When Do Lilacs Flower

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’ has a lovely rounded shape, only grows 2 to 3 feet high (and 3 feet wide), and has purple flowers that draw 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.

When does the lilac flower bloom?

A lilac in full bloom is a magnificent sight, and it smells great. Lilacs are one of the best flowering shrubs and a staple of the spring landscape in northern and colder climes. These hardy shrubs have been developed to satisfy the requirements of all gardens since they are simple to cultivate, strong as nails, resistant to deer, and largely free of main pests.

  • Lilacs can bring color and scent from April through June, depending on where you live and the types you pick. It is possible to have two months of spring blossoms by making wise plant choices, especially if the weather is chilly. However, a warm spring will cause flowers to blossom earlier than usual, cutting the blooming season by a few weeks.
  • Choose Syringa x hyacinthiflora (Hyacinth Syringa) for the earliest blooms; they begin blooming in mid-spring, about 7–10 days earlier than Syringa vulgaris (Common Lilac).
  • The longest flowering species is the common lilac, which can last up to a month depending on area and cultivar. It often blooms in late spring and has the biggest, most fragrant flowers.
  • With varieties like Littleleaf Lilac (Syringa microphylla) and Japanese Tree Lilac, you may extend the lilac season into the summer (Syringa reticulata).
  • Choose a reblooming lilac if your space is constrained and you can’t enjoy several lilac kinds. These lilac bushes do not only bloom for a brief period in the spring. They extend their stay by repeatedly blooming throughout the summer and the fall, adding beautiful color and fragrance to the garden.
  • 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. But because fresh roots have a head start in April before the shrub starts to leaf out, lilacs planted in the fall typically have a higher chance of surviving.

Why hasn’t my lilac bush bloomed?

A. There are a number of potential causes for your lilac’s failure to blossom. Lack of sufficient sunlight is the main culprit. Lilacs (Syringa) should be planted in an area with at least six hours of direct, bright sunlight per day. They can withstand a wide range of moisture levels as long as they are grown in soil with good drainage.

If your lilac is clipped at the wrong time of year, it might not blossom for another reason. Lilacs bloom in the spring on the growth from the previous year, and soon after, they begin to form the buds for the following year. Within a few weeks of the plant blooming, pruning must be done simultaneously with the removal of the wasted flowers in order to prevent the removal of the buds for the following year. A late freeze can harm flower buds on types that bloom early.

Lilacs have a tendency to mature into overgrown, leggy shrubs with minimal foliage at the bottom. When this occurs, it might be required to prune them to within 12 inches of the ground in order to completely rejuvenate them. When the shrubs are dormant in late winter, this should be done. Lilacs benefit from this repair, although their blooming cycle will be hampered for at least one season. Lilacs can receive a rejuvenation pruning over a two-year period to stop the interruption of bloom cycles. Half of the shrub’s stems should be hard pruned the first year, and the remaining stems the following year.

Lilacs do not consume a lot of food. Excessive fertilization, particularly nitrogen fertilizer, can frequently promote luxuriant vegetative growth at the expense of flower development. A lilac’s failure to bloom could potentially be due to its proximity to turf that receives frequent fertilization.

How many times do lilacs bloom each season?

The late lilac is the leading contender for a long-lasting lilac that will bloom profusely throughout the warmer months of the year (Syringa villosa). As its name suggests, it blooms later than other types and produces fragrant white, pink, rosy lilac, violet, and even crimson blossoms. This lilac bush only has one summer bloom and enjoys direct sunlight.

Consider a reblooming lilac for your garden if you want consistent flowers. Lilacs that rebloom will first bloom in the spring, then rest until summertime when they will blossom once more. After their spring rest, certain types, such as the Bloomerang dark purple, will continue to bloom until the fall. Look for the Josee reblooming lilac (Syringa Josee), which intermittently flowers throughout the summer and into the fall, if you live in a warmer climate.

Do lilac plants have two blooming seasons?

Compared to other lilac trees, bloomerang lilac trees are more compact, reaching a short height of 4-6 feet tall and a spread of 4-6 feet, giving them a pleasing, rounded appearance. Their long, arched branches bear their veined leaves, which are bright green for the majority of the year until turning yellow in the fall.

The characteristic 4-petaled, 4-6 inch deep lilac-purple blooms on bloomerang lilac trees appear starting in May, cease blooming in June, and then return in July through the first frost of the year.


With tall, arched branches, a compact and rounded shape, and rich green foliage that turn golden in the fall. Four spread petals, 4-6 inch, lilac-purple flowers that bloom in the spring and later in the summer.

How can I force my lilac to bloom?

Although there are several potential solutions to this problem, pruning might hold the key. Lilacs blossom on the growth from the previous year, so it’s crucial to cut them as soon as the spring blooming is through. Pruning a lilac in the summer, fall, or winter may result in the removal of buds that would have bloomed the following spring.

After the spring bloom, try to only lightly prune the plant. If you want to avoid delaying the next bloom by drastically pruning your lilac shrub, simply remove the oldest and heaviest branches and trim the inner branches to make room for sunshine to enter the bush.

Take into account the age of your lilac bush, which by this point may have evolved into a tree. On younger wood, lilacs bloom at their best. If the majority of your lilac’s structure is old, decayed wood, blooms may be scarce. An elder lilac can require rejuvenation pruning, followed by a two- to three-year wait before it can bloom fully again.

Lilac bushes’ lifespan is how long?

Lilacs are renowned for their longevity and hardiness.

Numerous lilac shrubs reach ages of greater than 100. They frequently outlive the residence of the gardener who planted them due to their extended lifespan. As a result, if you’re driving along a country road and come across a few what appear to be random lilac bushes, it was probably a farm or house a century ago.

Try growing lilacs in your garden if you haven’t already. They not only return every year, but they also put on a display for the senses with vibrant blossoms and enticing scents. Lilacs have a lot to offer, and learning about their history demonstrates just how unique these plants are.

When should lilacs be pruned back?

A lilac shrub needs to be pruned every year once it has reached the age of two. Early summer is ideal for cutting grass because the flowers have already flowered and withered. Here are some tips for taking care of lilac shrubs and trees.

Lilacs produce the flower buds for the following season in the early summer, right after their blooms have faded. You run the danger of removing the budding buds if you delay trimming until later in the growing season.

This also holds true for lilacs that bloom twice a year, like Bloomerang Purple. After the bush’s initial bloom, you can prune it to promote new growth and more flowers in the second bloom, which occurs in early fall.

Lilacs eventually only bloom at the tips of their highest branches if allowed to develop naturally. Lilac bushes can be revitalized and made more visually appealing by pruning to maintain a balance between older stems and young blossoming branches.

Pruning a lilac shrub involves a number of techniques:

  • First, remove any weaker branches and any dead, broken, or diseased stems. Branches should also be trimmed to avoid rubbing or crossing.
  • Old stems that are thicker than two inches should be cut off. This controls the height of your lilac plant and promotes the development of new shoots. It is best to thoroughly remove the stems.
  • Control sucker emergence. Suckers are fresh branches that sprout from the plant’s base. The main branches can be replaced by a few robust suckers, but any lesser suckers should be removed at the soil line to prevent them from robbing the plant of nutrients.

Last but not least, here are some general guidelines for pruning lilacs:

  • Lilac bushes that are mature should only be pruned to a height of 6 to 8 feet.
  • Aim for 10 to 12 primary stems, each of which should be between 1 and 2 inches thick.
  • Never remove more than one-third of the bush with pruning.
  • Older stems and fresh blossoming shoots should be balanced.