It’s pretty rare to pass a garden and not spot some lilacs. They’re beautiful, low-maintenance, sweet-scented shrubs, so it’s easy to see why so many people grow lilacs.
The petals appear in clusters (or panicles) in the early spring and summer and they smell downright heavenly. For the rest of the year, the medium-to-large-sized leaves add cheery texture to the garden.
Whether you want to add a bush to your yard or just want to make an existing one happy, here’s what to know about growing lilacs.
What Are Lilacs?
Did you know that lilacs are part of the olive family? Obviously, the distinctive feature of these shrubs is their flowers, and they don’t produce edible fruit like their olive cousin. However, the flowers are edible.
In general, the blossoms are fragrant and come in pink, purple, and white. You can expect to see the petals in early spring through summer.
The most common species of lilac is Syringa vulgaris, which originates from East Asia and Southeast Europe. However, there are also other species and hybrids of this shrub that you can grow in your yard, such as:
- Persian lilac (S. x persica)
- Dwarf Korean lilac (S. meyeri)
- Japanese tree lilac (S. reticulata)
- Chinese lilac (S. x chinensis)
- Himalayan lilac (S. emodi)
The common, Chinese, Japanese tree, dwarf Korean, and lilac species generally grow well in USDA Growing Zones 3-8. They require freezing temperatures during the dormant season in order to produce those fragrant flowers in the spring, so Zones 9 and up are usually out (don’t worry, you have a few options).
Himalayan needs even colder weather and might struggle in Zone 8 and above.
Best Hybrids and Cultivars of Lilacs
There are many options out there when you’re lilac shopping. It never hurts to visit a local nursery and ask about what they have in stock, since they know what grows best in your garden. Here are some stand-outs:
This vulgaris cultivar has large, dark purple blossoms on long stems that make it perfect for cutting. In fact, it has the largest florets of any lilacs in this species. Grow this lilac in Zones 3-8.
S. vulgaris ‘Charles Joly’ has vibrant magenta flowers that feature double blossoms that last for nearly a month in Zones 3-7.
There’s nothing common about this beauty (S. vulgaris var. alba). The snowy white blossoms are extremely fragrant and this lilac can survive even in Zone 2.
This beautiful Japanese tree lilac grows up to 25 feet tall with massive cream-colored flowers that smell fantastic. Hardy in Zones 3-7.
This beauty features deep, dark purple-red flowers that are extremely fragrant. It starts blooming later in the season than many other varieties and grows in Zones 3-8.
‘Miss Kim’ (S. pubescens var. patula ‘Miss Kim’) is better for those in warmer regions, as she grows well in Zones 4-9. This is a dwarf shrub, topping out at about five feet.
If you thought you were out of the lilac game because you live in Zones 9 or 10, don’t worry. ‘Rosie’ is a vulgaris cultivar that can handle the heat. This plant has vibrant rose-pink blossoms that stand out.
Scentara Double Blue
‘Scentara Double Blue’ (S. x hyacinthiflora) has lilac-blue, double flowers that have a lovely scent on an eight-foot-tall shrub. Grow in Zones 2-8.
How to Plant Lilacs
The planting stage can either make or break the future of your shrub so you want to ensure that you do it right.
Plant lilacs in spring after the last projected frost day or in the fall a few weeks before the first projected frost date. Dig a hole in the soil that is twice as wide and slightly deeper than the container the plant comes in.
It’s a good idea to clean the roots slightly before placing the root ball into the soil. All you have to do is gently shake the roots to clear off any excess soil and to give the roots some room to spread.
The hole should be big enough to place the loosened root ball and still have some extra room for the roots to expand. If you want to grow several lilacs in one garden, leave 5 to 15 feet between them (depending on the variety) to avoid overcrowding.
After you’ve successfully placed the root ball into the ground you can water it thoroughly and leave it to grow. You’ll need patience when growing lilacs as they can take four or five years to show flowers. But, it will be entirely worth it when you have a garden full of fragrant blossoms!
Best Lilac Growing Conditions
The first thing to note about lilacs is they love sunlight.
Ideally, you want to pick a spot that will get sunlight for at least six hours a day. This is particularly important if you want the flowers to bloom well in your garden. Even though they thrive in full sun, they can handle some shade throughout the day as well.
Next on the list of growing requirements is soil. Lilacs need well-draining soil to be able to grow properly. You want a product that is rich, well-draining and has a neutral soil pH.
If you don’t naturally have well-draining, rich soil, fake it by working in lots of well-rotted compost into your existing soil.
As already mentioned, lilacs need cold winters. Although, they also enjoy warm summers. In areas that have hot weather and reach scorching temperatures, give them a little shade in the hottest part of the day.
If you live somewhere with high humidity, it can impact the growth of your shrub because excessive humidity can lead to fungal diseases.
Planting in Pots
There’s also the option of planting lilacs in pots or containers. You need a pot with at least a 24-inch width. This is a great alternative for people who don’t have a large garden but still want to benefit enjoy this lovely shrub.
Choose a dwarf variety such as ‘Minuet,’ ‘Pixie,’ or ‘Munchkin.’
Caring for Lilacs
These plants like a moderate amount of moisture, so you won’t need to water them constantly for them to grow. It’s especially important to avoid drowning your shrubs.
If lilacs are given too much water they could get root rot or fail to bloom. Allow the top two inches of soil to dry out between watering.
Another important element to caring for lilacs is fertilizer. You can feed your shrubs some fertilizer during spring, when they can benefit from some extra nutrients. Don’t use a product that is high in nitrogen as it may reduce the size and number of blossoms.
Instead, opt for a balanced fertilizer like this one from Amazon. Follow the manufacturer’s directions for application.
As well as watering your lilacs and giving them fertilizer, you should also schedule time for pruning the shrubs. Pruning will promote flower growth and encourage better air circulation to your plants.
You can start pruning lilacs after the flowers have bloomed. Remove all the spent blossoms and reduce the length of any leggy branches. Trim away any crossing branches or ones that show damage or disease.
If you have the space and don’t mind the overgrown look, then you can let them grow wild, but you might have fewer blossoms than you would on a maintained shrub.
Common Lilac Pests and Diseases
The majority of lilacs are resistant to many pests and diseases, but there are a few common problems to watch for.
There are several types of blight that attack lilacs: bacterial, shoot, and Asocochyta. These blights are caused by Pseudomonas syringae, Phytophthora cactorum, and Ascochyta syringae.
All blights cause the leaves or stems to shrivel and turn black or brown. The flowers might also be impacted.
Prune away any infected parts as soon as you see them. You should also try to maintain good spacing and avoid watering from overhead.
Powdery mildew can be found on lilac shrubs during summer when there is more humidity and dry weather.
You can notice this disease from its white, powdery texture that can be seen on the foliage of your plant. Thankfully, you can cure powdery mildew with a natural fungicide. So, if you run into trouble and this disease infects your shrubs, a treatment of fungicide should help!
Oystershell scale (Lepidosaphes ulmi) and apricot scale, or European fruit lecanium (Parthenolecanium corni), both feed on lilacs. Head to our guide to learn how to handle these pests.
Lilac borers (Podosesia syringae) are the larvae of wasp-like clearwing moths. The cream worms have brown heads and they bore into the stems of the plants. The stems will be weakened and the leaves will wilt.
You’ll need to prune out any infested stems since insecticides don’t usually work. In the fall, use a systemic pesticide such as the one made by Bonide in order to kill next year’s generation.
Obviously, you can just leave the flowers on your shrubs for a beautiful and fragrant spring display, but you can also cut the flowers and use them in vases to bring some of the magic indoors.
Lilacs are also edible. Try them candied, ground with sugar, or place the flowers in equal parts water and sugar, cover with cloth, and agitate daily. After a few days, strain out the petals and seal with a lid. In a few days, you’ll have a fizzy lilac cordial.