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Growing Lilacs
How to Plant, Grow, and Care for Lilac Shrubs
How to Plant, Grow, and Care for Lilac Shrubs
Huge blooms, wonderful scent.
Wally PatrickWho doesn’t love lilacs? The ideal lilac shrub has about 10 canes and produces flowers at eye-level—all the better to enjoy that sweet, haunting fragrance.
Lilacs do come in seven colors, but most are familiar with the common lilac, Syringa vulgaris, which blooms in the northern states for 2 weeks in late May. However, there are early-, mid-, and late-season lilacs, which, when grown together, ensure a steady bloom for at least 6 weeks.
Lilacs are hardy, easy to grow, and low maintenance. They can grow from 5 to 15 feet tall, depending on the variety. The fragrant flowers are good for cutting and attractive to butterflies.
Planting
- Grow lilacs in fertile, humus-rich, well-drained, neutral to alkaline soil (at a pH near 7.0). If your soil is in poor condition, add compost to enrich. Learn more about soil amendments and preparing soil for planting.
- Select a site where your lilac will get full sun—at least 6 hours. If lilacs don’t get enough sun, they will not bloom well.
- Make sure the site drains well. Lilacs don’t like wet feet and will not bloom with too much water.
- Plant in either spring or fall, although the latter is preferred.
- If you’re lucky, a friend will give you a sucker, or offshoot, of the root system of one of his plants. Your sucker will look pathetic at first but just dig a hole, backfill it with soil, and stick the sucker in. Then water and wait. In 4 or 5 years, you’ll be rewarded with huge, fragrant blossoms.
- Transplanting lilacs from a nursery is also easy. If it’s container-grown, spread out the roots as you settle the plant into the ground; if it’s balled or burlapped, gently remove the covering and any rope before planting. Set the plant 2 or 3 inches deeper than it grew in the nursery, and work topsoil in around the roots. Water in. Then fill in the hole with more topsoil.
- Space multiple lilac bushes 5 to 15 feet apart, depending on the variety.
Care
- Each spring, apply a layer of compost under the plant, followed by mulch to retain moisture and control weeds.
- Water during the summer if rainfall is less than 1 inch per week.
- Lilacs won’t bloom if they’re overfertilized. They can handle a handful of 10-10-10 in late winter, but no more.
- After your lilac bush has finished blooming, spread some lime and well-rotted manure around the base. Trim the bush to shape it, and remove suckers at the same time.
Pruning Lilacs
- Lilacs bloom on old wood, so it’s critical to prune in the spring right after they bloom. If you prune later in the summer, you may be removing the wood. Here’s a tip: If your lilac flower clusters are getting smaller, time to prune!
- Every year after bloom, remove any dead wood. Prune out the oldest canes (down to the ground). Remove the small suckers. Cut back weak branches to a strong shoot. Cut back tall canes to eye height.
- If your lilac is old and in really bad shape, remove one-third of the oldest canes (down to the ground) in year one, half of the remaining old wood in year two, and the rest of the old wood in year three. Another option for old lilacs is to chop the whole thing back to about 6 or 8 inches high. It sounds drastic, but lilacs are very hardy. The downside to this option is that it takes a few years to grow back. The upside is less work and more reward, as the lilac will grow back bursting with blooms.
- It must be recognized that severe pruning results in the loss of blooms for one to three years. For these reasons, a wise pruning program aims to avoid severe and drastic cuts by giving the bushes annual attention.
Pests/Diseases
- Prone to attack by slugs and snails.
- Powdery white mildew may appear after a summer of hot, humid weather. It may be unsightly, but it does no harm. Ignore it.
Recommended Varieties
The most common and fragrant lilacs are of the S. vulgaris variety:
- For early bloom, try ‘Charles Joly’, a double magneta.
- Mid-season lilacs include ‘Monge’, a dark reddish purple, and ‘Firmament’, a fine blue.
- Late-season beauties include ‘Miss Canada’, a reddishpink, and ‘Donald Wyman’, a single purple.
Although common lilacs love cold weather, a few thrive as south as Zone 9, among them the cutleaf lilac, a fragrant pale lavender. Syringa patula ‘Miss Kim’ is a graceful shrub with pale lilac-blue flowers that fade to white.
Wit & Wisdom
- To improve the flowering of lilacs, keep the grass from growing around them. A 16- to 24-inch circle of landscape cloth placed around the bushes and covered with bark or stone will keep the grass down.
- Force a winter bouquet from cut branches of lilac. Bruise the cut ends and set them in water. Spray the branches frequently. Keep them in a cool place until they bloom, then move to a warmer area for display.
- Poet Walt Whitman thought of lilacs when Abraham Lincoln died:
“When lilacs last in the dooryard bloom’d … I mourn’d, and yet shall mourn with ever-returning spring.” - Lilacs supposedly symbolize the joy of youth. Learn about more flower symbolism here.
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Reader Comments
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Lilac buds opening in fall
Hello I got a lilac bush that I transplanted 4 years ago and it bloomed good last year and I noticed it made new buds in July and in late September the buds broke open and the flower buds for this spring has opened and froze so what caused this and what can I do to prevent this from happening again?
preventing bud freeze
You need to protect the lilac from early or late-season freezes by covering them. You can use plastic, or bed sheeting, burlap, tarps, or whatever is large enough BUT you have to keep the covering from touching the lilac. Contact with the cover means contact with the freeze, so avoid contact. Use frame (often homemade) or stakes or, for example, a ladder and drape the cover over the plant. Clothes pins will sometimes hold the cover in place. You should not need to leave the cover on if no freeze is forecast.
New bushes
I got a new, small, bush last year(miss Kim) and a mouse or mole routed through the roots leaving it the appearance of being dead. We planted what was left again with little hope but it did start putting out leaves about half way through the summer. Since we believed it was dead we got another Miss Kim and it seems quite healthy but I am not sure if we should be wrapping it for winter or if that would encourage a mouse or whatever to move in again or if lilacs even need/want to be protected like that? Help for a newbie to lilacs?
Lilac bush
I have a very old lilac bush my mothers she got it from my grandmother well it has something on its trunk blueish green scales and dying what can I do to save it and the leaves are powdery
Lilac bush won't grow
I bought a lilac bush at a fair about 7 years ago. I
t was about 4 feet tall. My son planted in a sunny place that gets sun all day. It is healthy and gets very small blooms every year but looks like it hasn't grown an inch since it was planted. Our town is known for lilac's and they grow all over town. I don't understand why mine won't grow.
4 foot tall lilac
It’s possible it’s a miniature variety. Are leaves 3 inches or about 1 inch. If no longer than approx 1 inch. It’s a miniature variety
My lilac is not blooming and not growing like I think it should.
My lilac is about 5 years old and has never bloomed and although it has grown, not as it should have. I would say it is about 3 to 4 foot high for a 5 year old bush. I planted it where i had removed an above ground pool and was wondering if the sand that was used to level the pool on installation could be the reason. I don't see any sand, so it has worked it's way into the dirt. Any suggestions?
Yellowing leaves and sparse
I am trying to find out what is going on with my old fashion lilac. I started it from a sapling about 15 years. It has four off shoots that are probably 10 years old. This year the flowers again where huge and gorgeous. But I have now noticed the density of the leaves is really sparse they are yellowing with some brown spots. I don't know what to do.
Lilac leaves have brown spots
Just planted in spring but now leaves have brown spots - help
seedlings
I planted seedlings 3 yrs ago, some are 6' tall and some 3' tall, I haven't pruned them yet and haven't had any flowers yet, should I prune them back a little will that help?
Thank you
Frank
no flowers...
Are you fertilizing these plants? Too much nitrogen will favor leaf formation over flowers. Do not fertilize. They do like soil with a pH of 6.0 to 7.5, though. Do a soil test—even a simple one—and see if the pH is within the range.
Lilac bush
My lilac bush is tall and skinny. It looks super healthy and blooms beautifully but I don't know how to get it to bush out. All the lilacs I have ever seen get nice and round and full....Mine looks like a pole... what do I do?
how to make a lilac spread
As you suggest, this is not usually a problem. So the solution provided by the Cornell U coop extension may seem like an odd answer but here goes: prune it. (Have you ever prune it?) Specifically, the coop ext says, You can prune overgrown lilacs (if relatively healthy) down to the base of the plant in late winter/early spring. This action will force new vigorous growth and put you back on the road to having a beautiful, properly proportioned shrub. Blooms may be sacrificed for two to three years while the shrub is reestablishing itself. Once rejuvenated, maintenance pruning should be performed on an annual basis.
This sounds severe, but promising, if you can wait for the regrowth. You might also consult the nursery you purchased it from (or any nursery) to see what they recommend.
Lilac Roots and Leach Lines
Will lilac roots damage the leach lines from my septic tank? If so, how far from them do I have to plant the lilac to keep the roots away?
Thank you
lilac to leach lines
There are some general standards re distance; lilacs that 8 to 10 feet from water and sewer lines should be fine.
Lilac roots will probably not break intact pipes, but they could be drawn to pipes that leak.
For more information you could contact your town inspector or a nursery person.
lilacs vs morning glories
can I plant a lilac bush close by morning glories or with the roots bother the lilac bush
Morning Glories
Morning glory roots shouldn’t be an issue for lilacs, since the lilac roots will reach much deeper than the morning glories. Plus, morning glories are annuals, meaning they die back at the end of the growing season and will no longer be a competitor to the lilac.
lilac suckers
I am putting a bed of rocks near a thriving lilac bush. I do not want the suckers to come up under, through the ground cover and into my bed of rocks. How deep would I have to bury a barrier? 6-8 inches deep enough? Or is there any way to keep the suckers controlled and in a confined area? If I cut suckers off each year, to keep in a confined area, will they continue to spread out farther?
root barrier
Hopefully someone can share a little insight. I've planted several lilacs along my back fence. I was in a quandary as to what to do regarding the invasive ground cover sneaking under the fence from my neighbors yard. I have attempted to pull it out , but presume that it will return repeatedly. Consequently I chose to plant each of my five lilacs in a circular barrier made from half a large trash barrel. The barrels are approximately 22 in in diameter and fourteen to sixteen inches in height. The hope is to allow the lilacs roots to grow below the barrier and spread as the plant matures while keeping the invasive ground cover with more shallow roots separate. Hopefully I'm not confining the lilac roots if they tend to grow more shallowly themselves. Any thoughts out there?
lilac in a bucket
Almost everything works for a while. You are removing the bottom from the barrels, right? If you do not, you will confine the lilac roots and eventually they will cease to thrive (we’re guessing that would happen before the barrels break down to release the roots). And you’re setting the barrels deep enough to have the rim at ground level? Or are the barrels going to be above ground, shielding 14 to 16 inches of lilac trunk?
You do not name the ground cover but you are probably correct in expecting it to return, despite your pulling it out. (There is a saying about ground covers: the first year it sleeps, the second year it creeps, the third year it leaps.) If the barrels are aboveground (not sunk to the rim) the ground cover roots could eventually make their way past the barrel barrier. Could you sink edging between you and your neighbor? A healthy lilac will send out suckers, too. Whether these appear within the perimeter of your barriers or reach from the depths and “pop up” outside of the barrier remains to be seen.
Another thought is to mulch the lilacs. A thick (3 to 4 inch) layer should help to deter or slow down the ground cover.
Hope something here helps.
The idea of sinking a barrier
The idea of sinking a barrier between yards is a great, I'm going to try this too!
Can we still prune our lilac bush
We still have the dead blooms on our bush, and some spindly branches, with no growth (not even leaves). We moved our lilac bush, 2 years ago, and it has grown bigger and better, and this year we have noticed a 2 foot tall, addition coming up! It’s all nice green leaves, which has confirmed that our move/transplant that we did was the right thing to do. Whoever planted before we lived there, placed it in a corner, about 2 feet from a short wooden fence. Since we moved “her” out of the corner and away from the fence,it’s responding well. It gets plenty of sun, has a weed/grass cloth, all around it, and we water it when necessary. The one thing we have no experience with, is pruning. I would love to see it produce more blooms, as well as “fill”, out, but we don’t want to do it wrong or, probably, too late. Can you help us?
when to prune
The best time to prune is after the bloom passes. See above also (repeated here for expediency):
Lilacs
Do i cut off dead lilacs when they all die?
dead blooms
If you are referring to the flowers, yes, you can do that.
Great grandmothers lilac lost it's leaves...
We have transplanted our great grandmother's lilac quite a few times and now it is with me in NC. It was planted in September but now has lost all its leaves... I have read it may have too much nitrogen, so I am feeding it bone meal and phosphorus. But have read lots of other info on this... Can you add some helpful input? Thanks in advance for any help you can give me... It is the original plant from the 1910's and very important to me!
helpful input
Most of our helpful input is above on this page. Consider the suggestions for compost in spring and well-rotted manure after bloom and other care tips. Great grandmother would be happy with your success.
Young lilacs, lovely green leaves that are tinged red
Hello. I received bare root lilacs from the Arbor Foundation last year. Planted them. seem fine. They are about a foot/foot and half now and very green leaves. BUT, I noticed last night some of the leaves are sort of tinged a darker red. The leaves look healthy..not dry...not curled....just sort of edged in red. Any thoughts? I am in SE Wisconsin.
Thanks
Red-Tinged Lilac Leaves
Hi Denise,
Red-tinged leaves can be a sign of a nutrient deficiency. The exact nutrient that the plant is lacking is hard to identify, so a good cure-all is to amend the soil with aged compost. We hope this helps!
Zone 7 with acidic soil
I live in Georgia and the soil is quite acidic, can I grow lilacs in a container? If I can, how big a container should I use and would bags of top soil be alkaline enough? What lilacs would be best to grow in a container?
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