Lilacs: Plant and Flower Varieties, How To Grow and Plant Care

The lilac plant, also known as Syringa vulgaris, grows as a large shrub or tree, and this member of the olive family produces fantastically fragrant purple or white flowers.

The perfume of lilac is unmistakable, striking that delicate balance between being strong but not overwhelming, able to linger and travel. 

The blooms themselves brighten anywhere you choose to put them, and the branches provide architectural interest and height into any garden.

Interested in growing your own lilac? Here’s everything you need to know.

At a Glance: What You Should Know About Lilacs

The lilac plant comes from the Oleaceae plant family, as part of the Syringa genus. There are 12 species currently recognized within the genus, and within these species, hundreds of cultivars to select from.

The common lilac, Syringa vulgaris, is native to rocky hills of the Balkan Peninsula, and can be found in many parts of the world where the plant has naturalized. 

Other types hail from India, Nepal, China, Japan, Korea, Romania, among others. 

These plants are very long-lived, able to survive for hundreds of years with very little care, if any at all. They can also tolerate temperatures as low as 5°F (or -15°C).

The name of the genus originates from Ancient Greek, meaning tube or pipe, referencing the completely hollow branches of the common form of lilac. 

How to Recognize Lilac

Lilacs are classed as small trees. They can vary in height once the plant is mature, anywhere from a good standing at 6 feet tall, up to a very impressive 32 feet tall!

The stems are woody, bearing vibrant green leaves, which drop in the winter months. The foliage forms in clusters of three on opposite sides of the stem, and most are heart-shaped, but they can also be pinnate, or feather-like.

The plant really comes into its own during spring and summer, when it explodes into color with many flowers. 

The flower heads are made up of minute blooms which can measure between 5 and 10 mm each. Typically, a single flower will have four petals each, but in the more modern cultivars, it can be as many as ten or more.

You’ll usually find these heavily-scented flowers in shades of purple, but they can also come in pink, ivory, white, or burgundy.

The scent is dictated by the variety, some featuring very strong perfume, while others are completely unscented.

Unlike bulbs, lilac trees will flower year after year with the same amount of flowers or more, with no sign of stopping as long as you give them the right care. 

Some bulbs such as dahlias (see also Dahlia Care Guide) need to be rejuvenated by taking fresh cuttings, as they don’t all last for years, but with a lilac, it’s a much more reliable bloomer.

How to Grow Lilacs

You don’t need to be an expert gardener in order to grow lilacs in your own green space, in fact, they are one of the easiest trees you can grow yourself. 

However, there are a few things that you need to be aware of in order to get the best out of a lilac, and to ensure it survives for years to come, filling your garden with a wealth of color and fragrance. 

Sunlight and Position

The number one thing you must get right is the lilac’s position in your garden. 

Lilac plants love as much sunlight as possible, for as long as you can give them, so make sure you choose somewhere bright.

If possible, make it a sheltered area which gets plenty of airflow, and this will help keep the blooms on the tree for as long as possible, out of reach of the wind. 

Lilac trees require soil which drains well. Alkaline or neutral soil is best. If you have a garden which is full of chalky soil, this is perfect.

If you’re not sure what kind of soil you have, take a look at the plants already growing in your garden. 

This is a great way to tell, as some plants will only grow in certain soil types. Acidic soil lovers include magnolias, Japanese anemones, and Trillium, while alkaline soil lovers include lavender, honeysuckle, marjoram, and lily of the valley.

If you’re still unsure, you can buy a pH soil testing kit which will tell you. Bear in mind that different parts of your garden may have varying pH levels.

Preferably, it needs to be good-quality earth, full of nutrients, but you can also add nutrients with mulch or fertilizer, so don’t worry if this isn’t the case.

When to Water Lilac Trees

Lilac trees rarely need you to water them, unless you have recently planted one, and you’re trying to get the roots to establish, or there’s been a prolonged dry spell.

The roots of a lilac tree can reach more than a meter below the surface of the soil, so they do take care of themselves. 

One of the worst things you can do to a lilac is to overwater it, so always err on the side of underwatering this plant.

How to Plant Lilacs

The hardest part of keeping a lilac is planting it in the first place. You’ll need a good shovel for this! Make sure to choose somewhere sunny and sheltered to begin with.

It’s worth noting that planting lilac at different times of the year can make it much easier, or much harder to care for while it gets itself established.

Planting lilacs in spring or autumn is the best, as there are less dry spells, meaning that you won’t need to water it as often to encourage the roots to establish. The warmer weather of these two seasons helps, too.

For planting lilac into the ground, dig a hole that’s a little wider than the root ball, and make it just as deep. You want to plant the lilac as deep as its original pot. 

Once the hole is big enough, place the lilac tree in there, filling it with soil to the same level as it was before. 

Firm it in gently, which you can do by gingerly walking across the soil. This will help remove any air pockets within the soil, making sure that the roots have good contact with the earth, allowing for better drainage.

Water the plant to help settle in the roots. You’ll need to keep an eye on the plant, watering it in particularly hot weather until the roots have developed enough to let the plant fend for itself.

If you’d rather grow lilac in a container, you can do this too. Make sure that the pot is at least 60cm across, otherwise it is too small, and your lilac will outgrow it very quickly. 

Use a compost specially formulated for potted shrubs and trees, as it will help keep the roots weighed down, giving the plant the stability it needs. 

Mix in some horticultural grit or sand to help stop water pooling at the roots.

Deadheading and Pruning Lilacs

Lilacs do need some maintenance in order to keep the plants healthy, while also regulating the plant’s growth and keeping it balanced.

Regularly cut off any dead flower heads or fading blooms. You can also use lilac as the perfect cut flower to bring some fragrance and color indoors. 

Taking off some flowers will help the lilac tree to produce more, and it will also improve the air circulation around the plant, which helps prevent disease from taking hold.

Once the lilac has finished flowering, cut any diseased, dying or dead branches, pruning it back to a neat shape.

If the plant has gotten a little too wild to the point where it’s crying out for a drastic haircut, wait until the winter, when the temperature sends the plant into dormancy.

In winter, you can cut it back much harder than you would just after it has finished flowering. Not all flowering trees will respond well to hard pruning, but lilac is definitely one of them. 

If you want to create a brand-new shape for the tree, you can cut it back until the growth reaches 3 feet high and start again. 

There is a trade-off, however. Bearing in mind that lilac flowers on last year’s wood, if you prune it back hard, it won’t flower for a year or so. 

One way of getting around this is to gradually remove these unwanted branches, over a course of a few years, meaning that you’ll still get flowers on the branches you haven’t cut back.

Can You Propagate Lilac Trees?

Lilac trees can be propagated in two ways. You can either propagate them from suckers, which appear at the base of the plant, or take softwood cuttings.

Propagating a lilac tree by suckers is quicker and easier. All you need to do is to let the sucker grow big enough, and dig it up, making sure that you keep the roots intact, and put it elsewhere.

If you don’t have any suckers forming at the base of your lilac tree, or you don’t fancy digging around the lilac roots, you can take softwood cuttings instead.

The best time to take cuttings from lilac is during spring or summer. Only take from the plant what it has grown in its current season, as they will grow a lot quicker.

Using a sharp pair of secateurs, take a softwood cutting that is about 10cm in length, just above a leaf. 

Remove the lower leaves. On the remaining foliage, you can cut these in half to stop the cutting from losing water.

Dip the bottom of the cutting in hormone rooting powder. This isn’t a required step, but it helps, encouraging the cutting to grow roots faster.

Grab a container and fill it with damp compost. Put the cuttings into the soil, the foliage just above the soil line, around the edges of the pot.

To help keep the humidity levels up and to avoid any water loss, you can cover the pot with a clear plastic bag, securing it tightly. Put the pot somewhere warm but away from direct sunlight.

Once you notice new growth on the cuttings, they will have formed roots, at which point it’s time to put them in individual pots.

Problems to Look Out for When Growing Lilacs

Lilac trees are robust plants, but that doesn’t mean that they are completely immune to problems. 

Fewer Flowers

If you notice that your lilac tree isn’t producing as many flowers as it should during spring, this could be due to late frosts, or another issue. Poor light levels will result in few flowers, as will soil that doesn’t drain enough.

Moths

The lilac tree is a magnet for some types of moth, as they are a food source for the larvae. Lilac borers are a particular type of moth which can damage not only lilac trees, but ash trees as well.

They tend to focus their efforts on the main trunk of a lilac tree and branches which are mature, digging ‘galleries’ into the tree, and feeding on the sapwood.

The only real way to get rid of lilac borers is to prevent them in the first place. Try to keep your lilac trees as healthy as possible, providing them with the right growing conditions, making sure to water them in dry spells.

If you accidentally cut the trunk of the tree, this can attract lilac borers. Once they are in the tree, they are very difficult to get rid of, as contact insecticides don’t work, as they cannot reach.

You can use pheromone traps, laying them in spring. This will catch the male moth, reducing the numbers of lilac borers around. 

To help stop existing moths, use an insecticide spray on the trunk and branches, when the lilac flowers are fading. Make sure to wear appropriate protective clothing, and don’t do this in the day, otherwise you could end up harming other insects such as bees.

Lilac Blight

You’ll notice lilac blight when the foliage starts to discolor, becoming misshapen, and dropping from the plant well before it should. It also attacks the flowers, rendering them brown and withered.

The best way to deal with lilac blight is to cut back the diseased parts of the plant. Sterilize your shears, and prune some healthy parts of the plant, too. 

Make sure to dispose of any diseased plant parts properly, not adding them to compost where the disease may spread.

Powdery Mildew

If you don’t give your lilac enough space, either by not pruning it for a few years, or planting it too close to neighboring plants, the air circulation around your plant will become a lot lower than it should be. 

Poor air circulation causes fungal disease, and one of the most common ones is powdery mildew. It looks exactly how it sounds, settling a powdery substance onto the foliage and flowers.

It can make young leaves crinkle, cup, or otherwise distort. The best conditions for powdery mildew to form are warm temperatures and humidity. If left unchecked, it can spread across the plant to neighboring plants, too.

Noticing it and treating it early will go a long way to help your plant. Leaving it for an extended period of time can really weaken your lilac plant, so the sooner you treat it, the better off your plant will be.

To help get rid of powdery mildew, prune back the lilac bush or tree every year once it has finished flowering. You don’t have to cut back a huge amount. In fact, it’s better if you don’t, as the flowers formed on last year’s wood.

Just cut back enough to make sure that there’s a good amount of airflow around the lilac and other plants, and this will go a long way in preventing powdery mildew.

It may be worth cutting back the neighboring plants too, to further improve the air circulation.

When you cut back foliage – no matter the season – don’t let the debris just sit on the soil. This can encourage disease of all kinds. The one exception to this is using rhododendron leaves underneath a rhododendron to improve the pH.

Always clear the surface of the soil of any dead leaves or weeds, too. Powdery mildew and other diseases can survive on dead plant matter through winter, so clearing away any debris will help keep it at bay.

If you do notice powdery mildew on your lilac, hold off on feeding the plant. While feeding a plant when it’s less than perfectly healthy sounds like a good idea, it’s not recommended. 

You can do more harm than good, as powdery mildew settles well on vulnerable, new shoots, finding it difficult to settle on much older growth. 

Feeding the plant encourages the plant to put out new growth, so waiting until you’ve got rid of the fungus will help the plant cope. 

Reducing the amount of times you feed the plant will also slow down its growth rate, stopping it from overcrowding the area, and preventing powdery mildew.

Honey Fungus

One thing to keep an eye out for is honey fungus, as it can cause a lot of damage to your whole garden. 

In some parts of the world where these fungi are native, numbers are usually kept down by other types of fungi, but in gardens, these competing types are rarely present, allowing the honey fungus to get a foothold.

Honey fungus moves underground, attacking the roots of perennials and trees. It can be difficult to spot, as it doesn’t always produce the honey-colored mushrooms it is known for.

Signs of a honey fungus infection include pale leaves or leaves dying well before they should, no flowers during the right season, cracked or bleeding bark, and plant death.

A few of these symptoms can also be caused by improper growing conditions, so to make sure it is honey fungus, crouch to the base of a lilac trunk. 

Remove some of the bark. If it is honey fungus, you’ll notice white mycelium, which are white filaments of the fungus, growing between the wood and the bark.

There’s no real way to eradicate the fungus besides pulling up the plant and its roots, and disposing of it carefully. Instead, what you’ll need to do is to manage it.

Controlling the fungus is the easier method. You can do this by keeping your plants as healthy as possible, making sure that they aren’t stressed by the wrong conditions.

Get rid of a layer of soil at the bottom of plant stems. Remove as much of the affected plant as possible, and any plants growing around it. You can dig the soil to get rid of infected roots or parts of the fungus. 

Don’t plant anything new into the affected area for about a year, and this will help starve the fungus.

How to Make the Most of Lilac Trees

Lilac trees can act as a real focal point in your garden, no matter what size of lilac you go for, whether that’s as a bush or a large tree.

Before they even flower, they inject a lot of height and structure into your garden, whether you go for a standard variety, or a dwarf cultivar. 

This draws your gaze to different levels of the garden, making it look much bigger and adding more interest.

Lilacs add plenty of color into any sunny position in your garden, whether you go for a bicolored variety, or one solid color. 

These blooms attract many pollinators, filling your garden with activity and boosting the overall health of your green space and the plants within.

Position Your Lilac Well

It’s worth planning ahead if you want to introduce lilacs to your garden, as it grows quickly, and needs a lot of room, but some require less space than others.

Some standard varieties can reach up to 32 feet tall, and some are smaller at 6 feet, and it largely depends on how much you will prune them as to how much space they’ll need.

If space is at a premium in your garden, you can introduce a dwarf lilac variety in a large container, making sure to prune it back once it has finished flowering, and this will stop it taking over the space you have.

One of the best ways to make the most out of a lilac is to plant the bush or tree somewhere near the windows and doors of your home, or near a seating area or patio. 

Not only will the flowers be a great sight from inside, but you’ll be able to make the most of the fragrance, too.

Companion Planting

It’s also worth doing some companion planting to really bring the best out of these hardy plants. 

While beautiful, lilacs can need a mixed planting scheme to really bring them out, as the flowering period is fairly short. 

You can extend it by growing several lilac varieties that flower at different times, if you want more of the same.

They also work well with different forms and colors during the flowering season. One of the easiest ways to do this is to use spring bulbs, and depending on the variety of your lilac, the bulbs might come out first, providing a lot of color when the lilac is still bare.

There are plenty to choose from, such as daffodils, tulips, crocuses, phlox, and columbine. The different structures and color found in these plants will offset the form and vivid color found in the lilacs, bringing the best out of both.

Lilac Varieties to Grow in Your Own Garden

There are countless varieties to pick from when it comes to growing lilac in your own garden. Here are just a few of the most fantastic varieties available, to help get you started.

Syringa hybrida ‘Bloomerang Penda’

A hybrid lilac, this is the perfect variety for a smaller garden without compromising on flowers. 

In fact, you could say that it maximizes on flowers. It produces a wealth of flowers in two separate flushes, unlike the traditional lilac, which produces one in spring. 

In late spring, ‘Penda’ is just one variety of a series that bursts into color during the later weeks of spring, and then again in the height of summer, where the second flush will last until the first frosts hit.

The flowers themselves form in almost globular clusters, ‘Penda’ putting on an exclusively purple display, contrasting well with the vibrant green leaves.

‘Penda’ can reach a maximum height of six feet tall once it has matured, though if you keep pruning it, it may be a more suitable 3 feet high for smaller gardens.

Syringa meyeri ‘Palibin’

‘Palibin’ is a dwarf Korean lilac variety, able to reach 4 feet tall, making it a better choice if you want to grow lilacs in a container or a smaller garden. It also helps that it takes its time to get there, being a slow-growing cultivar.

This cultivar boasts a sea of color in late spring until the first few weeks of summer, in purple and pink, and the oval leaves make a nice contrast in deep green. The flowers are hugely scented, only adding to the plant’s beauty. 

Syringa reticulata ‘Ivory Silk’

A Japanese tree lilac (see also Flower Names Starting With J), ‘Ivory Silk’ is perfect if you have a large garden, and you need a plant that will really make a statement. 

With time, it is capable of reaching 25 feet tall, and 15 feet wide, so you will need plenty of room for this one!

It’s perfect for introducing some shade into a very sunny part of your garden, while also providing a wealth of creamy-white flowers in that instantly-recognizable, lilac perfume.

During the autumn and winter months, this plant has another treat for you. Once the foliage drops off, it adds color and interest with its deep red bark.

Syringa vulgaris ‘Charles Joly’

If you prefer your lilac flowers in much deeper shades, Syringa vulgaris ‘Charles Joly’ is the one to go for. 

It reaches a maximum height of 12 feet, spreading up to 10 feet wide. It really comes into its own from mid-spring onward, where it will inject your garden with double-flowering, deep purple blooms for about a month.

It also won the AGM award from the Royal Horticultural Society.

Syringa vulgaris ‘Firmament’

For blooms in cooler tones, ‘Firmament’ is a great choice. During the last few weeks of spring, this cultivar produces tightly-packed panicles of pastel blue-purple flowers.

You’ll be hard-pressed to find a variety of lilac which is so abundant in fragrance as ‘Firmament’, as what these flowers lack in longevity, they make up for in their perfume.

‘Firmament’ can reach up to 13 feet tall, making it perfect for screening in the spring and summer months with its packed foliage and vigorous growth. 

Syringa vulgaris ‘Madame Lemoine’

‘Madame Lemoine’ is a great option for white-flowering lilacs. 

From mid-spring into the first few weeks of summer, ‘Madame Lemoine’ puts on a fantastic display of fragrant, pure-white double flowers, attracting a huge amount of butterflies and other pollinators into your garden.

The foliage is heart-shaped in a medium green, adding another level of interest in this attractive plant. It will reach a maximum height of 13 feet once it matures, and it prefers moist soil which drains well.

Syringa vulgaris ‘Primrose’

For a smaller variety bearing white flowers, ‘Primrose’ might be the one for you. It will reach a maximum height of 8 feet once the plant has matured, making it perfect for container gardens, or ones which don’t have a huge amount of room.

‘Primrose’ flowers from mid-spring into early summer, producing beautiful white blooms which take on an ivory, creamy tinge once they mature, providing your garden with a wealth of scent, too. 

They make the perfect cut flower for spring arrangements, but they are also popular with butterflies and bees.

Syringa vulgaris ‘Sensation’

If traditional lilac flowers aren’t really your thing, and you want a very unusual variety, ‘Sensation’ may be the one for your garden.

This particular cultivar produces purple flowers with a reddish tinge, each one beveled in white, highlighting the lovely shape of each individual flower.

These blooms go well against the deep green, heart-shaped foliage. Eventually, ‘Sensation’ will reach 13 feet tall, and it will spread about the same.

Syringa vulgaris ‘Tiny Dancer’

No matter if you’re an Elton John fan, or you’re just looking for a variety that will not take over your garden if you don’t cut it back constantly, ‘Tiny Dancer’ may be the one for you.

More dwarf than most, ‘Tiny Dancer’ reaches a maximum height of 5 feet, boasting striking light purple flowers which have a very heady perfume.

There is a drawback to this lovely variety, however. It won’t withstand as much cold as other varieties, but it does have a better resistance against fungal infection, making it perfect for areas that get a lot of rainfall.

Syringa x Bailbelle ‘Tinkerbelle’

If you’re really short on space, but you’d still like to grow lilacs in your own garden, Syringa x Bailbelle ‘Tinkerbelle’ may be the variety you should go for. 

It can grow anywhere from 4 to 6 feet high, depending on how often you prune it, and it will tolerate a somewhat-shady position if full sunlight isn’t available. 

‘Tinkerbelle’ produces deep red flower buds, which open out into soft pink perfumed flowers, and these gorgeous flowers last for about a month. 

‘Tinkerbelle’ is also a great option if you live somewhere that gets a lot of dry spells, and high temperatures. It’s a drought tolerant plant, but it does need good airflow around the plant to stop disease.

Syringa x chinensis ‘Saugeana’

Also known as ‘Persian’, this lilac is the resulting hybrid of Syringa vulgaris and Syringa persica, and it’s often called the Rouen lilac, as it was discovered in Rouen in France, in 1777

This particular variety has a lovely sweet scent, producing blooms in pastel purple from mid-spring into the early summer. 

You can grow it in a pot if you prefer, as it can reach about 4 feet tall if you keep it trimmed. Alternatively, you can grow it to 8 feet tall when you plant it into the ground. 

It will grow in nearly any soil type, and it’s also fairly hardy.

Syringa x hyacinthiflora ‘Maiden’s Blush’

A hyacinth lilac is a cross between Syringa oblata, the early-flowering lilac, and Syringa vulgaris, the common lilac. 

As a result, these hybrids flower at least a week earlier than the common lilac, making them perfect for early color in spring. 

The foliage can also turn red, purple, or gold in the autumn months, making these hybrids a very attractive option when you’re considering what to go for. 

Eventually, ‘Maiden’s Blush’ will reach anywhere between 10 and 12 feet high and wide once it matures, making it a decent choice for mixed beds or for the middle of borders.

This is a fairly ‘new’ hybrid, having been introduced in 1966. The plant really comes into its own as the flowers appear, the clusters being bicolored, with dark purple buds opening into baby pink flowers.

These blooms offset the vibrant green leaves nicely, and will make a good focal point in any garden.

Syringa x hyacinthiflora ‘Scentara Double Blue’

‘Scentara Double Blue’ has a lot to offer. This lilac produces double-flowers in a rich blue-purple from mid-spring onward, filling your garden with color and scent. They also make for an excellent cut flower.

While it is a hyacinth lilac, it still features the classic perfume of a common lilac that so many people adore. 

This particular lilac will grow anywhere from 6 to 8 feet tall, making it a good choice for gardens which don’t have a lot of space.

Syringa x vulgaris ‘Ludwig Spaeth’

For a much deeper color, ‘Ludwig Spaeth’ is among the most richly pigmented hybrid lilacs available. 

It explodes into color slightly later than most lilacs, in either late spring or early summer, boasting dark purple flowers with a rich red tone. 

It can reach a maximum of 10 feet tall once the plant gets to maturity, but it can also spread to 8 feet wide, making it a good option for a fragrant hedge.

Syringa ‘Red Pixie’

Reaching just under 6 feet tall, Syringa ‘Red Pixie’ is a more compact form of lilac, perfect for smaller beds or large pots. 

It’s unusual in that it flowers more than once. The sea of pink panicles appears during spring, and then again in the later weeks of summer, or the start of fall.

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