We bought a house back in 2007 and inherited two lilacs. I like them very much! However, the one in back seems to be struggling and I'm just not sure what to do for it.

For starters, it had a huge vine choking it off and we didn't even realize it for the first two years :P "My, the lilac looks so green and bushy!" Nope! When we realized what was up and went to chop off the vine it seemed like we removed half the biomass! Scraggly lilac after that. (I think the vine was some kind of honeysuckle but it's been a few years - not the awesome smelling kind of honeysuckle either, alas)

Since then the lilac just looks kinda scraggly and leggy. I've read up on how to prune and that only 3 year old branches bloom, so my understanding is to chop off 1/3 branches per year until you get a nice bushy lilac again.

The problem is, I really don't see many suckers to nurture? We've pruned it back some last year to make it not block the (new) shed so much but I'm worried that I don't see much growing to replace things! Is there any way I can encourage suckers? Or is there something in the environment the lilac is not happy with?

The lilac in front is doing nicely and sends up tons of suckers each year. The neighbors' lilac, about 4 feet from mine, looks wonderful and busy too XD

Some photos:

Here are the lilacs in bloom from last year. The darker purple one is mine, the lighter is my neighbors'.

Here is the current status:

The base of the lilac: I can only see two decent suckers! (upper right)

Just recently I noticed this:

Eww! Are these guys a problem or just opportunists partying on some dead wood? If they are a problem, what should I do about them?

Any advice you can give would be appreciated!

when its done flowering.. cut the rest to that height ...

and with no insult to the root system.. it will be 3 to 4 feet by fall ... but it MIGHT NOT flower ...

if you want to insure flowers next spring ... then use REJUVENATION PRUNING [which you can google] ... which sped up for lilac.. will insure flowers on the old wood.. while the new wood grows and ages ...

the bugs are irrelevant .. IMHO ... just a warm day after winter.. and a hatch of whatever ...

third pic.. if that is the other lilac on the left ... cut the ones that are weeping.. this spring.. after flower.. they are bending.. because they were cut at height.. and new branches sprouted out where the trunk could not hole them up [if you go study such.. i am positive you will see the prior cut] ... after flower next year... cut the rest of them down per REJUVENATION PRUNING

w/o rejuvenation pruning.. those lilac.. theoretically .. have the potential to fill your entire yard.. over the decades ...

and dont worry about it .. you probably couldnt kill them if you wanted too.. short of putting roundup in the cut stubs ...

good luck

ken

Ken: I admit rejuvination pruning might be a wee bit more extreme than I'd like to go as I love the flowers XD Also if we sell the house this year those stumps would be at their ugliest!
Also, according to this website I looked at "For species that produce few suckers and form water sprouts on the main branches (e.g. S. x prestoniae), any necessary rejuvenation pruning should be done over a period of two to three years." and I suspect this lilac may be one of those kinds?

Rhizo: AAAAAA! TERMITES! AAAAA D:
No I have not seen them fly but I have not been watching closely and those sure do look similar D:
IDK would cutting off the stumps and treating what remains get rid of them? What should I treat stumps with to prevent this kind of thing?? D:

and yes.. it can be 3 years .. or one year.. with lilac ...

good luck

ken