By Anniken
Surrey,
United Kingdom 
I have two beautiful white lilacs in my garden. They are about 3m tall and were already well established when we bought the house so not sure how old they are. They have been producing lots of lovely white flowers each year, but last year towards late summer, the leaves on one got brown speckles and eventually went completely brown one branch at a time, almost black and crispy. Took a sample to the garden center to be told it was lacking nutrients because too dry. So we fed and watered. This year it has a few buds on some branches, but many have none and what it does have is way behind the other tree and don't look like opening. Any ideas what could have caused the sudden drying out of one of the trees? (If that is what it is) I noticed a few leaves starting to go on the other lilac right at the end of last summer, but that one looks OK this year. I am quite new to gardening, but would hate to lose one of these lovely trees. I really want to revive it and make sure I don't lose the other one. Please help.
26 Apr, 2010
Answers
Thank you so much for your help. I will have a look for signs and make sure we prune out and look after it well this year.
26 Apr, 2010
Previous question
It sounds as though something is restricting the sap flow to these branches. I have found this article:
http://www.omafra.gov.on.ca/english/crops/facts/borers.htm
go to part 'c' for the bit on lilacs.
Other than this you could try feeding and watering the plant regularly to build up its strength. And prune out any damaged branches asap. Burn or bin them, don't leave them lying around in the garden or the grubs will re-emerge and carry on the infestation. It may take a couple of years of vigilance to get rid of the problem, but if you like the plants then it will be worth it.
26 Apr, 2010