I have two Lilac bushes i... - Ask Extension
I have two Lilac bushes in my yard, at lese I think they are both Lilac one of them has never bloomed the 2nd does bloom but nothing special. My quest...
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I have two Lilac bushes i... #155169
Asked October 01, 2013, 8:10 AM EDT
I have two Lilac bushes in my yard, at lese I think they are both Lilac one of them has never bloomed the 2nd does bloom but nothing special. My question is, a month or so after the leaves come out they get a white milky film over the leaves. I also have an Azalea bush that also gets that milky film on the leaves which occurs after it blooms. Can you tell me what the film is and how to eliminate the problem? Below are pictures of the leaves, just click on the links to my Dropbox.
https://dl.dropboxusercontent.com/u/77299309/Pictures/2013-09-15%2012.40.51.jpg
https://dl.dropboxusercontent.com/u/77299309/Pictures/2013-09-15%2012.42.39.jpg
The last couple of years we have be inundated with gnats in our yard. We cannot walk through the yard or work in the yard without being swarmed by the gnats. We have our yard sprayed for insects which does nothing for the gnats. If I have to work in the yard I have to spray myself with insect repellent. Any ideas on eliminating the Gnat problem?
Thank you for any information you can give me.
Allegany County Maryland
Expert Response
Your lilacs have powdery mildew, which has become an increasing problem in Maryland in the past few years. This could be because of climate conditions changing (it is warmer in Maryland) and/or because the fungus itself has become more robust. At any rate, you can spray a fungicide labeled for powdery mildew in spring at the first sign of the problem. Horticultural oil will work, too. Some lilacs are bred to be resistant to powdery mildew, and if the problem is severe on yours, you might want to consider replacing them with resistant varieties.
On the other hand, it takes several years for most lilacs to produce flowers, but in the past few years--again because of the warming climate--the lilacs in general have not flowered well. We are in lilacs' southernmost range anyway, because lilacs need a good cold chilling period in the winter in order to produce blooms. When we don't have winters that are cold enough, they cannot flower.
As for the gnats, do not spray your yard. That is a temporary attempt that will kill more of your beneficial insects that eat gnats, than the gnats. Make your yard dryer and less attractive to gnats by pruning shrubs or trees back or more open to improve air circulation. Also, be sure there is no standing water or soil that remains soggy for long periods which needs to be trenched or graded to improve steady soil drainage..
ECN
On the other hand, it takes several years for most lilacs to produce flowers, but in the past few years--again because of the warming climate--the lilacs in general have not flowered well. We are in lilacs' southernmost range anyway, because lilacs need a good cold chilling period in the winter in order to produce blooms. When we don't have winters that are cold enough, they cannot flower.
As for the gnats, do not spray your yard. That is a temporary attempt that will kill more of your beneficial insects that eat gnats, than the gnats. Make your yard dryer and less attractive to gnats by pruning shrubs or trees back or more open to improve air circulation. Also, be sure there is no standing water or soil that remains soggy for long periods which needs to be trenched or graded to improve steady soil drainage..
ECN
