How to prune a lilac?

[MaryMary]

We have a lilac outside the living room window. It has grown huge, and while I love the smell of lilacs, it just really needs pruned. It is within a week of blooming, and I'm going to prune it soon after. It doesn't have that many blooms on it, either.

It is over 8 feet tall, and I would like to bring it down to a little under 5 feet. (It would be nice to see out the window!) Can I bring it down that much in one cutting without killing it?

Any advice for how to get the most blooms next year?

 

[Plantdoctor]

Virtually impossible to kill a lilac, the chances are that by cutting back by half means you may lose flowering for next year,so enjoy the flowers this year,then the improved light,then it will bounce back.

 

[Larisa]

If briefly and clearly, then so.
I have a young lilac and cut off a little after flowering.

 

[Everbrown]

General rule I think is to prune old think stuff (inch or two in diameter) sick stuff, then on top never more them 1/3 the height. And for Lilac right after bloom is done as they start new growth then

 

[Mark56]

Yep, cut straight after flowering as they bloom on old wood. Mine are super early this year, so I will be cutting them back as soon as the flowers fade.

 

[MaryMary]

Ok, thank you!!

@Mark56, mine are blooming about a month early, too!

 

[Esther Knapicius]

Not now to prune, the flower buds are almost ready to open. Prune in, maybe July.

For any shrub, I like to prune away any limbs that are rubbing on another limb, choosing which one is visually nicer. then follow the above suggestions.

Have three types of Lilacs on my property. Several is the mini kind, I think there are 6 of those. They stay about 6 foot tall. the other is a regular type, about 2 or 3 of them. Then one tree, that blooms much later, trying to get a climbing rose to cling to it.

 

[MaryMary]

Not now to prune, the flower buds are almost ready to open. Prune in, maybe July.

That long after they bloom? I thought it was supposed to be right after blooming? I was planning on 2-4 weeks from now...

 

[Greenhorn]

Our Lilac around here is Ceanothus spp. yours must be Syringa spp.

 

[marlingardener]

When we bought a house in upstate NY, there were lilacs in the back garden that were 8 to 10' tall, bare up to about 6'. After their sparse bloom, I cut them back by half, removing dead branches and "rubbers" like Esther recommended.
I did this in a one year period, because I just couldn't stand the way the lilacs looked. They bounced back, fat and happy and full of blooms the next spring.
Whack away, MaryMary!

 

[MaryMary]

When we first moved here, 8 years ago, I did not know when to prune a lilac, so we did it in the fall. The next year, there were no blooms, so online I went, to find out why.

For some reason, it has never really bounced back. I've never seen it covered in blooms, and we haven't pruned it for two years now. Since it fills the window, and I do like to see out the window, I'm going to prune it this year.



Another question about lilacs. If I wanted to dig out a sucker and put it in a pot, could I leave it outside over the winter? Would the roots freeze? Would I need to bring it in for the winter? Does it need a dormant period? I'm thinking of something like an indoor tree, not necessarily a bonsai. (But isn't it beautiful? )

 

[Plantdoctor]

Some trees need to be outside, l would put lilac in that category, never heard of it as a houseplant, bonsai is a bit more specialised and needs a degree of expertise to do it right.

 

[MaryMary]

Some trees need to be outside, l would put lilac in that category, never heard of it as a houseplant, bonsai is a bit more specialised and needs a degree of expertise to do it right.

So I would have to leave it outside over the winter, and hope the roots don't freeze?

I just want to be able to bring that smell inside, without having to cut off blooms. I would gladly move the pot in the house one week a year, then put it back out!!

 

[Plantdoctor]

Any tree,confined to a pot, even if hardy is liable to damage if the roots freeze.

Just don't think a lilac is a suitable houseplant,but go on and buck the trend .

 

[Esther Knapicius]

That long after they bloom? I thought it was supposed to be right after blooming? I was planning on 2-4 weeks from now...

As your from Southeast Ohio, similar temp as me. My lilacs are not even blooming yet, so anticipated that July would be a good time, when all is done blooming.

As far as the bonsai Lilac tree, I would do a little research to find out which one to use for them, as there are several varieties of lilacs