Lilac trees don’t require much care as they develop, but a little bit of maintenance will enable them to reach their maximum size and produce more of those wonderful blooms. The following are some steps to take when caring for lilacs:
- Apply a thick layer of mulch every year to keep moisture in and keep weeds under control.
- The common lilac trees should not be watered until the top is completely dry.
- Sparingly fertilize your lilac plants. A quality fertilizer applied in the late winter will be adequate for the remainder of the year.
- When it comes to caring for lilacs, correctly pruning them comes first on the list of things to do. Once the blossoms have stopped, trim them. They get stronger than previously as a result of this.
- The plant will produce more blossoms if you deadhead lilacs. Additionally, it will enhance the appearance of the plants.
- Keep grass away from the lilacs’ roots to encourage better flowering.
How are lilac bushes taken care of?
The ideal season for planting lilac plants is spring or fall. Make the hole deep and wide enough to fit the lilac’s roots, and then plant it with their spread vertically in the ground. Even if you intend to use them as privacy hedges, you should leave at least 5 feet (1.5 m) between each lilac bush you plant to avoid overpopulation.
A location with lots of afternoon sun and well-drained soil is ideal. Lilac bushes need adequate drainage, so wherever possible, planting lilac shrubs in somewhat higher locations is advised. Lilac bushes should be planted, then given plenty of water and a coating of loose mulch. Keep the mulch light enough not to hold too much moisture, yet thick enough to keep out weeds and preserve some moisture.
Do lilac bushes need to be pruned?
An old, overgrown lilac was one of the few plants that endured my garden restoration. The fact that it obscured my neighbor’s garage and, more importantly, sported steel-blue double flowers, led me to rescue it. Although the blossoms on this shrub were both lovely and fragrant, it was difficult to appreciate them because there were so few of them. I decided to go with a rejuvenation pruning because I knew there was no reason to give up on this long-neglected plant because lilacs can handle severe pruning.
On stems that are no older than five or six years, the common French lilacs (Syringa vulgaris cvs.) yield the most and the largest flowers. The flowers get fewer, smaller, and farther away as the stems get older. A lilac, however, may reliably produce blossoms for decades with the right trimming. The method you choose will depend on how old your shrub is. Plants are maintained annually to keep them healthy. A more drastic trimming may be necessary for lilacs like mine that have seen better days.
Lilacs should be clipped annually to encourage healthy stem development and strong growth that improves flowering. Cutting sick, deformed, and unproductive stems to the ground constitutes annual pruning. I thin and cut back some stems as well to promote healthy, evenly spaced growth. To prevent them from growing too far away from the center of the plant, I also pruned a few of the new shoots that emerged from the roots. I left a few inches between each stem to prevent crowding. Since they produce the most, I maintain the pencil-thick shoots that extend all the way to the ends of the branches. Small, twitchy growth is unproductive and won’t blossom. This growth can indicate an excess of aged, unproductive stems or too much shadow. Remove stems as soon as possible after blossoming, or in late winter if you don’t mind losing a few blooms. Cut off stems and shoots at or just below the soil line.
Dwarf lilacs rarely need pruning
Both the “Palibin” Meyer lilac (Syringa meyeri “Palibin”) and the “Miss Kim” Manchurian lilac (Syringa pubescens ssp. patula “Miss Kim”) are twiggy-habiting, somewhat small lilacs. On these types, just deadheading is needed in terms of pruning. You can prune some of the older stems as the plants get older to make place for younger, more robust stems. In contrast to regular lilacs, these plants hardly ever spread out of control. They might never need to be entirely regenerated if you only undertake a tiny amount of trimming every few years.
After the blooms have faded, deadheading, another aspect of annual maintenance, should be carried out as soon as feasible. Just above the two new shoots that slant out from the stem that stopped with the old bloom, the base of the old flower cluster should be cut off. The new shoots will develop throughout the course of the summer, produce flower buds, and culminate in a cluster of flowers the following spring. While not as crucial as the annual thinning, eliminating the old blossoms enables the plant to focus more of its energy on developing robust branches and flower buds. In June, I deadhead and thin my plants as needed.
While performing this yearly maintenance, I occasionally come upon a young, robust shoot that may be getting too tall but is still a good, productive stem and is a candidate for tipping off. I cut the wasted flower’s entire top stem back to one or two side shoots at the desired height rather of just cutting it off at the base. The side shoots that are now near the top of the bush are encouraged to grow vigorously and develop flower buds for the following year by this cut, which also aids in shrinking the shrub.
My own old, overgrown lilacs need more severe pruning. I went outside in the early spring before growth got going to get a good look at the bush. I looked to see if the plant had been grafted before I began chopping. I immediately cut it down to the ground as it hadn’t (for a grafted plant, see the panel below). I recognized that this drastic trimming would result in the plant losing part of its aesthetic appeal for a few years because lilacs bloom on the growth from the previous season. However, I was also aware that the reward—more blossoms and a stronger plant—would be worthwhile.
It’s crucial to nourish the plant after rejuvenation pruning with compost, composted manure, or a balanced chemical fertilizer and to make sure the soil pH is close to neutral, which lilacs appreciate. In the upcoming years, these supplements and some high-quality mulch will help to encourage vigorous new growth and enhanced flowering.
Has your lilac been grafted?
If your lilac has been grafted, check it out before you start making cuts to the stems. Grafting is a method of plant multiplication in which the scion, or branch, of one species is joined to the rootstock, or stem, of another species. This is typically done to enhance a plant’s look or traits. A graft union, where the cultivar’s scion wood joins the rootstock several inches above ground level, should be obvious. An apparent change in the bark from the rootstock to the scion’s bark, as well as a little swelling at the graft union, are things to watch for. If your plant has been grafted, all of your cuttings must be made above the graft union, and you must prevent shoots from the rootstock from developing into new flowering stems. Flowers of the desired shape or color will not be produced by shoots that emerge from the rootstock.
When should a lilac bush be pruned?
All lilacs should generally be clipped right away in the spring after they have finished blooming. Lilacs set their flower buds for the following year immediately after the current year’s flowers have faded, therefore trimming later in the summer or fall will result in the removal of most or all of the blossoms for the following year. The larger common lilacs as well as the shorter or more “shrub like” cultivars are all subject to this timing guideline. While the “when” of lilac trimming is rather simple, the “how” is a little more difficult. For the time being, we’ll refer to lilac pruning as either maintenance pruning or rejuvenation pruning to keep things simple.
How are lilac plants kept in bloom?
- Keep the grass from growing around lilacs to enhance blossoming. The grass will be kept down by placing a 16- to 24-inch circle of landscape fabric around the bushes and covering it with bark or stone.
- Cut lilac branches should be forced into a winter bouquet. The cut ends should be bruised and placed in water. The branches need frequent spraying. When they bloom, keep them in a cool location; after that, move them to a warmer location to show.
- When Abraham Lincoln passed away, poet Walt Whitman had lilacs in mind:
I cried and will continue to cry as spring keeps coming back as the lilacs in the dooryard bloomed for the last time.
- Lilacs are said to represent youthful enthusiasm. Discover more about floral symbolism here.
Should I prune my lilac bush’s dead flowers?
The removal of spent flowers to encourage new blooming—deadheading—is a crucial part of lilac maintenance. Lilacs should be deadheaded as soon as the flowering is finished to allow the plants to grow robust, healthy buds that will flower vivaciously the following year. According to the University of Minnesota Extension, you can use a hand pruner, but larger plants could require a hedge trimmer. Only the dead blossom should be removed; the plant should still have two leaves.
According to the Chicago Botanic Garden, you should prune lilacs at the same time as you deadhead them since they set the blossoms for the following year quickly after flowering. By doing this, you can prevent damaging or removing the developing buds. Three to four years after planting, you should start pruning lilacs. It might be necessary to trim back overgrown lilacs to just a few inches above the ground. Winter is the ideal time to complete this. In this instance, it will take the shrub one or two growing seasons to start blooming once more.
Can you grow lilacs with Miracle Grow?
3. Take the plant out of its pot and place it in the hole. Make sure the top of the root ball is about an inch or more above the soil surface.
4. Apply the soil mixture all the way around the root ball, pressing it down firmly.
5. Take a long drink.
6. Mulch the area you just planted to a depth of 2 inches, being careful not to pile mulch up against the base of the plant. This will help keep the soil moist and prevent weeds from sprouting by denying them access to sunlight.
How to Water Lilacs
After planting, monitor your plants frequently, and water them once or twice a week, or anytime the top inch of soil becomes dry. While watering, count to 10 to make sure you’re providing each lilac plant with enough moisture. (If the plant becomes too dry, the leaves will start to droop.) You can reduce watering to every other week once plants have been planted and have had a few months to establish themselves. Lilacs won’t require additional water during the second growing season or later unless there hasn’t been rain in your location for a month or more.
How to Feed Lilacs
Lilacs should be fed Miracle-Gro Shake ‘n Feed Flowering Trees & Shrubs Plant Food after they have bloomed in the spring to encourage the development of robust roots. This plant food is jam-packed with nutrients for your plants, including kelp, earthworm castings, feather meal, and bone meal. These ingredients nourish soil bacteria, which in turn break down organic matter into nutrients for your plants.
How to Help Prevent Disease Problems with Lilacs
Powdery mildew is the main problem with lilacs, especially common lilacs. What’s the best approach to prevent this? Purchase and plant lilac cultivars that resist powdery mildew (check the plant tag or online description). Lilacs benefit from being planted in areas with good airflow. This fungus disease won’t respond to spraying, and it will finally go away on its own.
How to Deadhead Lilacs
Be sure to deadhead young lilacs as they start to bloom (this could take a few years!). Deadheading involves clipping off faded flowers at the base as soon as they start to droop and fade. In response, the plant will use more energy developing new flower buds for the upcoming spring.
How to Prune Lilacs
Although the newer, smaller lilac kinds require less trimming than the enormous conventional lilacs, all lilacs will grow more effectively and bear more flowers with regular pruning. Here are a few possibilities:
- Cut an older lilac shrub to 8 inches above the ground in late winter (March or April), then let it grow out if it isn’t flowering despite receiving plenty of sunlight. The following March, choose 8 to 10 of the best-looking stems, and reduce them by half. Trim the remainder to the ground. The following year, new blossoms should appear.
- Selectively prune 1/3 of the branches all the way back to the ground each year to revive shrubs that aren’t flowering well instead of chopping the shrub all the way down.
- Cut back branches to reduce size as soon as the shrub’s flowering has finished.
How far can lilac bushes be pruned back?
Cutting off the tops of stems that have grown out of control is frequently insufficient when pruning lilacs. It is typically preferable to remove the entire stem. The best way to trim lilacs is with clippers. To avoid spreading and promote later blooms, remove spent blossoms right down to the stems. Three-quarters of the branches should be pruned. Remove any shoots that are emerging from the main trunk and are growing close to the ground. Lilacs within the inner branches may need to be trimmed in order to increase air flow or let more light through.
However, it may be essential to prune the entire bush or tree to approximately 6 or 8 inches (15-20 cm) above the ground if lilac shrubs are already too big or starting to look unpleasant. Remember that it takes around three years for flowers to grow after the entire bush has been removed, so you might have to wait.
What distinguishes a lilac bush from a lilac tree?
Lilac bushes (also known as shrubs) are characterized by their numerous woody stems that emerge from the plant’s base. In contrast, the trunk of the majority of lilac trees is the only woody stem. However, your neighborhood garden center might also sell shrub lilacs that have been grafted onto a single stem to give them the appearance of miniature trees.
The choice between a lilac tree and a lilac bush is typically determined by the amount of space available. Lilac bushes come in a range of sizes and can be placed in more compact areas of a garden. A lilac tree requires space to reach heights of 20 feet and widths of 15 feet. Both require sunlight to bloom well.