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We have a large lilac bush that was transplanted about 10 years ago. It is quite healthy and seems to be thriving but it has NEVER bloomed since we transplanted it! Anyone have any ideas as to why this may be happening and if there is anything I can do?

Thanks!

You might want to cut it back some , the old woody stems, and fertilize. If I remember correctly it flowers on old wood so it wouldn't bloom the next year after pruning.

I will try that, thanks!

You didn't say where it is. Is it in full sun?

Is it in the middle of a lawn? Do you fertilize the lawn? With what? Lawn fertilizer is high nitrogen, which is great for lawns because you just want "leaves." But high nitrogen fertilizer tends to stimulate leaf growth at the expense of flowering.

Sorry about that, it's in full sun, not in my lawn so nitrogen shouldn't be an issue. It is about 10 ft. between a dogwood and Japanese maple.

I have a dwarf lilac and had the same problem. I would get 1 or 2 flowers and thats it.I was pruning it into a circle shape and doing it at the wrong time.Lilacs produce the flowering points through the growing season.I now prune in the begining of summer after the flowers fade and leave it alone. its been full of flowers the last 2 years

Yes indeed, I should have asked about pruning. If you prune your lilac in the spring, you will never see a flower, since you would be pruning off the buds.
Do any pruning you need to (they don't need a lot) right after it blooms. By early fall it is setting next year's buds.

Once you do get flowers, it is important to dead head them-- clip off all the flowers once they fade, before it can set seed. Lilac seeds are big and heavy and don't travel far from the mother plant. So in order to reduce competition amongst all the seedlings, in nature lilacs tend to bloom heavily only every other year. The in between years it will produce just a few flowers. Stopping them from setting seed allows you to have a shrub full of blooms every year.