Best moved when fully dormant in the fall.

If you move it now I would prune it back hard (you would lose the flowers this year). It should do fine as long as you baby it a little.

Lilacs often produce offsets-new sprouts from the roots, which are eminently movable, and are genetically identical to the mother plant. Might there be one or more of these present? And if so, wouldn't that possibly make the most sense? To my way of thinking, moving a 7 foot tall lilac bush sounds like work!

+oM

i would find a mail order place.. and spend 20 bucks to have a new one mailed to the new house ... crikey.. you are talking a 3 foot root mass ...

in the alternative.. if its the type that suckers.. just pot up one of the suckers ...

either can be done right now.. in my z5MI ... as they will be dormant for another month or so ... though.. regardless .. you can barely kill the things ...

a latin name would help.. as i dont know what a European L is ...

ken

I have moved them in terrible conditions. They are survivors. Don't move the main plant. Take the off shoots or suckers. I moved some from my childhood home to my current home. (from 6b to 5b). I took some shoots that were 2-3 feet tall.

I have moved them around mid may & more in mid July.... They are tough.

You will not get flowers this year. Patience will be key.

Good luck!