Monster lilac - retaining wall problem

14 years ago

Hi, I wasn't sure at all where to put this post, so I hope it's ok here!

I'm not really sure what to do about this (though I have my ideas, of course), I would like to hear back from some one who may know better before I do anything at all.

I have a lilac in my front yard, and right now it's itty bitty. A year ago, however, I'm told it was massive. At least 10 foot tall and "took up the whole front yard" on the side that it's planted. The front yard sits six feet up from the street, in 3 sections, in a very old retaining wall that I can't afford to replace.

Last year, while renovating the house and leveling the yard, the workers chopped this lilac down to the stump, thinking that would kill it. As you can see, it's alive and kicking, and if you would believe it, ticked off!

Here's a pic of the lilac.

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This past year, it's been putting up shoots all over the place. I'm finding them up to ten feet away, I mow them down and that's that.

But my problem is this retaining wall, on the corner.

The bush is planted 4' from the side, and 5' from the front. I know this wall is old, and you can see in the firt pic that it's been patched along the top with cement. The corner looks precarious, and certainly needs repaired ASAP.

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Back to the bush. I believe it's possible that the roots from the lilac are exerting pressure on the wall and that the bush needs to come out. I'm not fussed, because I don't want to let it get "Huge" again, and I understand that keeping it trimmed will nix any future blooms anyway.

I worry that cutting it down will compel it start putting out shoots again, exerting even more pressure on the wall?

If I do take it out, what is the best way to do it, with out damaging the wall any further? Any thoughts or suggestions please?

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Comments (4)

duluthinbloomz4
14 years ago
I don't know if it's the lilac impacting your retaining wall - looks like failure due to the ground heaving, shifting, and settling. Not a mason, but would think freezing and thawing (or a bad mortar mix) could cause mortar to pop. And now that it's underway, it'll continue with or without the lilac.

The root system is probably fairly extensive if you're getting suckers ten feet away. If you want to get rid of it, dig around it in a circle, chopping off the roots as you go. Labor intensive, but doable. Then paint the fresh root cuts with a non-selective herbicide like RoundUp or some other stump killer type product.

Or, have it it professionally taken out and the stump ground. You might still get a sucker or two, but since they'd no longer be attached to the parent, mowing over or ripping them out should take care of them.

I have many, many, many feet of old and huge common lilacs -and I've never seen a sucker more than 6" from the parent plant. But I concede different varieties do different things. And I kind of welcome the close in suckering since it replenishes any old wood I might lose.

There are wall and tree/shrub experts on the forum; hopefully they'll chime in.
laag
14 years ago
I agree with Duluth. The lilac is not the most significant problem with the wall.

I think you'll be very impressed with the blooms next year. You can control the size of the lilac by thinning the longest branches down low from time to time.
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oilpainter
14 years ago
If you want to remove the lilac the easiest way is to cut it down to ground level. Then put some deep saw or ax cuts across the stump. Fill these cuts with granular fertilizer. The same way fertilizer will burn roots before it's disolved will kill the stump.

When a tree or shrub is cut down it will send up suckers from the roots. That is why you are finding them all over, so you know how far the roots go. If there is a sucker there it either came from the roots or from a seed.

While many people like lilacs I personally don't. I don't like the way it grows or the strong smell which I am allergic to
destany
Original Author
14 years ago
Thanks for your input! It's really helpful that you don't think the lilac is contributing to the crack wall. My husband wants to keep it, and if it's not doing any harm, I don't see the point in getting rid of it - if I can in fact keep it in check, that is.

I should have mentioned that the wall is over 100 years old. Not really surprising that it would have cracks and need repairs at this point, there are several other places that have already been patched.

I will tend to the wall and leave the bush alone. :D Thanks!

Monster lilac - retaining wall problem

Comments (4)

duluthinbloomz4

laag

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Monster lilac - retaining wall problem

Comments (4)

duluthinbloomz4

laag

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destanyOriginal Author

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destany
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