[momtothree]

What is sort of amusing to me if that Lilacs are suppose to be “easy” (compared to Tea Roses and such). Almost everyone you know had a Grammy that had a spectacular one in their yard.. filling the air with the most heavenly scent. I did read they like acidic soil (thus the one online recommendation of Epsom Salts). I now remember one woman I knew use to “mulch” hers in pine needles (thus the acid). Thanks, WWH!

[WestwardHo]

Epsom salt,magnesium sulfate, will not increase the acidity of your soil.
Decaying leaves are a better mulch for your lilacs as pine needles contain turpentine, which over time is like added paint thinner to your soil. If it doesn't affect the lilacs, it can kill other things. Pine needles are heavily used in the South for keeping weeds and such down around trees and yard edges. It's heartbreaking to have spring arrive, and no flowers on the lilacs. Even one of those cheap soil testing gagets with the two electrodes that go in the soil will give you a good idea of what your soil needs.