Thicket of lilac sprouts

I hope someone can tell me the best way to deal with a thicket of lilac sprouts under a 15 year old lilac. Two years ago, I renovated the bed as the lilacs were encroaching on the path. The original lilac had grown into a thicket over the years. I dug out a lot of them, about a 10 x 4 foot patch. Last year a forest of little sprouts appeared (about 12 to 18 inches high) so it seems I have just encouraged them.

What to do? Cut them of at ground level yearly and just ignore the roots and hope for the best? Interestingly, the back of the bed faces south yet they are suckering toward the path on the north side of the bed. The ground does drop off on the south side and there is the neighbour's fence as well, though it is not high due to the slope.

Thank you.

 

that's just the way lilac spreads out. not much you can do but continue to cut back the suckers as they pop out of the surface...might also want to put a barrier down in the soil to keep the roots confined.

 

I had the same problem when I removed the Lilac shrubs and roto tilled the remains. Hundreds of sprouts occured. My final solution was to pull each one out. Likely when you cut them, it encourages new vigor, much like water sprouts on fruit trees. Pull them and ruin root grorth.

 

Thank you both for the quick reply. I was hoping there would be a magic answer. Isn't it odd we wait years for a purchased lilac to grow and bloom and sometimes they fail to thrive and here I've got more sprouts than I know what to do with. Hard work digging them out as well but...where is that shovel? I always admire the lilac trees (not bushes) in Colville, Wa. with their single trunks. I suppose they are grafted on privet stock?

These are at the end of my front terrace and I was hoping for a more controlled look.

 

Lilacs renew themselves from near the base, cutting off all basal sprouts may in time interfere with this cycle. An exception is where a specimen has been grafted onto another lilac, in which case all sprouts coming from the rootstock need to be kept cut out. If a planting shows a different flower color on the root sprouts, that is a sign that grafting was involved.

 

No grafting involved with this clump. I started it years ago from similar sprouts from a friend. I do have a Belle de Nancy that I thought was grafted that is sending out suckers (4 so far) about 12 to 18 inches from its trunk. One of them has bloomed looking very like BdeN, certainly not privet. It's heading for the driveway... I have dug down by one of them and severed the link with the main plant, the size of a broomhandle, with my loppers and replanted it elsewhere. Hoping to avoid a forest of suckers.

 

I've never seen lilac grafted on Ligustrum here, but rather other Syringa vulgaris.

 

I must have read about grafting on privet in an English or a French gardening book. I guess the L. vulgaris is for hardiness not to prevent suckering then. What are those Colville lilacs growing on, I wonder. Is it out of the question to knock on someone's door and ask...

 

Have a Syringa microphylla 'Superba' grafted on privet, but don't know which nursery propagated it.

 

That rings a bell, I think I have also seen Ligustrum sprouts beneath lilacs other than Syringa vulgaris once or twice.