"Martin Brown" wrote in message
...
Can anyone recommend the best time and method to trim a neglected (~5
years worth) Lilac tree to restore the thing back to it's main
cultivated graft?

The tree is presently about 2/3 sucker growth to 1/3 true flowering form
easy to tell at this time of year. I hope to mark the good and the bad,
but wonder if it can take such drastic pruning in a single shot.

I managed to kill one in an even worse state in a previous garden by a
combination of aggressive rejuvenation and a hard winter. I'd prefer not
to repeat the same mistake again.

Any tips for best time to do it and how much to take off per year?

Thanks,
--
Martin Brown

Hi Martin,

You should prune a lilac (syringa) mid to late summer, after the flowers
have faded. Renovate in the winter. To renovate you take the whole plant
down to a couple of feet, however you are unlikely to see any flowers for
2 -3 years, you could also have a the same problem, as before, where the
whole plant gives up and dies. I'd therefore recommended that you stagger
the hard pruning over two or three years, taking a third of the plant down
each winter. Thinning any regrowth as it appears.

HTH

Cheers

Nick
http://www.ukgardening.co.uk