Lilac bush not blooming - Ask Extension
Hello!
I planted a lilac bush 4 years ago that has never bloomed. It is growing! But not blooming. There is one more spot in the yard we can move it...
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Lilac bush not blooming #827875
Asked May 01, 2023, 7:55 AM EDT
Hello!
I planted a lilac bush 4 years ago that has never bloomed. It is growing! But not blooming. There is one more spot in the yard we can move it to that will give it more sun, if that is a potential solution. Note: we have never given it fertilizer if you think that would help, too!
Thank you,
Lauren Evans
Franklin County Ohio
Expert Response
Hello,
The most common reason that spring flowering shrubs fail to bloom is improper pruning timing. These shrubs set their buds for the following season during the summer, so if it is getting pruned anytime between late summer of the current year and spring of the following year, the buds are most likely getting pruned off. I would recommend that you not prune your lilac at all during the coming year. Hopefully you will get some flowering in the spring of 2024 and then time your pruning for shortly after the flowers fade.
Lilacs bloom best with 6 or more hours of sun each day, but even with less sun, they should be producing some blooms.
This slide presentation has information about the various types of lilacs that can be grown in central Ohio along with growing requirements. This article from Penn State also has good information about lilac care
It is possible that your lilac could benefit from added nutrients. However, before proceeding with this step, you should get your soil tested to ensure you’re applying the necessary nutrients and not over-applying. Information on getting your soil tested can be found here. Be sure to read and follow all label instructions with any products.
The most common reason that spring flowering shrubs fail to bloom is improper pruning timing. These shrubs set their buds for the following season during the summer, so if it is getting pruned anytime between late summer of the current year and spring of the following year, the buds are most likely getting pruned off. I would recommend that you not prune your lilac at all during the coming year. Hopefully you will get some flowering in the spring of 2024 and then time your pruning for shortly after the flowers fade.
Lilacs bloom best with 6 or more hours of sun each day, but even with less sun, they should be producing some blooms.
This slide presentation has information about the various types of lilacs that can be grown in central Ohio along with growing requirements. This article from Penn State also has good information about lilac care
It is possible that your lilac could benefit from added nutrients. However, before proceeding with this step, you should get your soil tested to ensure you’re applying the necessary nutrients and not over-applying. Information on getting your soil tested can be found here. Be sure to read and follow all label instructions with any products.
Thank you so much - I will read the information you sent.
We actually have never pruned the Lilac bush. I had read that it doesn't need pruned for the first 5 years. Do you think that could have anything to do with it?
I appreciate your help!
Lauren
Hi,
That’s interesting. It can take several years for some shrubs and trees to get established and begin producing blooms, but by year 4 I would expect it to start blooming. That being said, this lilac may just require a little more patience.
I think it’s good that you haven’t pruned it at all and I would recommend not pruning it again this year. It is possible that harsh winter conditions could affect the buds, but since it is fairly close to the house, I would think that would offer some protection.
Here’s another article from University of Minnesota that may be helpful.
A soil test could help uncover the problem. Excess nitrogen in the soil can cause lilacs to put more energy into producing leaves than flowers, so I would recommend starting there to ensure that your soil has the proper nutrients for best flower production.
Your local extension office can help with assessing your soil test and may be able to offer further guidance.
That’s interesting. It can take several years for some shrubs and trees to get established and begin producing blooms, but by year 4 I would expect it to start blooming. That being said, this lilac may just require a little more patience.
I think it’s good that you haven’t pruned it at all and I would recommend not pruning it again this year. It is possible that harsh winter conditions could affect the buds, but since it is fairly close to the house, I would think that would offer some protection.
Here’s another article from University of Minnesota that may be helpful.
A soil test could help uncover the problem. Excess nitrogen in the soil can cause lilacs to put more energy into producing leaves than flowers, so I would recommend starting there to ensure that your soil has the proper nutrients for best flower production.
Your local extension office can help with assessing your soil test and may be able to offer further guidance.
