesitate to be aggressive in pruning these fast growing plants - well established and healthy, they will put on as much a 3' per year.
Related Professionals
Baltimore Landscape Architects & Landscape Designers · Ardmore Landscape Architects & Landscape Designers · Manhattan Landscape Architects & Landscape Designers · Lancaster Landscape Architects & Landscape Designers · Coeur d'Alene Landscape Architects & Landscape Designers · Magnolia Landscape Contractors · Carbondale Landscape Contractors · Bowling Green Landscape Contractors · Beckley Landscape Contractors · Anchorage Landscape Contractors · Houma Architects & Building Designers · Laredo Architects & Building Designers · Hartford Architects & Building Designers · Leominster Architects & Building Designers · Bozeman Architects & Building Designers
agardenstateof_mind
20 years ago
I can report excellent results with pruning out one-third of the old canes. Most of my forsythia are in a mixed shrub border and have been blooming nicely, but were just getting too tall. I took it slow, standing back every now and then to see how it was going. In the end, I had an enormous pile of branches I'd pruned out ... but the bushes didn't look scalped or even pruned! ... just more civilized. I guess that's the idea. They bloomed beautifully this spring.

I'm so glad you're looking to do this the right way. There's another forsythia at the base of our driveway, but on the neighbor's property. The former owner used to keep it pruned in the shape of a (very large) egg ... lol ... just not natural for this shrub!
jannie
20 years ago
Ugh, I just can not picture forsythia as topiary subjects!
catmom50
19 years ago
My forsythia is 5 years old, and has never bloomed. It is in a sunny with late day partial shade area. I feed it miracle gro all purpose.
I have pruned it a bit, but not much to prune.
Should I do a down to the nub prune, or what??? Need help.
lorrelle822_btes_tv
15 years ago
I have always loved forsythia and bought 3 plants when we moved into this house 3 years ago. The first year (one year after planting) the plants were scrawny and barely bloomed.
Last summer one plant was accidentally mowed down twice and then my 8-yr old grandson whacked it down with a weed-eater. I was really upset because I thought that was the end of it. Well, this year it is the best of the three plants and taller than I am. So I guess pruning really helps-even if it is done on accident. I like the wild look-let them grow shaggy and which ever way they want to go. So much prettier than those that are pruned into box hedges.