Dying Lilac - Ask Extension
My lilac bush is severely stressed. I have the regular powder mildew appear from time to time. This year was completely different. In the past 2 weeks...
Knowledgebase
Dying Lilac #722414
Asked September 09, 2020, 4:56 PM EDT
My lilac bush is severely stressed. I have the regular powder mildew appear from time to time. This year was completely different. In the past 2 weeks or so, the leaves turned black / dark brown on the edges and fell off. The bush is almost bare. In the past 20 year, I don't recall My 40 + year old bushes ever being this sad. Can you help identify and mitigate the problem? Thank you!
Baltimore County Maryland
Expert Response
You are not alone. We are getting a good deal of sad-looking lilacs questions.
This time of year is not a good time to try and rate how a woody shrub is doing. This late in the season everything is starting to look rough and tired, and stressed plants are dropping dying leaves early.
Was it full of leaves and did it bloom well in spring? If so, don't worry.
At 40 years old, if you haven't done it recently, it's time for a renovation.
Also, in an older landscape, it's time to reassess if it is still in a good position. Lilacs need full sun to bloom well. Otherwise they strain and stress for the light by growing tall and spindly and may not bloom or only too high to appreciate. Upon looking closer at your photos, it appears that you do have buds set for some flowers next year, which is a good sign.
To renovate, the first thing we suggest is to cut out all dead wood, all the way to the ground. This can be done now.
In early spring, cut one third of the oldest branches all the way back to the ground. Each spring for the next two years after that, do the same thing. By then you will have reinvigorated the whole plant.
Another way is to just cut the whole shrub down next spring and let it grow back. That is more drastic and will sacrifice flowers for a few years.
We can't tell for sure, but it appears that maybe English Ivy is climbing this shrub?
Definitely remove that and consider replacing the invasive ivy with another type of groundcover.
Christine
This time of year is not a good time to try and rate how a woody shrub is doing. This late in the season everything is starting to look rough and tired, and stressed plants are dropping dying leaves early.
Was it full of leaves and did it bloom well in spring? If so, don't worry.
At 40 years old, if you haven't done it recently, it's time for a renovation.
Also, in an older landscape, it's time to reassess if it is still in a good position. Lilacs need full sun to bloom well. Otherwise they strain and stress for the light by growing tall and spindly and may not bloom or only too high to appreciate. Upon looking closer at your photos, it appears that you do have buds set for some flowers next year, which is a good sign.
To renovate, the first thing we suggest is to cut out all dead wood, all the way to the ground. This can be done now.
In early spring, cut one third of the oldest branches all the way back to the ground. Each spring for the next two years after that, do the same thing. By then you will have reinvigorated the whole plant.
Another way is to just cut the whole shrub down next spring and let it grow back. That is more drastic and will sacrifice flowers for a few years.
We can't tell for sure, but it appears that maybe English Ivy is climbing this shrub?
Definitely remove that and consider replacing the invasive ivy with another type of groundcover.
Christine
