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Need help diagnosing sick lilac bush

Posted by tyandnickysmum WA (My Page) on
Mon, Aug 14, 06 at 21:03

My lilac has had one or two blooms the last few years. Now it looks really bad. The leaves are droopy and then turning brown. They also have gnawing marks from maybe an insect? There is no white evidence of powdery mildew. Checked base and did not see any rodent damage. Any advice would help and i can also email a picture of my poor bush:)

worried in Auburn

Follow-Up Postings:

RE: Need help diagnosing sick lilac bush

Hmmm...I'm not sure, but a pic certainly won't hurt. You can email it to me ( and I'll post it in this thread.

How long has the plant been in the ground? Do you think it's getting adequate water?


Pics for .....RE: Need help diagnosing sick lilac bush

It sure looks like it wants more water to me, but I imagine you've already given it a big drink to see if it perks up?

Here are the pics Jessica emailed me so others can take a look and offer suggestions too. Keep us posted and good luck!

Pic #1

Pic #2

Pic #3

RE: Need help diagnosing sick lilac bush

  • Posted by bboy z8 WA USA (My Page) on
    Wed, Aug 16, 06 at 23:15

Needs water.

RE: Need help diagnosing sick lilac bush

It does look like it needs water, but it also looks like some insect damage. The leaves look different than what I know a Lilac leaf to look like. The shape is different.

RE: Need help diagnosing sick lilac bush

  • Posted by jean001 z8aPortland, OR (My Page) on
    Thu, Aug 24, 06 at 1:58

The insect damage on the leaves appears to be that of root weevil adults.

If the plant isn't wilted because of dry soil or even excess moisture, perhaps the root weevil larvae have damaged the roots or the crown of the shrub.

RE: Need help diagnosing sick lilac bush

  • Posted by botann z8 SEof Seattle (My Page) on
    Thu, Aug 24, 06 at 10:56

Judging by the brown grass in the background and the hanging leaves, I'd say it needs water. The sooner the better. Lilacs appreciate a little lime in our acid soil too.

RE: Need help diagnosing sick lilac bush

Seems like everyone has given up on this, but in my opinion, the roots have been smothered. Since all of the leaves are drooping but don't seem to be damaged, it isn't a pest. 80% of the time shrubs are planted too deep and while it may take two or three years to debilitate the plant, it's inevitable doom. Oxygen can't get to the roots and the plant slowly suffocates. Fortunately, Lilacs are deciduous so during their dormant period you can replant them higher -- about two inches higher than level grade. It won't hurt to cut the branches back about 1/3 at the same time. Once replanted, water deeply twice a week.

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