Did you know that the National Gardening Bureau has designated 2022 as the “Year of the Lilac”? They have a sweet, eerie aroma and are among the easiest shrubs for your landscaping to maintain that bloom in the spring. Find out how to plant, nurture, and prune your lilacs.
About Lilacs
Syringa vulgaris, or common lilac, is prized for its tenacity, dependability, and scent. Lilacs are so hardy that they can live for more than 100 years and frequently outlive the houses they were planted near.
This tiny, multi-stemmed deciduous shrub (or tree) has approximately ten canes and blooms at eye level. The height of a common lilac can range from 8 to 12 feet, depending on the cultivar. The aromatic flowers attract butterflies and make good cuttings.
There are lilac types that come in white, cream, and even pink and yellow, though the blooms are typically lilac/purple in hue (ranging from very pale to extremely dark). Flowers can be solitary or double in number.
Lilacs bloom in northern states from mid- to late spring for around two weeks. However, there are lilac varieties for early, mid, and late seasons that, when cultivated together, guarantee a consistent bloom for at least six weeks.
Lilacs do best in soil that is fertile, humus-rich, well-drained, and neutral to alkaline (at a pH near 7.0). Add compost to your soil to improve it if it is in bad condition. (Learn more about adding amendments to the soil and getting it ready for planting.) Lilacs don’t enjoy having their feet wet and won’t blossom if they are kept too moist, so make sure the planting area drains well.
Lilacs should be planted in full sun, which is defined as having at least six hours of sunlight each day, for the finest blooms.
How to Plant Lilacs
- If you’re fortunate, a friend may offer you a sucker, or offshoot, of the plant’s root system. The sucker will first appear pitiful, but all you need to do is dig a hole, fill it with soil, and then insert the sucker. water next, and then wait. You’ll be rewarded with enormous, fragrant blossoms in 4 or 5 years.
- Lilacs purchased from nurseries can also be planted easily. If the plant was cultivated in a container, spread its roots out as you plant it; if it was balled or burlapped, gently remove the covering and any rope before doing so. Set the plant 2 to 3 inches deeper than it was while it was growing in the nursery and cover the roots with topsoil. in water Then add more topsoil to the hole to finish it.
- Depending on the kind, place multiple lilac bushes 5 to 15 feet apart.
- Apply a layer of compost under the plant each spring, followed by a layer of mulch to keep moisture in and weeds under control.
- If the weekly rainfall is less than 1 inch, water during the summer.
- If lilacs receive too much fertilizer, they won’t bloom. In the late winter, they can manage a few 10-10-10, but no more.
- Spread some lime and thoroughly composted manure around the base of your lilac bush once it has finished blooming. Remove suckers while you form the shrub by trimming it.
Pruning Lilacs
- Since lilacs blossom on old wood, it’s important to prune in the spring immediately following their bloom. You risk removing the wood if you prune later in the summer. A word of advice: It’s time to prune if your lilac flower clusters are getting smaller!
- After bloom each year, cut away any dead wood. Remove the oldest canes by pruning (down to the ground). Take out the tiny suckers. Reduce weak branches until a robust shoot remains. Reduce tall canes to eye level.
- 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 remainder in year three if your lilac is very old and in poor condition. Cutting the entire plant back to a height of approximately 6 or 8 inches is another option for elderly lilacs. Although it sounds dramatic, lilacs are remarkably resilient. This option’s drawback is that it takes some time for the hair to grow back. The lilac will grow back bursting with blooms, so there will be less work and more reward.
- It is important to understand that extreme trimming causes bloom loss for one to three years. For these reasons, a smart pruning program gives the bushes yearly attention in an effort to avoid making dramatic and severe cuts.
The Syringa vulgaris kind of lilacs is the most widely grown and fragrant:
- Try the double magneta variety “Charles Joly” for an early bloom.
- Lilacs in the middle of the season include “Monge,” a deep reddish purple, and “Firmament,” a delicate blue.
- Miss Canada, a reddish pink, and Donald Wyman, a solitary purple, are two late-season beauties.
Syringa x hyacinthiflora, an early-flowering lilac cultivar, opens 7 to 19 days before those of the common lilac. Hummingbirds and butterflies are attracted to its fragrant blossoms.
The cutleaf lilac, a fragrant pale lavender, is one of the common lilacs that may flourish as far south as Zone 9. Common lilacs appreciate cold weather. The beautiful shrub Syringa patula ‘Miss Kim’ has light lilac-blue flowers that eventually become white.
There are tiny kinds for gardeners who simply don’t have the space for the conventional larger lilacs, particularly those in urban settings. Even in a container on your balcony or patio, they will grow.
- ‘Baby Kim’ grows only 2 to 3 feet high (and 3 feet wide) in a pleasantly rounded shape with purple flowers that attract butterflies. Hardiness from Zones 3 to 8 extended.
- Compact lilac ‘Little Lady’ (Syringa x) has dark pink buds that open to lilac-pink flowers and grows to be 4 to 5 feet tall and wide at maturity. Zones 2 to 7 are tough.
- Syringa vulgaris cultivars “New Age Lavender” and “New Age White” were developed for mildew resistance and are quite compact, growing from 4 to 5 feet tall and wide. Hummingbirds and butterflies are drawn to their fragrant blossoms. Zone 4 hardy.
Where should a lilac bush be planted?
When the lilacs begin to blossom, it is a solid indicator that spring has arrived for good. While many people only have a limited knowledge of common lilac (also known as French lilac) shrubs that can reach a height of 15 feet or more, there are now a lot more options available than there were fifty years ago. Some varieties that rebloom enhance the garden’s appeal the entire growing season.
How to Choose Lilacs
The common lilac is what you will most likely find when you go plant shopping. This traditional plant comes in a variety of cultivars and variations, each of which yields fragrant spring flowers in pink, purple, white, or even combinations of those hues. Common lilacs are typically the most fragrant variety of lilac and can grow to be rangy and large.
Rebloomers have arrived in the garden center thanks to recent introductions of hybrids between the common lilac and other shrub-type lilacs. Some of these more recent types are a little less fragrant, but they also tend to be smaller, bloom more frequently throughout the growing season, and have fewer powdery mildew issues.
The tree lilac is another common variety of lilac. It can grow to a height of around 20 feet and blooms with cream-colored flowers in the middle of the summer. Though it doesn’t require much trimming, keep in mind that the tree lilac is a tree, not a shrub.
Where to Plant Lilacs
Lilacs should be planted in full light (at least 6 to 8 hours per day), as too much shadow will prevent them from blooming. Lilacs also prefer moist, well-drained soil that is slightly alkaline.
When to Plant Lilacs
Before the ground freezes in the late fall is the ideal time to plant lilacs. After the earth thaws in the early spring, that is the next ideal period to plant. Lilacs will likely need to be planted as soon as you can locate them at the garden center, which is great; if you choose to do so during a warmer season, they might require additional watering.
How to Prepare the Soil for Planting Lilacs
A soil test should be performed prior to planting since lilacs thrive in slightly alkaline (6.5 to 7.0 pH), moist, well-drained soil that is high in organic matter. Lime must be added to raise the pH if it is below 5.5. It’s time to get the soil ready when you’ve obtained the ideal pH. Improve individual planting holes by mixing Miracle-Gro Garden Soil for Trees & Shrubs in a 50:50 ratio with the natural soil to give lilacs a nutrient-rich start. Iron and phosphorus are also present in this garden soil to promote root development and ward off leaf fading.
Which month is ideal for lilac planting?
Lilac trees grow best in the fall, just after the leaves have fallen and before the ground freezes. Lilacs can be planted in the spring before the buds open. However, springtime is a relatively brief season, therefore transplanting at this time is only advised in regions with really harsh winters.
How long does a lilac shrub take to grow?
Lilacs produce flower buds for the following year after blossoming in the current year, just like other spring blooming plants do. Lilacs should be deadheaded as soon as they finish blooming to promote healthy bud growth for spring flowering.
- Deadhead: For larger plants, use a hedge trimmer or a hand pruner to remove dead flower heads down to a pair of leaves. Shear gently, just removing the dried flower heads.
- Renewal pruning: Renewal pruning promotes the growth and flowering of new stems while distributing more light throughout an older plant. Lilacs that have just been planted often don’t require trimming for 2 to 3 years, and it might take up to 2 years for a lilac to blossom. Lilac stems have a tendency to shadow out new growth at the base of the plant as they enlarge and become more like trees over time.
- Remove a third of the base of the thickest stems with a lopper or handsaw.
- Repeat this each year until all huge stems have been cut off.
- For smaller, thickly branching lilacs like Korean or Meyer lilacs (Syringa meyeri) that have overgrown, rejuvenation pruning is a strategy.
- Use a saw or hedge trimmer to chop the entire plant to the ground in the late winter.
- In the spring, fresh growth will emerge from the root zone.
- For one or two years, the plant might not bloom at all or only sporadically.
- Make sure to choose cultivars that are disease-resistant because powdery mildew is simply aesthetic.
Are lilacs challenging to maintain?
Lilac bushes require little general maintenance because they are low-maintenance shrubs, with the exception of periodic trimming.
Lilacs may withstand a variety of soil types, although they prefer humus-rich, well-drained soil. In order to make a good planting soil for them, incorporate compost into the soil. Lilacs prefer to have their roots kept dry, therefore they should be irrigated properly but sparingly.
It is not required to fertilize lilac trees frequently. However, if there isn’t too much nitrogen present, which would cause insufficient flowering, fertilizing in the early spring may assist promote flowers.
Lilac plants are typically hardy, but occasionally they are plagued by insect pests like borers. Watch for any indications of a pest problem and take fast action to treat it. Sometimes treating insects with a soapy water spray will be adequate. For the care and health of lilac trees, however, it can be essential to completely prune the plant if there are severe infestations.
Pruning is crucial for lilac maintenance. Lilac plants should be well-pruned to reduce the risk of diseases like powdery mildew.
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.
Are lilacs contagious?
Ballistichory, also known as ballistic dispersion, is a unique way that lilacs disperse their seeds that causes the seeds to fly out in a large arc around the plant. The architecture of the seed pod produces this explosive effect by building stress in the woody fibers as they dry, which causes them to break at a planned weak point and fold back to release the seeds. The lilac can now spread its own seeds without the aid of wind or animals thanks to this technique.
What is the duration of a lilac bush’s bloom?
A lilac plant was given to me around seven years ago, and I planted it in our backyard. Each day, it receives several hours of direct sunlight. The leaves have always been a wholesome, mold-free green. It presently stands at about 7 feet. Every year, I eagerly anticipated the blossoms. The first blooms, consisting of two or three clusters of florets, appeared in the spring of 2011. There is only one this spring (now)! Can I do anything to ensure that the plant blooms the next spring?
A: One of the great things that gardeners look forward to each spring is the aroma of lilacs. I don’t think there’s much of a purpose to offer your lilacs significant yard space if they don’t flower. But there are a number of explanations for why they don’t blossom.
- Lilacs prefer a slightly alkaline soil (pH 6-7), even hydration, and lots of sunlight for optimal growth (at least 6 hours). Therefore, you might only get a few or no flowers if your soil is very acidic, it’s dry in the summer when the buds are growing, or your plant doesn’t get enough sun.
- Age: Lilac plants require time to develop before they start to bloom. Therefore, a young plant might not be mature enough to bloom if you have one.
Most plants begin to blossom after three to four years, while others might take up to seven. The first few years’ blooms will be rare, but they should become more numerous over time. If the plant you purchased was in bloom when you got it, then this is definitely not your fault.
- Pruning: Old wood is where lilacs bloom. They develop their buds during the summer so that by late January, they are completely developed and prepared to bloom.
So, two to three weeks after they bloom, or should have blossomed, is the ideal time to prune. Later trimming will reduce or stop flowering the following year. The plant can be kept healthy and flowering with yearly pruning. Remove any broken or dead branches first, then any old, woody ones, any that cross or rub, and then shape. Remove no more than one-third of the plant per year; nevertheless, if the plant is pruned on a three-year schedule, it will regenerate completely in just three brief springs.
- Overfeeding: Sometimes we solve one issue by causing another. Lilac typically doesn’t require further fertilizing. You will get a large, luxuriant plant but few, if any, blossoms if you feed your lilacs, especially if you use nitrogen-rich fertilizer.
Instead of flowers, nitrogen, the first number in a fertilizer indication, 10-5-5, encourages the growth of leaves.
- Transplant shock: Lilacs require some time to adapt. Even if a plant had blossoms when you got it, it is common for plants to take two or even three years to establish themselves and begin to bloom.
If none of the aforementioned scenarios apply to your lilac, you might want to offer the plant some stress, which is something we frequently do to wisteria that doesn’t blossom. A foot or so away from the lilac bush’s base, drive a sharp shovel’s blade into the ground. Cut the plant down, severing the roots on both sides.
I have two inquiries about tulips and daffodils. (1) What should I do with them after they’ve finished blooming? Do you want to base-cut them or deadhead them? (2) Where should I plant new flowers to replace them: immediately next to the bulbs? Do we remove all the green to make room for new blossoms in order to do this?
A: Although no one wants to hear it, the bare greens must be endured if you want to see the spring tulips and daffodils, even when they begin to look unsightly. The greens must stay, but you can tidy up the plants by trimming the flower stems to the ground. They shouldn’t be clipped, tied, or braided since they need to grow and store energy for the bloom the next year. The leaves can be removed from the bed and raked off once they have turned brown.
It is the same as putting perennials among the bulbs as far as that is concerned. Give them room to expand; take care not to disturb the bulbs when digging new planting holes; and, ideally, pick plants that will begin to grow just as the bulbs begin to fade. Daffodils and daylilies are a popular coupling that offers an excellent circumstance since the daylilies mature and cover the daffodil greens just as they begin to look pretty ragged.