Common Lilac (Syringa vulgaris)

Common lilac, also known by other names like Syringa vulgaris, and French lilac, is a beloved deciduous shrub cherished for its fragrant spring blooms and relatively easy care. This guide, brought to you by Gardencenterpoint.com, will cover everything from planting and pruning to troubleshooting common diseases.

We will explain selecting the best common lilac varieties, providing step by step instructions to care for common lilac and solutions if you encounter any common lilac diseases. Continue reading to discover all the helpful content.

What is Common Lilac?

The common lilac (Syringa vulgaris) is a member of the olive family (Oleaceae). It’s native to the Balkan Peninsula in Southeastern Europe, but it has been naturalized across much of Europe and North America. The plant’s popularity stems from its iconic clusters of flowers, known as panicles, which release a powerful, sweet fragrance. These flowers typically bloom in mid-spring, though the exact timing can vary depending on the climate and cultivar.

Common Name(s)	Common Lilac, French Lilac, Lilac
Botanical Name	Syringa vulgaris
Family	Oleaceae (Olive family)
Genus	Syringa
Species	vulgaris
Origin	Balkan Peninsula (Southeastern Europe)
Native Area Southeastern Europe
Life Cycle	Perennial (lives for more than two years)
Plant Type	Deciduous shrub (or small tree)
Hardiness Zones	3-7 (tolerates cold winters)
Sunlight	Full Sun (at least 6 hours of direct sunlight per day)
Maintenance	Low to Moderate
Water Needs	Moderate (drought-tolerant once established, but benefits from regular watering during dry periods)
Soil Drainage	Well-Drained (essential; does not tolerate soggy soil)
Soil pH	Slightly Alkaline to Neutral (6.5 to 7.0 ideal)
Spacing	8-15 feet apart (depending on variety and desired growth habit)
Flowering Period	Mid-Spring (typically, though some varieties bloom earlier or later)
Height	12-16 feet (typical, but can vary by variety; some dwarf cultivars exist)
Width 8-12 feet (typical, can vary)
Growth Rate	Moderate
Flower Color	Wide range
Flower Form	Single or Double (depending on variety)
Flower Benefit	Intense Fragrance, Attracts Pollinators, Beautiful Cut Flowers
Foliage Color	Medium to Dark Green
Stem Color	Gray to Brown
Garden Style	Cottage, Traditional, Informal, Pollinator Garden
Uses	Specimen Plant, Hedge, Border, Cut Flowers, Fragrance Garden, Wildlife Garden, Erosion Control (in some cases)
Disease/Pest Note	Can be susceptible to Powdery Mildew, Lilac Borer, and other issues (see Troubleshooting section for details)
Propagation Methods	Softwood Cuttings, Hardwood Cuttings, Layering, Grafting, Division

Key Characteristics:

• Growth Habit: A multi-stemmed, deciduous shrub or small tree.
• Size: Typically grows 12-16 feet tall and 8-12 feet wide, though some varieties can be larger or smaller.
• Foliage: Simple, opposite leaves that are typically heart-shaped or oval. The leaves are usually medium to dark green.
• Flowers: The most recognizable feature. Panicles are composed of numerous small, four-petaled flowers. Colors range from the classic lilac purple to white, pink, magenta, and even bi-colors.
• Fragrance: Intensely fragrant, with a sweet, floral scent.
• Hardiness: Generally hardy in USDA zones 3-7, meaning they can tolerate cold winters.
• Sunlight Common lilacs prefer to be in full sun.

Historical Significance and Cultural Impact:

Lilacs have a rich history and have been cultivated for centuries. They were brought to North America by European colonists in the 17th century and quickly became a popular garden plant. They are often associated with spring, nostalgia, and romance. Lilacs are frequently featured in poetry, literature, and art.

A study from the University of Vermont Extension confirms the popularity of lilacs, stating that they are among the most frequently planted flowering shrubs in colder climates. This is due to their hardiness, beauty, and fragrance. (Source: University of Vermont Extension, Department of Plant and Soil Science: https://www.uvm.edu/extension)

The enduring appeal of the common lilac lies in its combination of visual beauty, delightful fragrance, and relatively low maintenance. It’s a plant that brings a touch of classic elegance to any garden. The wide range of cultivars available also means that there’s likely a common lilac to suit almost any garden style and preference.

How to Care for Common Lilac

Proper care is essential for ensuring your common lilac thrives and produces abundant, fragrant blooms. This section provides a detailed guide to all aspects of common lilac care.

Planting Your Common Lilac

• Timing: The best time to plant a common lilac is in the fall, after the leaves have dropped but before the ground freezes. Spring planting is also possible, but you’ll need to water more diligently during the first summer.
• Location: Choose a site that receives at least six hours of direct sunlight per day. Lilacs need full sun to bloom well. They also prefer well-drained soil. Avoid planting in areas where water tends to pool after rain.
• Soil: Lilacs prefer slightly alkaline to neutral soil (pH 6.5 to 7.0). If your soil is acidic, you can amend it with lime to raise the pH. A soil test is always a good idea to determine the exact pH and nutrient levels.
  1. Soil Testing: You can purchase a soil testing kit from most garden centers or send a sample to a local cooperative extension office.
• Planting Procedure:
  1. Dig a hole that is twice as wide as the root ball and just as deep.
  2. Gently loosen any circling roots around the outside of the root ball.
  3. Place the plant in the hole, making sure the top of the root ball is level with the ground.
  4. Backfill the hole with soil, tamping it down gently to remove air pockets.
  5. Water thoroughly after planting.
• Spacing: Space common lilacs 8-15 feet apart, depending on the mature size of the variety you’ve chosen. Proper spacing allows for good air circulation, which helps prevent diseases.

Watering Your Common Lilac

• Newly Planted Lilacs: Water deeply and regularly during the first growing season, especially during dry spells. Aim to keep the soil consistently moist, but not soggy.
• Established Lilacs: Once established, common lilacs are relatively drought-tolerant. However, they will benefit from supplemental watering during prolonged dry periods, especially during the summer months.
• Watering Technique: Water deeply and infrequently, rather than shallowly and frequently. This encourages deep root growth, which makes the plant more resilient.
• Mulching: Apply a 2-3 inch layer of organic mulch, such as wood chips or shredded bark, around the base of the plant. Mulch helps conserve soil moisture, suppresses weeds, and regulates soil temperature. Keep the mulch a few inches away from the stems to prevent rot.

Fertilizing Your Common Lilac

• Timing: Fertilize common lilacs in early spring, before new growth begins.
• Type of Fertilizer: Use a balanced, slow-release fertilizer formulated for flowering shrubs. A 10-10-10 fertilizer is a good general choice. Alternatively, you can use a fertilizer specifically formulated for lilacs.
• Application Rate: Follow the instructions on the fertilizer package carefully. Over-fertilizing can damage the plant and reduce flowering.
• Avoid High-Nitrogen Fertilizers: Fertilizers with a high nitrogen content (the first number in the N-P-K ratio) can promote excessive leafy growth at the expense of flowers.

Pruning Your Common Lilac

• Timing: The best time to prune common lilacs is immediately after they finish flowering in late spring. This allows the plant to set flower buds for the following year.
• Pruning Goals:
  • Remove any dead, damaged, or diseased wood.
  • Thin out crowded branches to improve air circulation and light penetration.
  • Remove suckers (shoots growing from the base of the plant) if you want to maintain a single-trunked or few-stemmed form.
  • Shape the plant to maintain its desired size and form.
• Pruning Techniques:
  • Use sharp, clean pruning shears or loppers.
  • Make cuts at a 45-degree angle, just above a bud or branch junction.
  • Remove up to one-third of the oldest stems each year to rejuvenate the plant.
  • Avoid shearing the plant into a formal hedge, as this will reduce flowering.
• Renewal Pruning: For very old, overgrown lilacs, you can perform a more drastic renewal pruning. This involves cutting the entire plant back to about 6-12 inches above the ground. This will rejuvenate the plant, but it will take a few years for it to flower fully again.

Protecting Your Common Lilac in Winter

• Hardiness Zones: Common lilacs are generally hardy in USDA zones 3-7.
• Protection in Colder Zones: In zones 3 and 4, it’s a good idea to provide some winter protection, especially for young plants. You can wrap the plant in burlap or apply a thick layer of mulch around the base.
• Snow Load: Heavy snow can damage branches. Gently brush off heavy snow accumulation to prevent breakage.

Common Lilac Diseases and Pests

While common lilacs are relatively hardy, they can be susceptible to certain diseases and pests. This section provides information on identifying and managing common problems.

Common Lilac Diseases

• Powdery Mildew: A fungal disease that appears as a white, powdery coating on the leaves, stems, and flowers. It’s most common in humid conditions with poor air circulation.
  • Prevention: Plant in full sun with good air circulation. Avoid overhead watering.
  • Treatment: Apply a fungicide labeled for powdery mildew. Several organic options are available, such as neem oil or sulfur.
• Bacterial Blight: A bacterial disease that causes brown spots on the leaves, which eventually spread and cause the leaves to wither and die. It can also cause cankers (sunken lesions) on the stems.
  • Prevention: Avoid overhead watering. Prune out infected branches promptly.
  • Treatment: There is no cure for bacterial blight. Prune out infected branches, cutting well below the affected area. Disinfect your pruning tools between cuts.
• Lilac Leaf Spot: Several fungal diseases can cause leaf spots on lilacs. These spots are usually brown or black and may have a yellow halo.
  • Prevention: Improve air circulation. Avoid overhead watering.
  • Treatment: Remove and destroy infected leaves. Apply a fungicide if the problem is severe.
• Verticillium Wilt: A soilborne fungal disease that can cause wilting, yellowing, and dieback of branches.
  • Prevention: Plant in well-drained soil. Avoid overwatering.
  • Treatment: There is no cure for Verticillium wilt. Remove and destroy affected plants.

Common Lilac Pests

• Lilac Borer: The larvae of a clearwing moth that bore into the stems of lilacs, causing wilting and dieback.
  • Prevention: Keep plants healthy and vigorous. Prune out infested branches.
  • Treatment: Apply an insecticide labeled for lilac borer in the spring, when the adults are active.
• Scales: Small, sap-sucking insects that appear as bumps on the stems and leaves.
  • Prevention: Keep plants healthy. Encourage natural predators, such as ladybugs.
  • Treatment: Apply horticultural oil or insecticidal soap.
• Leafminers: The larvae of small flies that tunnel inside the leaves, creating winding trails.
  • Prevention: Usually not a serious problem.
  • Treatment: Remove and destroy infested leaves.
• Aphids: If your common lilac have this pest. You can use insecticidal soap.

Important Note: Always read and follow the instructions on any pesticide or fungicide label carefully. When possible, choose organic or less-toxic options.

Common Lilac Varieties: A World of Color and Fragrance

Choosing the right common lilac (Syringa vulgaris) variety is a delightful task, given the sheer number of cultivars available. The selection process goes beyond just picking a color; it involves considering size, bloom time, fragrance intensity, and even disease resistance. Gardencenterpoint.com is here to help you navigate this fragrant world and select the perfect lilac for your garden.

The classic image of a lilac is a large shrub with abundant lavender-purple flowers. While this is certainly a beautiful option, the diversity within Syringa vulgaris is truly remarkable. You can find varieties with flowers in shades of white, pink, magenta, deep purple, and even bi-colors. Some have single flowers (four petals), while others have double flowers, creating a fuller, more lush appearance.

Understanding Flower Color and Form:

• Purple/Lavender: The most traditional and popular color. Varieties range from pale lilac to deep, rich purple. Examples include ‘Ludwig Spaeth’ (deep purple-red) and ‘Monge’ (deep purple).
• White: White lilacs offer a classic, elegant look. They can brighten up a shady corner of the garden. Consider ‘Madame Lemoine’ (double white) or ‘Mount Baker’ (single white).
• Pink: Pink lilacs range from soft, pastel pinks to vibrant magenta. ‘Belle de Nancy’ (double pink) and ‘Assessippi’ (light pink) are popular choices.
• Blue: While true blue is rare in lilacs, some varieties have a distinct bluish hue. ‘President Lincoln’ is considered one of the best “blue” lilacs.
• Bi-color: These varieties offer a unique and eye-catching display. ‘Sensation’ is a standout with its purple flowers edged in white.
• Double Flowers: Double-flowered varieties have extra petals, giving the flower clusters a fuller, more textured appearance. Many gardeners find them to be even more fragrant than single-flowered types.

Considering Size and Growth Habit:

Common lilacs are typically large shrubs, but there are also smaller, more compact varieties available. This is important to consider when choosing a location in your garden.

• Large Varieties (12-16 feet tall and wide): ‘Ludwig Spaeth’, ‘Monge’, ‘President Grevy’ (double lilac-blue). These are best suited for larger gardens or as specimen plants.
• Medium Varieties (8-12 feet tall and wide): ‘Charles Joly’ (double magenta), ‘Belle de Nancy’ (double pink), ‘President Lincoln’. These are versatile and can fit into many garden settings.
• Compact Varieties (4-8 feet tall and wide): These exist, it is important to note that these are usually not a Syringa vulgaris, commonly referred to as common lilac. Syringa meyeri ‘Palibin’ (dwarf Korean lilac, though not a Syringa vulgaris) is a good example.

Bloom Time and Fragrance:

Most common lilacs bloom in mid-spring, but there are some variations. If you want to extend the lilac season in your garden, you can choose varieties with slightly different bloom times.

• Early Bloomers: Syringa x hyacinthiflora varieties, such as ‘Pocahontas’ (deep purple), tend to bloom earlier than most common lilacs.
• Mid-Spring Bloomers: This is the peak bloom time for most common lilacs.
• Late Bloomers: Some varieties, such as Syringa vulgaris ‘Miss Kim’ (although Miss Kim is technically a Manchurian lilac, not a true common lilac), bloom slightly later than the majority. Miss Kim, is also more resistant to powdery mildew.

Fragrance is a key characteristic of lilacs, but the intensity can vary between varieties. Most are strongly fragrant, but some are more subtly scented. If fragrance is a top priority, research the specific variety before purchasing.

Disease Resistance:

Powdery mildew is a common fungal disease that can affect lilacs, especially in humid climates. Some varieties are more resistant to this disease than others. If powdery mildew is a concern in your area, look for resistant varieties.

Best Common Lilac Varieties

There are hundreds of common lilac cultivars available, offering a wide range of colors, sizes, and bloom times. This table provides a guide to some of the most popular and highly-rated varieties.

Variety	Flower Color	Size (H x W)	Fragrance	Bloom Time	Characteristics
‘Ludwig Spaeth’	Deep purple-red	10-12′ x 8-10′	Strong	Mid-spring	Classic, reliable variety with large, fragrant blooms.
‘President Lincoln’	Wedgewood blue	8-10′ x 6-8′	Strong	Mid-spring	One of the best blue-flowered lilacs.
‘Sensation’	Purple with white edge	10-12′ x 8-10′	Strong	Mid-spring	Unique bi-color flowers.
‘Charles Joly’	Double magenta	8-10′ x 6-8′	Strong	Mid-spring	Double flowers provide extra fullness and fragrance.
‘Belle de Nancy’	Double pink	8-10′ x 6-8′	Strong	Mid-spring	Another excellent double-flowered variety.
‘Monge’	Deep purple	10-12′ x 8-10′	Strong	Mid-spring	Large, intensely fragrant flowers.
‘Primrose’	Pale yellow	8-10′ x 6-8′	Moderate	Mid-spring	A unique yellow-flowered lilac. The color is more cream than true yellow.
‘Yankee Doodle’	Deep Purple	6-8′ x 5-7′	Strong	Mid Spring	Very Cold Hardy.
Syringa x hyacinthiflora ‘Pocahontas’	Deep Purple	10-12′ x 8-10′	Strong	Early Spring	Very fragrant, blooms earlier than most common lilacs.

Choosing the Right Variety:

• Flower Color: Consider your personal preference and the overall color scheme of your garden.
• Size: Choose a variety that will fit the available space in your garden.
• Bloom Time: If you want a long season of lilac blooms, choose varieties with different bloom times (early, mid, and late).
• Fragrance: While most common lilacs are fragrant, some are more intensely fragrant than others.
• Disease Resistance: Some varieties are more resistant to diseases like powdery mildew.

Where to Buy Common Lilacs

You can purchase common lilac plants from local garden centers, nurseries, and online retailers. Gardencenterpoint.com can help you find reputable sources for purchasing high-quality lilac plants. We provide connections to trusted nurseries and garden centers, ensuring you receive healthy, vigorous plants.

Propagation

Common lilacs can be propagated through several methods, including:

• Softwood Cuttings: Taken in late spring or early summer from new growth.
• Hardwood Cuttings: Taken in late fall or winter from dormant wood.
• Layering: Bending a low-growing branch to the ground and burying a portion of it to encourage root growth.
• Grafting: Joining a scion (a cutting from the desired variety) onto a rootstock (a different lilac plant). This is often used for propagating named cultivars.
• Division. Dividing a lilac is generally best done in early spring, before new growth starts, or in the fall, after the plant has gone dormant.

Uses and Benefits

Beyond its ornamental value, the common lilac offers several other uses and benefits:

• Cut Flowers: Lilac blooms make beautiful and fragrant cut flowers. Cut the stems when the flowers are about half-open. Remove any leaves that will be below the waterline in the vase.
• Essential Oil: Lilac essential oil is extracted from the flowers and used in perfumery, aromatherapy, and cosmetics. It is known for its calming and relaxing properties.
• Medicinal Uses (Historical): Historically, various parts of the lilac plant have been used in traditional medicine to treat a variety of ailments. However, it’s important to note that there is limited scientific evidence to support these uses, and lilac should not be used as a substitute for medical treatment. Consult a healthcare professional before using lilac for medicinal purposes.
• Wildlife Value: Lilac flowers attract pollinators, such as bees and butterflies. The dense foliage can also provide shelter for birds.
• Erosion Control: The extensive root system of lilacs can help stabilize soil and prevent erosion.

Common Lilac Problems

Even with the best care, you may occasionally encounter problems with your common lilac. This section addresses some common issues and provides solutions.

• Problem: No flowers or very few flowers.
  • Possible Causes:
    • Not enough sunlight (at least 6 hours of direct sun per day).
    • Improper pruning (pruning at the wrong time of year removes flower buds).
    • Over-fertilizing (too much nitrogen promotes leafy growth at the expense of flowers).
    • Young plant (it may take a few years for a newly planted lilac to start blooming profusely).
    • Poor soil conditions.
  • Solutions:
    • Ensure the plant is receiving enough sunlight.
    • Prune immediately after flowering in late spring.
    • Use a balanced fertilizer or a fertilizer specifically formulated for lilacs.
    • Be patient.
    • Amend the soil if necessary.
• Problem: Leaves are yellowing.
  • Possible Causes:
    • Overwatering or poor drainage.
    • Nutrient deficiency (especially iron deficiency).
    • Disease (such as Verticillium wilt).
  • Solutions:
    • Improve drainage or reduce watering.
    • Apply a fertilizer containing iron.
    • If a disease is suspected, consult a plant pathologist or your local cooperative extension office.
• Problem: Leaves have spots or holes.
  • Possible Causes:
    • Fungal diseases (such as leaf spot).
    • Pests (such as leafminers or Japanese beetles).
  • Solutions:
    • Remove and destroy infected leaves.
    • Apply a fungicide or insecticide if necessary.
• Problem: Stems are wilting or dying back.
  • Possible Causes:
    • Lilac borer.
    • Bacterial blight.
    • Verticillium wilt.
  • Solutions:
    • Prune out infested or diseased branches.
    • If lilac borer is suspected, apply an insecticide.
    • If Verticillium wilt is suspected, there is no cure. Remove and destroy affected plants.