Oh dear - Sorry to hear you've inadvertently offended a neighbor. In anycase to answer your question.

You haven't mentioned the condition of the plant and so I'm not sure how good it's chances for survival are. I surmise it must have been an old established tree and for trees to be transplanted with the least transplant shock, you need to get a good sized root ball, disturbing the roots as least as possible. I think you may have simply done a dig, grab and pull method - the surest way to do lots of damage. In which case, chances are not good.

You could still try to keep the tree alive though. Because it's Fall and plants are going dormant, the tree must have been redirecting it's nourishments to the roots. In other words the roots are better able to survive a transplant in fall rather than in summer. Immediately prepare a hole with good triple mix in it. Plant the tree and reduce it's size by cutting off much of it's branches and trunks - this helps to reduce the amount of nutrients the roots have to nourish in spring. Water once and top mulch. Don't do anything else until next spring. If it survives winter, good. Don't expect any blooms, just be happy if it's starts to leaf out. Don't add fertilizers yet (in fact wait till the following season) You want the plant to grow new roots rather than more branches. Once the plant is going that year. just add leaf mould or compost.

If at all the plant doesn't survive - then offer to buy a new lilac for your neighbors. These shouldn't be too expensive (Loblaws sold some from $19.99 - $29.99) and they grow fast too.

Good Luck.
Ianna

Hi Ianna - Thank you so much for the advice. I can always count on this website for help although usually I"m plugged into the canning site. I have replanted it in a different site that pleased my neighbor and I guess I'll just have to wait. We have very mild winters here (Canada) so hopefully that might help? I will put mulch around it as you suggested and trim it.
thanks again
seaglassgirl

You have to make sure there's no airpockets in that soil. (when you water the airbubbles will come out) Usually that kills. Mild winters are good but you have to observe if there are extreme changes from freezing and thawing. This is what kills most plants which is why you have to mulch. If there's heavy snow, it actually helps because snow insulates the ground. I would even pile up snow in areas I wish to protect.

In anycase, good luck once again.

Ianna

Lilacs are very hard to kill. I've moved them bare root in the summer and they've always survived. They're quite hardy.