Is it too late to move lilac. They are about 3ft tall and tiny buds have started to grow on them. was hoping to move them this weekend.
I think you may lose the flowers if you move them, or at least put them back as the plant will be trying to establish itself rather than produce flowers. I don't think you will kill it as long as your make sure the new site is as suitable or even better than the old one. Lilac's like the sunshine and prefer humus rich well drained soil that is neutral to alkaline. Make sure you take up a good amount of soil with the rootball.
When you do move it (and I too would leave it until autumn) take as large a rootball as possible - most lilac is grafted and is prone to suckering.