Syringa vulgaris

Although Syringa vulgaris is native to southeastern Europe, it has been naturalized in many other regions of the globe.The plant has been used ethnobotanically to reduce fever and treat malaria, as a perfume and a tonic, and in homeopathy.

 
Photo Credit: © R.A. Howard. Courtesy of Smithsonian Institution, Dept. of Systematic Biology, Botany.
Syringa vulgaris
Common Name: common lilac
Plant Functional Group: Deciduous broadleaf
Class > Order > Family: Magnoliopsida > Lamiales > Oleaceae
What does the species look like?

Common lilac is an introduced, perennial, deciduous shrub that grows between 12 to 16 feet tall. The flowers are mostly white, lilac, or purple, and pleasantly fragrant in long terminal panicles.

Common lilacs (also called "hedge" or "old-fashioned") are often sold in nurseries or are found already growing on homesites. They have leaves that are somewhat heart-shaped and are much wider than the leaves of cloned lilacs.
Where is the species found?
States & Provinces
AR, BC, CO, CT, DC, IA, IL, IN, KS, KY, MA, MD, ME, MI, MN, MO, NB, NC, NH, NJ, NS, NY, OH, ON, OR, PA, PE, QC, RI, SD, SK, TN, UT, VA, VT, WA, WI, WV
Special Considerations for Observing

When to Start Observations: In the middle of winter, lilac buds are desiccated (dried out) and appear somewhat shriveled (mid-winter bud). In late winter, after conditions begin to warm, the buds hydrate (swell due to becoming moist), and the tips open slightly (late winter bud). The best way to know when to start looking for the first emerging leaves is to watch for these two events. Once the buds have swelled and the bud ends are slightly open and a bit green, the next round of warm weather can force the first leaves to emerge.

Monarch Watch participants should observe the "open flowers" phenophase.
Which phenophases should I observe?
Do you see...?
Leaves Breaking leaf buds View Phenophase Image
In at least 3 locations on the plant, a breaking leaf bud is visible. A leaf bud is considered "breaking" once the widest part of the newly emerging leaf has grown beyond the ends of its opening winter bud scales, but before it has fully emerged to expose the leaf stalk (petiole) or leaf base. The leaf is distinguished by its prominent midrib and veins. (This phenophase was previously called "First leaf".)
More...


All leaf buds broken View Phenophase Image
For the whole plant, the widest part of a new leaf has emerged from virtually all (95-100%) of the actively growing leaf buds. (This phenophase was previously called "Full leaf out".)
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Flowers Open flowers View Phenophase Image
For the whole plant, at least half (50%) of the flower clusters have at least one open fresh flower. The lilac flower cluster is a grouping of many, small individual flowers. (This phenophase was previously called "First bloom".)


Full flowering View Phenophase Image
For the whole plant, virtually all (95-100%) of the flower clusters no longer have any unopened flowers, but many of the flowers are still fresh and have not withered. (This phenophase was previously called "Full bloom".)


End of flowering
For the whole plant, virtually all (95-100%) of the flowers have withered or dried up and the floral display has ended. (This phenophase was previously called "End of bloom".)
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What do these phenophases look like?

The following Phenophase Photo Guides for this species have been vetted for accuracy by the USA-NPN National Coordinating Office. Most photo guides are developed for a particular local or regional monitoring effort, and some of the content may not apply to your effort or your region. However, we make them available to provide as much help as they may in illustrating phenophases for this species. If you have high quality phenophase photos that you are willing to share with us, please visit the Phenophase Photo Guidelines page.

Be aware there is variation from individual to individual within a species, especially across different regions, so your plant may not look exactly like the one pictured.

Since they do not always include complete definitions for the species, use these photo guides ONLY in conjunction with the official Nature's Notebook phenophase defintions included in the table above, in the phenophase definition sheet that downloads with the datasheet, or in the Observe screen in the mobile app.

USDA PLANTS profile for common lilac (USDA Symbol: SYVU )