Do not trim your lilacs!!! They hate that!!! It cuts off new growth, and they will not bloom for a long time!
Old time gardeners fed their lilacs vinegar water because they like acid soil.
I’d consider using an iron/sulpher solution.
I think keeping the yard too tidy can be a problem. I think they like dead leaves left over the roots.
I learned the hard way about trimming.
Just my thoughts.
I think you are right. Everywhere I trim mine, to keep it back from the lawn, stops blooming completely. Now, only the very top that never gets trimmed is the only place I get flowers on my Persian Lilac. It appears that blooms only come from new growth on old wood. I am wondering if a severe trim and then just leaving it to grow untrimmed for several years would rejuvenate it. Over the years mine has outgrown it's allotted space. I had no idea that they grew so large.
Hi there, just read your post about not pruning your lilacs....could this be the problem with my Wisteria? I prune it back hard each year following local gardeners but this ‘teenager’ just will not bloom. It bloomed the first year then I had to move the plant to a new location, more sun but same area...do you suppose that stopped the blooming? Have ‘whacked’ the trunk with an ax but that popular notion did not work either. Any and all advice will be appreciated.