Expert: C.L. Fornari - 6/27/2008

Question
We have 3 lilac trees 2 white 1 lilac.  last year one branch on a white died and we pruned it off.  This year both whites look very sick leaves are dying and the flowers were very small and died quickly.  Now one branch on the lilac one has died help

Answer
Rita,
A plant that is dying branch by branch may have a borer, a disease or may be showing symptoms of too wet or too dry soil.  ( IF the plant has automatic irrigation that goes off frequently that could cause the problem.)  

Of the two main disease problems of lilacs - powdery mildew and botrytis blight - the mildew is usually just cosmetic but the botrytis can cause dieback of new shoots. There are also borers that can attack lilacs - look for small holes where an insect may have entered.

There is a great on-line summation of lilac problems here: http://www.ct.gov/CAES/cwp/view.asp?a=2823&q=377792 - perhaps that will help as well.


If this were my plant I'd be sure it got watered deeply once a week, and I'd dump a bag of composted cow manure around the base of every plant, clip off all dead areas  and hope for the best!

I hope this helps,
C.L.