Ask a Question
Notify Me On Question Update
Email this Question
I want to plant a lilac hedge. I've never done lilacs before - how far apart should I plant them? Can I do a double row for a thicker hedge? If so, how far apart should the rows be? How fast do they grow? Do they need special care (they will be pretty close to a fairly busy road)? Can I plant them now, or should I wait until it's a little warmer? What are their fertilizer and water requirements? Will they be useful as a bit of a wind- and soundbreak? Thank you.
Rate This FAQ
This is in answer to your question about growing lilacs: Lilacs are a good choice in our area for a beautiful hedge but they need good air circulation and 6 to 8 hours of full sun each day for good bloom production, so I would not plant a double row. Plant a single row with each plant about 3 to 6 feet apart to result in a 6- to 8-foot tall hedge. Bareroot shrubs should be planted when dormant (in late fall or early spring), but if you get your plants in containers, the timing is not so critical because they will have a fairly well developed root system for uptake of water.
There are hundreds of varieties of lilacs. I will assume you are talking about the common lilac (Syringa vulgaris), in which case you can expect a moderate rate of growth of up to 1 foot per year. Lilacs need well-drained soil, so if your soil is clayey, you can amend your soil with peat moss to a depth of 6 inches prior to planting to improve soil drainage. You need not add fertilizer at the time of planting if you have good organic soil. If not, add a slow release granular fertilizer (5-10-5) or (5-10-10) about one month after planting and water it in well. Also, mulch around the base of your plants with shredded bark or wood chips to keep roots cool, preventing evaporation of soil moisture, and reduce weeds.
You should water your plants deeply about once a week after planting to encourage good root growth. Once established, your lilacs will require only occasional deep watering. Lilacs produce flowers on last year's growth, so wait until just after their blooms fade to prune. Prune out old canes at their base to allow greater access to light and to keep your plants healthy and vigorous. You don't need to remove spent flowers after bloom, and never "top" your lilac -- this produces fast, unsightly growth that will ruin the natural shape of your plant.
Lilacs can make a lovely and fragrant wind and sound barrier.
For more information, check out the "Growing lilacs" fact sheet at
Submit Your Suggestion
Other Questions In This Topic
- I have a mature elm in my backyard that was probably planted when the house was built in the 70's. We bought it 3 years ago and I have noticed that something is eating away at the bark. There is a reddish-brown streak (almost like what you would see in a human that has blood poisoning) that runs up the bark. I cut off one of the lower limbs that the problem had progressed to. The bark is very "mushy" and looks decayed. Chunks of bark fall off at the affected areas. I cannot see any bugs that may be causing this but I suspect that is the cause. This tree has 2 main branches that extend from the bottom and this is where the main damage seems to be. I am concerned that the tree could "split" at this point if it becomes weakened. I need to know the cause and treatment.
- I think I have Johnsongrass invading my back lawn. I has sprayed the usual Crabgrass/lawn grassy weed killer on it and it is still taking over my entire lawn. What can I do?
- We have Ray wood ash trees around our home and last year they were topped by hormworms. What do you suggest?
- Our golden delicious apple tree drops fruit through the entire season. What are we doing wrong? It is located in our garden area and gets plenty of water. Thank you for your help.
- My new austrian pines planted in the fall are looking pale in color and a lot of needles have fallen off. Also, my older austrian pines are looking the same way. What do they need? The soil has a lot of clay and is quite alkaline. My new spruce in the same area is doing great. What do the pines need?
- When is the best time to spray a cherry tree for worms?
- My petunias are horribly sticky - I assume thrips are in control although I have tried to keep them washed off (insecticidal soap) and sprayed with a systemic (orthonex). Is there anything else I might try? Would a dormant oil spray work, and if so when would I use it? Also, there are small worms that are probably chomping the blossoms. What would work to prevent or kill them? How do worms can get into my flower boxes, that are at least 6 feet off the ground?
- I have mexican fruit flies that lay eggs and hatch larve in my apples and cherries. They are larger than reqular fruit flies and have black and white striped wings. When should I spray? What should I spray with?