Every spring for the past eight years, I have been searching for this shrub. And every year, I am both disappointed and bewildered why Persian lilacs are not more readily found in our Bay Area nurseries. This year, I started my search early and resulted to ordering them direct from a local grower, and now that I found them, I feel it is time to share with readers why I covet this species.
We will start with what is available. The most common Syringa in nurseries is S. vulgaris, and for good reason also known as common lilac. Nearly every retail nursery will be bringing them into inventory in early spring when the buds are about to burst open with color and fragrance. Numerous cultivars make it a popular choice. So popular that one can find old shrubs on Victorian properties, or in our case, on the back slope of our Mid-Century Modern home...completely out of place with the design aesthetic but pretty and fragrant nonetheless. S. vulgaris has adapted to our climate, but it was not long ago that people would opt to pile buckets of ice around their bases over winter to induce greater chill. I, however, have not seen any evidence that this actually works. I never do anything with the one we have, and it blooms without fail every year. While common lilacs prevail in nurseries, I still wonder why our subject species is difficult to find given its qualities more suited for California.
As its name suggests, Syringa x persica, or Persian lilac, is drought tolerant due to what is thought of as its origins from S. x afghani and S. x lacinata, suggesting the Middle East. While S. vulgaris is also drought tolerant, I find it exhibits some stress if deprived of water for too long. I have not observed such challenges to growing S. x persica, so I value it more for its healthy performance under stressful drought conditions.
To compare this shrub with common lilacs is unfair to its uniqueness. Admittedly, the competition outshines in showy floral displays with profuse, dense blooms that are also larger than those found on Persian lilacs. Instead, one will find delicate lavender flowers on loose spikes that might arch outward on willowy limbs. Its fragrance is undeniable. Reaching about six feet in size, Persian lilacs provide informal structure to the garden that could act as a backdrop when not stealing the show with its spring color and perfume.
Below is helpful guidance for general lilac pruning by the University of Maine Cooperative Extension's Margorie Peronto.
facts
Botanical Name: Syringa x persica
Syringa: Greek, syrinx, for pipe, in reference to its hallow stems
Persica: Associated with Persia
Common Name: Persian lilac
Family Name: Oleaceae
Origin: Cross, possibly of S. x afghanica and S. x laciniata
design considerations
Positioning: Background
Garden Themes: Mediterranean/drought, urban/suburban residential, cottage, pollinator, children, cutting
Uses: Large informal, shrub border, deciduous screen/privacy, floriculture, mass, specimen
identifying characteristics
Type: Deciduous shrub
Form: Arching vase, upright, round
Texture: Medium
Size: 6' wide by 6' tall but may slightly vary
Outstanding Feature(s): Flower
Stem: Light tan
Leaf:
Type: Simple
Arrangement: Opposite
Shape: Lanceolate
Margin: Entire
Color: Light to medium green
Surface: Glabrous
Flower: Spring. Small but loose panicles of light lavender 4-petaled blooms. Showy and fragrant. Sets on previous year's growth.
Fruit: Autumn. Small, brown capsule.
cultural requirements, tolerances & problems
Sunset Zones: A2, A3; 2-12, 14-16, 18-22
USDA Zones: 4-7
Light: Full sun to light shade
WUCOLS SF Bay Area Hydro Zone: Low
Soil:
Texture: Loam
Moisture Retention: Well-drained
pH: Slightly acidic to slightly alkaline
Tolerances: Urban environments, heat, deer
Problems:
Branch Strength: Medium, flexible
Insects: Scale, borers, leaf miners, caterpillars
Disease: Mildew, blight, leaf spot, wilt, ring rot
citations & attributions
Bayton, R. (2019). The Royal Horticultural Society's the Gardener's Botanical: An Encyclopedia of Latin Plant Names. London: Mitchell Beazley.
Breen, P. "Landscape Plants." College of Agricultural Sciences, Department of Horticulture, Oregon State University, Corvalis. Accessed on March 11, 2022, from https://landscapeplants.oregonstate.edu/plants/syringa-persica.
Extension Gardener. "Syringa x persica." North Carolina State University, Raleigh. Accessed on Marth 11, 2022, from https://plants.ces.ncsu.edu/plants/syringa-x-persica/.
Norris Brenzel, K. (Ed.). (2012). The New Sunset Western Garden Book. New York: Time Home Entertainment, Inc.
Plant Finder. "Syringa x persica." Missouri Botanical Garden, St. Louis. Accessed on March 11, 2022, from https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=282949.
Water Use Classification of Landscape Species. "WUCOLS IV Plant List." University of California, Division of Agriculture and Natural Resources, Davis. Accessed on March 7, 2022, from https://ucanr.edu/sites/WUCOLS/files/183488.pdf.
Photos:
Flower feature: "Syringa persica kz2" by Kenraiz is licensed under Creative Commons-Share Alike 4.0 International.
Botanical illustration: "Persian lilac (Lilac persica) illustration from Traité des Arbr" by Pierre-Joseph Redouté and Henri-Louis Duhamel du Monceau, uploaded by Rawpixel, Ltd. is licensed under Creative Commons Generic 2.0.
Shrub: "Syringa persica kz1" by Kenraiz is licensed under Creative Commons-Share Alike 4.0 International.
All other photos by TELCS.