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Philadelphus

Philadelphus is a genus comprising approximately 60–65 species of deciduous shrubs in the family Hydrangeaceae, native to regions spanning North and Central America, Europe, Asia, and the Himalayas, and commonly known as mock oranges due to their fragrant, white flowers that resemble orange blossoms.^[1]^[2] These shrubs typically grow to heights of 1 to 6 meters, featuring simple, opposite leaves that are often oval or elliptical and may be toothed or entire; most are deciduous, though some southern species such as Philadelphus karwinskyanus are evergreen or semi-evergreen in mild climates.^[3]^[4]^[5] The genus name Philadelphus derives from the Greek term meaning "brother-loving," honoring Ptolemy II Philadelphus, the Egyptian king from 309–246 BCE.^[4] The defining characteristic of Philadelphus species is their showy, bowl-shaped flowers, usually white and four-petaled, which bloom in late spring to early summer, either solitary or in small clusters, and emit a strong, citrus-like fragrance that has made them popular in ornamental gardening.^[3]^[6] Many cultivars and hybrids, such as those derived from Philadelphus × virginalis, have been developed for enhanced flower size, fragrance, and compact growth, thriving in USDA hardiness zones 4 to 9 on well-drained soils in full sun to partial shade.^[7]^[2] While most species are valued for their aesthetic and aromatic qualities in landscapes, some native varieties like Philadelphus lewisii play ecological roles in supporting pollinators in their temperate habitats.^[8]^[9]

Taxonomy and Etymology

Name Origin

The genus name Philadelphus derives from the Greek word philadelphos, meaning "brother-loving," a term reflecting the epithet of Ptolemy II Philadelphus, the Macedonian king of Egypt who ruled from 285 to 246 BCE and was known for his sibling marriage to Arsinoe II.^[10]^[11] Carl Linnaeus formally established the genus in his 1753 Species Plantarum, honoring the pharaoh possibly due to the plant's fragrant flowers evoking the incense of ancient Alexandria.^[10] The common name "mock orange" arises from the flowers' visual similarity to those of citrus species like Citrus sinensis and their jasmine-like fragrance, which mimics orange blossoms without producing edible fruit.^[11] Historically, the name "syringa" was misapplied to Philadelphus species, derived from the Greek syrinx (pipe or tube) in reference to the hollow stems suitable for making pipes; this nomenclature was later correctly reassigned to the lilac genus Syringa.^[12] As of 2025, the dynamic nature of Philadelphus nomenclature continues with ongoing discoveries of new species in the mountains of northern Mexico, including forms like P. maculatus and P. sargentiana, which are being introduced to cultivation from recent seed collections.^[13]

Classification

Philadelphus belongs to the family Hydrangeaceae, within the subfamily Hydrangeoideae and tribe Philadelpheae.^[14] The genus encompasses approximately 60 species of shrubs, primarily distributed across temperate regions of the Northern Hemisphere.^[15] The genus was first formally described by Carl Linnaeus in his Species Plantarum (1753), with Philadelphus coronarius as the type species.^[16] Early classifications placed it variably within Saxifragaceae before its stable assignment to Hydrangeaceae. A pivotal taxonomic revision came from Shiu-ying Hu's comprehensive monograph (1954–1956), which recognized 62 species and established subgeneric divisions into sections such as Philadelphus, Langeria, and Macrocalyx. These sections were delineated primarily on morphological traits of the flowers—such as calyx size, petal arrangement, and stamen characteristics—and seeds, including testa sculpturing and wing presence.^[17] Molecular phylogenetic studies have refined this framework, initially challenging Hu's morphology-based groupings. A 2013 analysis using ITS and plastid trnL-F sequences indicated paraphyly of Philadelphus, with the monotypic Carpenteria (endemic to California) nested within, and revealed three major lineages: one in western North America, another in eastern North America, and a third in Asia.^[18] Post-2020 DNA analyses, incorporating complete chloroplast genomes, have upheld the monophyly of Philadelphus (excluding Carpenteria as a distinct genus) and clarified evolutionary relationships, showing that North American clades diverged early from Asian ones, with the latter exhibiting subclades where eastern and northern Chinese species cluster closely with central Chinese taxa, separate from southwestern Chinese groups. These updates underscore intercontinental disjunctions driven by historical biogeographic events.

Botanical Description

Growth Habit

Philadelphus species are primarily deciduous shrubs, though certain taxa such as P. madrensis and P. palmeri exhibit semi-evergreen foliage in mild climates. They form multi-stemmed bushes typically reaching 1 to 6 meters in height, with stems that are erect, ascending, arching, or spreading and often decussately branched. Twigs are glabrous or bear simple trichomes, contributing to a variable texture across the genus.^[19]^[20]^[21]^[22] The bark is thin and tight on young stems, becoming exfoliating in grayish, brown, or reddish-brown sheets or strips on older growth, ranging from greenish on new twigs to gray-brown overall. Leaves are arranged oppositely, simple, and range from ovate, elliptic-ovate, elliptic, suborbiculate, lanceolate, or linear-lanceolate in shape, measuring 1 to 14 cm in length depending on the species. Margins are entire, serrulate to serrate, and often irregularly variable, with plane or revolute edges; pubescence varies, frequently present on the undersides or along veins, giving a sometimes woolly or strigose appearance.^[19]^[23]^[24]^[19] Growth habit varies notably among species; for instance, P. microphyllus (littleleaf mock orange) forms compact shrubs 0.9 to 2 meters tall with smaller leaves (0.8 to 3 cm long) that are glabrous or strigose. In contrast, P. laxus displays a more spreading form, with arching branches that contribute to a broader silhouette compared to the upright habits of species like P. lewisii. These differences in stature and branching pattern allow adaptation to diverse environmental conditions within the genus's native ranges.^[22]^[25]^[19]

Flowers and Fruits

The flowers of Philadelphus are bisexual and perigynous to epigynous, typically arranged in terminal inflorescences that form cymes, cymose racemes, or panicles, or occasionally solitary, with 1–49 flowers per cluster.^[19] Each flower measures 2–5 cm in diameter, featuring four persistent sepals that are deltate to triangular-acuminate and either villous, strigose, or glabrous, alongside four imbricate petals that are white to cream-colored, oblong-obovate to orbiculate, and sessile or minutely clawed.^[19] Rarely, petals exhibit purple maculations or a pinkish tint in certain species.^[19] The numerous stamens, ranging from 13 to 90, have distinct or proximally connate filaments that are flattened, with depressed-ovate or transversely oblong anthers that are typically yellow.^[19]^[26] A distinctive feature of many Philadelphus flowers is their strong fragrance, attributed to volatile organic compounds such as those identified in essential oils extracted from species like P. coronarius, including monoterpenes and sesquiterpenes that contribute to the characteristic sweet, citrus-like scent.^[27] The pistil consists of a 4-carpellate ovary that is inferior to half-inferior and 4-locular, with one or four styles connate proximally and four stigmas.^[19] Pollination occurs primarily through insect vectors, including bees and syrphid flies, drawn to the fragrant blooms and exposed nectar.^[28] Following pollination, fruits develop as dehiscent capsules that are turbinate to oblong-ovoid, coriaceous, and exhibit loculicidal dehiscence, measuring 5–20 mm in length.^[19] Each capsule contains numerous small seeds, typically more than 10 per locule, which are rusty brown, fusiform, and may feature winged or caudate (tail-like) structures in some species, or carunculate appendages resembling arils in others, aiding dispersal.^[19]^[29]^[22]

Distribution and Ecology

Native Ranges

Philadelphus species are native to regions across the Northern Hemisphere, including North America from Mexico northward to Canada, Central America extending south to Panama, eastern Asia encompassing China, Japan, and adjacent areas, and southeastern Europe including the Caucasus.^[19]^[16] The genus exhibits a relictual and disjunct distribution pattern, with biogeographic evidence pointing to migrations during the Tertiary period that connected these now-separated areas through ancient land bridges and climate shifts in the northern temperate zones.^[18] Centers of diversity for Philadelphus are concentrated in the southwestern United States and Mexico, where approximately 40 species occur, reflecting high endemism in montane and arid habitats, and in eastern Asia, home to about 27 species primarily in northeastern regions.^[30] Recent explorations continue to uncover additional species in the Mexican highlands, with ongoing discoveries reported in northern mountain ranges as of 2025.^[13] While native distributions remain focused in these areas, Philadelphus has been widely introduced to temperate zones worldwide as ornamental shrubs, with some species naturalizing outside their ranges, such as P. coronarius in parts of Europe where it persists in disturbed habitats.^[31]

Ecological Interactions

Philadelphus species play a key role in supporting pollinator communities by providing nectar and pollen from their showy white flowers, which bloom in spring and early summer. These fragrant blooms attract a range of insects, including bees and butterflies, serving as an essential early-season resource in temperate and montane ecosystems. For instance, Philadelphus lewisii is particularly noted for drawing native bees, butterflies, and even moths to its nectar-rich flowers, enhancing pollination services for surrounding flora.^[32]^[33] The genus also supports herbivorous insects, functioning as a larval host for certain Lepidoptera. Species such as P. lewisii provide foliage for caterpillars of native moths and skippers, including the common checkered-skipper (Pyrgus communis), contributing to the biodiversity of insect populations in woodland and shrubland habitats. This interaction underscores Philadelphus's value in food webs, where it sustains herbivore life cycles while potentially facing browsing pressure from these larvae.^[34]^[35] Pathogens pose significant threats to Philadelphus, particularly in wet conditions. Bacterial blight, caused by Pseudomonas syringae pv. philadelphi, infects species like P. coronarius, resulting in necrotic leaf spots and flower blights that can weaken plants during cool, moist springs. Additionally, in humid climates, fungal pathogens such as powdery mildew (Erysiphe spp.) proliferate, forming white powdery coatings on leaves and stems under high humidity and poor ventilation, potentially reducing vigor and aesthetics.^[36]^[37]^[38] In ecological succession, Philadelphus acts as a pioneer shrub in disturbed landscapes, helping to stabilize soils on steep slopes and riparian banks through its extensive root systems. P. lewisii, for example, is commonly used in restoration projects to prevent erosion and facilitate community reassembly in post-disturbance sites. Certain species demonstrate fire-adaptive strategies, resprouting vigorously from root crowns after burns, which aids recovery in fire-prone shrublands akin to chaparral ecosystems.^[39]^[33]

Cultivation

History and Propagation

Philadelphus species were introduced to European cultivation in the 16th century, with P. coronarius, native to the North Caucasus, Transcaucasia, and Turkey, recorded in British gardens by 1597 in John Gerard's herbal collection.^[40]^[41] This species, also known as sweet mock-orange, was introduced to cultivation in southern Europe in the 16th century but gained widespread popularity across Europe by the 1700s for its fragrant white flowers and arching growth habit.^[42] A significant hybridization boom occurred in the 19th and 20th centuries, driven by European breeders seeking improved fragrance, flower size, and form. French nurseryman Victor Lemoine initiated key developments in 1883 by crossing P. coronarius with the compact American species P. microphyllus, producing the influential P. × lemoinei group of hybrids, which formed the basis for many subsequent cultivars.^[43] This era saw dozens of hybrids emerge from nurseries in France, England, and the United States, enhancing ornamental value through double flowers and extended bloom periods. Recent breeding efforts continue to focus on fragrance and compactness, exemplified by the 2024 introduction of Swan Lake® (P. 'ORSTPHILx1'), a sterile hybrid selected for its profuse, sweetly scented blooms and rounded habit suitable for modern landscapes.^[44] Propagation of Philadelphus is primarily vegetative due to hybridization complexities, though seeds can be used for species. Softwood cuttings, taken in early summer from new growth, root readily when treated with rooting hormone and placed in a moist, well-drained medium under high humidity.^[45] Semi-hardwood cuttings collected in late summer or early fall provide another reliable method, often succeeding at rates above 80% with bottom heat.^[46] Layering, particularly simple or tip layering in spring or fall, encourages rooting along buried stems and is effective for establishing new plants directly in the garden.^[22] For seed propagation, fresh seeds require cold stratification at 4–5°C for 60–90 days to break dormancy and achieve germination rates of 50–70% in a sterile, sandy medium.^[47] Challenges in propagation arise from the prevalence of sterile hybrids, which do not produce viable seeds and must rely on clonal methods like cuttings or layering to maintain desirable traits.^[48] For rare or difficult-to-root taxa, such as littleleaf mock-orange (P. microphyllus), tissue culture via axillary shoot micropropagation offers a solution, enabling mass production despite low success with traditional cuttings or seeds.^[49]

Garden Requirements

Philadelphus species thrive in sites with full sun to partial shade, where they produce the most abundant and fragrant blooms, though they can tolerate light shade with reduced flowering. These deciduous shrubs are hardy in USDA zones 4 through 9, enduring cold winters down to -30°F (-34°C) and moderate summer heat, making them suitable for a wide range of temperate climates.^[50]^[51] For optimal growth, Philadelphus requires well-drained soils that are neutral to slightly acidic, with a pH range of 6.0 to 7.0, though they adapt to a broader spectrum from mildly acidic to mildly alkaline conditions. They perform well in loamy, sandy, or clay soils as long as drainage is adequate to prevent root rot, and they dislike heavy, waterlogged sites.^[52]^[53] Once established, Philadelphus is drought-tolerant and needs minimal supplemental watering except during prolonged dry spells in the first year after planting. Applying a 2- to 3-inch layer of organic mulch around the base helps retain soil moisture, suppress weeds, and regulate root zone temperatures.^[54] Pruning should occur immediately after flowering in late spring or early summer to maintain shape, encourage new growth, and remove dead or crossing branches, as blooms form on the previous year's wood. Light annual trimming promotes air circulation and rejuvenates older plants by cutting back up to one-third of the oldest stems to the ground.^[23] Common pests include aphids, which cluster on new growth and cause leaf curling, and scale insects, which appear as small bumps on stems and excrete sticky honeydew. These can be managed through horticultural oils, insecticidal soaps, or encouraging natural predators like ladybugs, with infestations rarely severe in healthy plants.^[55]^[56] Philadelphus is highly adaptable for garden use, excelling in mixed borders, informal hedges, or naturalistic plantings where its arching form and summer fragrance enhance landscapes. Its low water requirements make it ideal for xeriscapes or low-maintenance areas once rooted.^[52]^[57]

Notable Cultivars

Among the most esteemed cultivars of Philadelphus are those recognized by the Royal Horticultural Society (RHS) with the Award of Garden Merit (AGM), selected for their outstanding performance in gardens, including reliable flowering and fragrance. These include 'Belle Étoile', a semi-double flowered variety with pure white petals and maroon centers, producing abundant blooms up to 4 cm wide in early summer on upright stems reaching 1.5-2 m tall.^[58] 'Innocence' features pure white, semi-double flowers with a strong orange-blossom scent, complemented by variegated yellow-and-green foliage on a bushy shrub growing to 2.5 m.^[59]^[60] The dwarf 'Manteau d'Hermine' is particularly valued for small gardens, forming a compact mound to 0.8 m tall and wide, covered in double creamy-white flowers that emit a sweet fragrance.^[61]^[62] Key hybrid groups have shaped modern Philadelphus cultivation, with P. × virginalis, developed by Victor Lemoine in the early 20th century, renowned for its intense fragrance derived from crosses involving P. × lemoinei and P. nivalis.^[63] Complementing this, the P. × lemoinei group, originating from Lemoine's crosses around 1883 between P. coronarius and P. microphyllus, is prized for its vigorous growth and profuse flowering on shrubs typically 1.2-2 m tall.^[43]^[64] Recent innovations highlight ongoing breeding for enhanced adaptability. 'Swan Lake®' (P. 'ORSTPHILx1'), introduced in 2024, features glossy young foliage and profuse clusters of fragrant white flowers on a compact, rounded form reaching 1.5 m, bred for drought tolerance and extended bloom duration.^[44] Similarly, 'Snowbelle' offers a compact habit ideal for small gardens or containers, growing to 1-1.2 m with double white flowers that provide a prolonged display and strong citrus-like scent.^[65]^[66] In 2025, Philadelphus 'Petite Perfume Pink' was introduced as the first pink-flowered cultivar, winning the RHS Chelsea Flower Show Plant of the Year on May 20, 2025. Bred by Alan Postill and launched by Hillier Nurseries, it features a compact habit (1.5 m tall and wide), spectacular fragrance, and low-maintenance growth with no pruning required.^[67]^[68] Cultivar selection emphasizes fragrance intensity, often likened to orange blossoms, alongside bloom duration of 3-4 weeks and resistance to common issues like powdery mildew, ensuring low-maintenance appeal in diverse landscapes.

Cultural Significance

Symbolism and Uses

Philadelphus lewisii, commonly known as Lewis' mock orange or syringa, serves as the state flower of Idaho, officially adopted in 1931 to symbolize the state's rugged natural beauty and pioneer heritage.^[69] The species name lewisii honors Meriwether Lewis of the Lewis and Clark Expedition, who first documented and collected the plant in 1806 during their return journey through what is now Idaho.^[70] This designation ties the genus to American exploration history, representing resilience and discovery in the American West.^[71] The fragrant branches and flowers of Philadelphus species have long been utilized in traditional practices, particularly for their citrus-like scent reminiscent of orange blossoms. Cut branches are commonly incorporated into floral arrangements and bouquets for their long-lasting fragrance and elegant white blooms, enhancing both fresh and dried displays.^[72] Additionally, indigenous peoples have employed occasional medicinal applications, such as preparing a decoction from branches and flowers as a soaking solution for sore chests and respiratory discomfort, though these uses lack modern scientific validation.^[73] A poultice of bruised leaves has also been applied topically to treat infections and skin conditions like eczema.^[74] In ecological contexts, Philadelphus shrubs provide valuable wildlife habitat, offering dense cover and nesting sites for birds such as finches, wrens, and small songbirds, while their seeds serve as a food source in late summer and winter.^[28] Their extensive root systems make them effective for erosion control in native plantings, particularly along riparian zones and slopes, stabilizing soil in disturbed habitats.^[35] These roles underscore the genus's contribution to biodiversity and land restoration efforts.^[75] Symbolically, Philadelphus flowers in Victorian floriography represent deceit or counterfeit beauty, stemming from the "mock" in their common name despite their appealing fragrance and appearance. In modern interpretations, however, they evoke purity, sweetness, and nostalgia, attributed to their pristine white petals and citrus-like scent that mimics orange blossoms.^[76]^[77]

In Literature and Art

Philadelphus, commonly known as mock orange, has been a recurring motif in literature, symbolizing complex emotions through its evocative fragrance and floral form. In Louise Glück's poem "Mock Orange," published in her 1975 collection The House on Marshland, the plant's scent permeates the narrative as a metaphor for unfulfilled desire and relational disillusionment, with the speaker expressing visceral hatred toward the flowers akin to disdain for intimacy, underscoring themes of sensuality and profound disappointment.^[78] In visual art, Philadelphus features prominently in 19th-century botanical illustrations, where its delicate white blooms were meticulously rendered to highlight scientific and aesthetic appeal. Pierre-Joseph Redouté's stipple engravings, such as those in Henri Louis Duhamel du Monceau's Traité des arbres et arbustes (circa 1801–1819), depict Philadelphus coronarius with exquisite detail, emphasizing the flower's structure and fragrance-implying allure for horticultural documentation. Later, in Impressionist works, the shrub appears in garden still lifes, capturing its role in domestic natural beauty; Camille Pissarro's Still Life with Peonies and Mock Orange (1872–1877) showcases clusters of the fragrant blooms alongside vibrant peonies, using loose brushwork to evoke the ephemeral quality of summer gardens.^[79] Modern references in gardening literature often celebrate Philadelphus for its intoxicating citrus-like fragrance, positioning it as an essential element for sensory-rich landscapes. For instance, descriptions highlight its "devastatingly delicious" scent as a highlight of early summer, rivaling more exotic blooms in evocative power.^[80] In 2025, arboreta emphasized the genus's versatility through dedicated displays, such as Whitehouse Farm Garden and Arboretum's showcase of diverse cultivars for midsummer interest and adaptability in various garden settings.^[13] This recognition culminated in the Royal Horticultural Society awarding Philadelphus 'Petite Perfume Pink' as Plant of the Year, praising its compact form and spectacular fragrance for both small and large gardens.^[67] The jasmine-like scent of Philadelphus frequently evokes nostalgia in prose, serving as a sensory trigger for personal reminiscences in a manner reminiscent of Proustian involuntary memory. In reflective essays, the flower's aroma recalls childhood gardens or lost familial connections, transforming the plant into a vessel for bittersweet temporal reflection.^[81]

Selected Species

North American Species

Philadelphus lewisii, commonly known as Lewis' mock orange, is native to the Pacific Northwest region of North America, ranging from southern British Columbia through Washington, Oregon, Idaho, and into northern California and Montana.^[82] This deciduous shrub typically grows 1.5 to 3 meters tall with an upright to arching habit, featuring opposite, ovate leaves and clusters of fragrant white flowers in late spring to early summer.^[8] It thrives in diverse habitats including riparian zones, forest edges, dry hillsides, and chaparral, often in moist to well-drained soils.^[33] Designated as the state flower of Idaho, it holds cultural significance and supports pollinators with its nectar-rich blooms.^[39] Philadelphus mexicanus, or Mexican mock orange, is endemic to Mexico and extends into Central America, primarily occurring in subtropical regions as a scrambling evergreen shrub up to 2 meters tall.^[83] It features oval leaves and solitary, cup-shaped creamy-white flowers with a rose-like fragrance, blooming in spring and summer on arching branches.^[84] Adapted to well-drained, sunny environments, it grows in rocky or forested slopes but remains rare in cultivation outside mild climates due to its tenderness.^[85] Philadelphus laxus, a synonym for Philadelphus inodorus or scentless mock orange, is restricted to the southeastern United States, from Virginia and Kentucky southward to northern Florida, Georgia, Alabama, and Mississippi.^[86] This deciduous shrub reaches 2 to 4 meters with an arching, loosely branched form, bearing unscented white flowers in terminal clusters during late spring.^[87] It inhabits moist rocky woodlands, stream banks, and limestone hammocks, preferring calcareous soils, though populations in Florida's panhandle are sparse and face threats from habitat loss and fragmentation.^[88] Listed as critically imperiled in parts of its range, including Georgia, conservation efforts focus on protecting remaining bluff and ravine sites.^[89] Philadelphus pubescens, known as hoary mock orange, occurs in the eastern United States along the Mississippi embayment and south-central states, including Alabama, Arkansas, Georgia, and Tennessee, with scattered introductions northward.^[90] A deciduous shrub growing 3 to 6 meters tall, it is distinguished by its softly hairy, downy leaves and stems, along with white, mildly fragrant flowers in summer racemes.^[91] Found on limestone river bluffs, rocky slopes, and wooded edges in calcareous habitats, it is adapted to moderately dry conditions.^[92] Conservation status varies regionally, with it considered extinct in Illinois, critically imperiled in Georgia, and rare in New York due to habitat destruction and limited distribution.^[93]

Asian and European Species

The Asian and European species of Philadelphus are distributed across temperate regions of Eurasia, where they typically inhabit woodlands, thickets, rocky slopes, and montane areas, often displaying strong fragrance in their flowers as an adaptation to attract pollinators in these environments. Unlike some New World species, many Eurasian taxa emphasize upright or arching growth forms suited to seasonal climates with cold winters, contributing to the genus's overall diversity through variations in leaf texture and flowering timing. Philadelphus coronarius, native to southeastern Europe, the Caucasus, and northeastern Turkey (Asia Minor), is a deciduous shrub reaching 3 m in height with arching branches. It features opposite, ovate to lanceolate leaves, 3–8 cm long, and produces abundant clusters of highly fragrant white flowers, each 2–3 cm across with four petals and prominent yellow anthers, blooming in late spring to early summer. This species thrives in open woodlands, scrub, and rocky habitats, and has been widely introduced beyond its native range for its ornamental fragrance.^[94]^[95]^[96]^[97] Philadelphus schrenkii, endemic to Central Asian regions including eastern Siberia, northeastern China, and Korea, forms an upright deciduous shrub up to 4 m tall with elliptic leaves and peeling bark. It bears clusters of 5–7 fragrant, creamy-white flowers, each about 3 cm wide with yellow anthers, in early summer, setting it apart by its vigorous growth and early flowering. The species occurs in mixed forests and woodland edges, preferring well-drained soils and partial shade.^[23]^[98]^[99] Philadelphus pekinensis is native to northern and western China as well as Korea, where it grows as a compact deciduous shrub to 2 m in mixed forests, thickets, and mountain slopes. It has lanceolate leaves up to 7 cm long and produces terminal clusters of fragrant white flowers, 2–3 cm across, during summer, valued in traditional East Asian landscapes for its dense form and scent. In milder conditions, it may retain some foliage late into the season.^[100]^[101] Philadelphus incanus, found in central China extending to Henan province, is a montane shrub adapted to temperate forest slopes and rocky areas. It is distinguished by its hairy elliptic leaves and produces white flowers in summer clusters, contributing to its ecological role in understory layers.^[102]

Hybrids

Hybrids within the genus Philadelphus primarily result from crosses between Old World (European) and New World (North American) species, combining traits such as fragrance, flower size, and growth habit for ornamental purposes. These interspecific and pancontinental hybrids often exhibit enhanced floral displays compared to their parents, though many are sterile due to ploidy differences. Notable examples include P. × virginalis and P. × lemoinei, which have been widely propagated since the late 19th and early 20th centuries.^[43] The hybrid Philadelphus × virginalis originates from a cross between P. × lemoinei and the double-flowered form of P. × nivalis, combining traits from European and North American species, resulting in semi-double to double-flowered shrubs that typically reach 2.5–3 meters in height with an upright, arching form. Developed around 1909, this hybrid group produces fragrant white blooms in clusters, with cultivars like 'Virginal' featuring fully double flowers up to 4 cm across, enhancing their garden appeal. Other selections in this group, such as 'Girandole' and 'Argentine', similarly emphasize doubled petals and prolonged flowering periods of about 10 days.^[63]^[7]^[43] Another prominent hybrid series is Philadelphus × lemoinei, created in 1884 by French nurseryman Victor Lemoine through the cross of P. coronarius (European) and P. microphyllus (North American), yielding compact shrubs 1.2–2.4 meters tall with small, intensely fragrant single or semi-double white flowers measuring 2–3 cm wide. These hybrids are valued for their dense, bushy growth and suitability for smaller gardens, with leaves typically 3–6 cm long and sparsely toothed. Cultivars like 'Belle Étoile' and 'Innocence' exemplify the group's traits, offering reliable blooming in early summer and resistance to legginess.^[103]^[64]^[104] Sterility is common among Philadelphus hybrids, particularly triploids arising from unequal chromosome contributions in crosses between diploid parents from Old and New World lineages, where Philadelphus species maintain a base chromosome number of 2n=26. For instance, 'Belle Étoile' and 'Bicolore' are confirmed triploids, rendering them seedless and non-invasive, a desirable trait for cultivation. This triploidy often stems from unreduced gametes in one parent, leading to partial or complete sterility that prevents unwanted spread.^[43]^[105]^[106] Recent breeding efforts have introduced improved hybrids, such as Philadelphus 'ORSTPHILx1' (Swan Lake®), an interspecific cross released in 2024 from Oregon State University, featuring a compact form reaching 1.8 meters tall and wide, abundant fragrant double white flowers with a fruity scent, and vigorous growth suitable for USDA zones 4–8. This hybrid emphasizes high flower production and reblooming potential, addressing limitations in older cultivars like reduced vigor.^[44]^[107] Most Philadelphus hybrids are cultivated ornamentals in temperate regions worldwide, thriving in USDA zones 4–8, but some have escaped into natural areas as local populations in North America and Europe, particularly in disturbed woodlands or along streams. These escapes remain limited due to sterility in many clones, minimizing ecological impact compared to fertile species.^[19]

References

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Species: Philadelphus spp. - Woody Plants Database
There are at least 60 species (many of the species are not found in cultivation), cultivars, and varieties of this genus.
[2]
https://trees.umn.edu/mock-orange-philadelphus-spp
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MOCK ORANGE - PHILADELPHUS SPP. | The UFOR Nursery & Lab
Common Name: mock orange. Scientific Name: Family: Hydrangeaceae Genus: Philadelphus Species: spp. Hardiness Zone: 4 to 9. Height: 2 to 10 ft
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Species In Genus: +- 65 species: temperate America, Eurasia. Etymology: (Greek: for Ptolemy Philadelphus, Greek king of Egypt, 309--247 BC) Note: Many ...
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Philadelphus × virginalis - Plant Finder - Missouri Botanical Garden
Philadelphus × virginalis, commonly known as virginal mock-orange, is a semi-double to double-flowered deciduous hybrid shrub in the Saxifrage family.
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Philadelphus lewisii | Landscape Plants | Oregon State University
Common name: Wild Mockorange Lewis Mockorange. Pronunciation: fil-a-DEL-fus lu-IS-ei. Family: Hydrangeaceae. Genus: Philadelphus. Type: Broadleaf.
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Fragrance in the Wild Western Garden: Philadelphus
The botanical name of the genus was chosen by Linnaeus, himself ... The reference could well be to Ptolemy II Philadelphus, the Macedonian king of Egypt.Missing: etymology | Show results with:etymology
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Know Your Natives – Hairy Mock Orange
Dec 9, 2021 · The genus name is said to honor Ptolemy II Philadelphus, pharaoh of Egypt (283-246 BC). The specific epithet is Latin for “hairy.” The common ...<|separator|>
[10]
Syringa vulgaris, lilac | Trees of Stanford & Environs
Name derivation: Syringa – probably from Greek syrinx (pipe), in reference to the stems of Philadelphus to which the name was originally applied until ...
[11]
The variety and versatility of Philadelphus
Sep 19, 2025 · New species of Philadelphus are still being discovered today in the mountains of northern Mexico, for example, with new plants growing in ...
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Hydrangeaceae - FNA - Flora of North America
Nov 5, 2020 · Subfamily Hydrangeoideae comprises two tribes: Philadelpheae de Candolle ex Duby and Hydrangeeae de Candolle. North American genera in the former are ...
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[PDF] Philadelphus L. - USDA Forest Service
Chave been placed in several families: Saxifragaceae (Harrington 1954), Hydrangeaceae (Hitchcock and others 1961), and more recently, the Philadelphaceae ( ...Missing: classification taxonomy subfamily Philadelpheae
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Philadelphus L. | Plants of the World Online | Kew Science
Kingdom Plantae · Phylum Streptophyta · Class Equisetopsida · Subclass Magnoliidae · Order. Cornales. View Order Tree opens in a new tab · Family. Hydrangeaceae.Missing: subfamily Philadelpheae
[15]
A monograph of the genus Philadelphus - Biodiversity Heritage Library
A monograph of the genus Philadelphus by Hu, Shiu-Ying. Type: Article. Date of Publication: 1955. Original Publication: Journal of the Arnold Arboretum.
[16]
Molecular phylogenetic analysis suggests paraphyly and early ...
Jun 25, 2013 · Our results suggest that Philadelphus is a paraphyletic group with the monotypic genus Carpenteria nested within. Three major lineages were ...
[17]
Philadelphus - FNA - Flora of North America
Nov 5, 2020 · Flowers bisexual; perianth and androecium perigynous to epigynous; hypanthium completely adnate to ovary, turbinate, obconic, or hemispheric, ...Missing: II | Show results with:II
[18]
Philadelphus madrensis|Sierre Madre mountain mock orange - RHS
Foliage: Deciduous or Semi evergreen ; Habit: Bushy ; Genus. Philadelphus are deciduous shrubs with simple, opposite leaves and bowl-shaped, usually fragrant ...
[19]
Philadelphus palmeri | Pan Global Plants
Philadelphus palmeri. From the Sierra Madre Oriental mountains in NE ... semi-evergreen 'Mock Orange' makes a small shrub with arching branches up to ...
[20]
Philadelphus - Wikipedia
Philadelphus (mock-orange) is a genus of about 60 species of shrubs from 3–20 ft (1–6 m) tall, native to North America, Central America, Asia and (locally) ...Missing: characteristics | Show results with:characteristics
[21]
[PDF] Philadelphus L.: mock orange - USDA Forest Service
Mock orange (Philadelphus spp.) are multi-stemmed, deciduous shrubs with fragrant white flowers, used for revegetation and as ornamentals.
[22]
https://www.fs.usda.gov/rm/pubs_series/wo/wo_ah727/wo_ah727_786_789.pdf
[23]
Philadelphus lewisii: Mock Orange - Portland Nursery
Mock Orange has fragrant white blossoms, arching branches, and grows 4-6 ft. It is a deciduous, multi-stemmed shrub with yellow fall leaves.Missing: habit | Show results with:habit
[24]
https://www.portlandnursery.com/natives/philadelphus
[25]
Philadelphus coronarius - Virginia Tech Dendrology Fact Sheet
Flower: White, four petals, yellow anthers, 1 inch across, fragrant, appearing in early summer. Fruit: Dry, four-parted capsule, 1/2 inch long, persistent. Twig ...
[26]
Volatile compounds in distillates and hexane extracts from the ...
Dec 30, 2024 · The aim of the study was to compare the component composition of volatile compounds of hydrodistillates and hexane extracts from flowers of Philadelphus ...
[27]
Western mock orange (Philadelphus lewisii)
May 27, 2016 · Other pollinators attracted to scent include bees, but also syrphid flies (aka flower flies), which are particularly fond of white and yellow ...
[28]
Philadelphaceae D. Don
Seeds endospermic; small; winged, or wingless. Embryo well differentiated (small). Cotyledons 2. Embryo achlorophyllous (2/7); straight. Physiology ...
[29]
A taxonomic revision of Philadelphus (Hydrangeaceae) in South ...
Sep 1, 2022 · Among the 70 species, 27 are native to Northeast Asia, 22 to China (Huang et al. 2001), three to Russia (Pojarkova 1985), and one to Japan (Ohwi ...Missing: clades | Show results with:clades
[30]
https://www.sciencedirect.com/science/article/pii/S2287884X22000401
[31]
OregonFlora Philadelphus lewisii
Plant Facts · adult butterflies/nectar source · bees and other insect pollinators · beneficial insects/pest eating insects · caterpillar host plant/larval food ...
[32]
[PDF] Lewis mockorange plant fact sheet
Eastern and northern exposures are favored by this species. Classified as fire resistant, it will resprout from root crowns after burning and regenerate from ...
[33]
[PDF] Suggested Native Pollinator Plants From a Garden in Bend
butterflies, moths, caterpillar/larval host plant for Common Checkered-Skipper (Pyrgus ... ○ Mock Orange - (Philadelphus lewisii) mid; white, flat flowers; ...
[34]
Mock Orange - Sparrowhawk Native Plants
Mock orange also has a plethora of habitat values, including attracting bees, butterflies and other insect pollinators to your fruit and vegetable garden.
[35]
Variation within Pseudomonas syringae pv. philadelphi, the cause of ...
S.J.. 1983. Pseudomonas syringae causing a leaf spot and flower blight of mock orange Philadelphus coronarius in England . Plant Pathology. 32. ,. 461. –. 463.
[36]
Mock Orange (Philadelphus spp.)-Bacterial Blight
Cause Pseudomonas syringae pv. syringae and P. s. pv. philadelphi, bacteria that overwinter on stems and buds. The disease is often a problem in years when ...Missing: coronarius | Show results with:coronarius
[37]
Philadelphus coronarius|common mock orange/RHS Gardening
Diseases. May be susceptible to honey fungus (rarely) and powdery mildews. Get involved. The Royal Horticultural Society is the UK's leading gardening charity ...
[38]
[PDF] Philadelphus lewisii Pursh Lewis mock orange HYDRANGEACEAE
Benefits.—Seedlings or larger planting stock of. Lewis mock orange are transplanted into steep, rocky, unstable slopes where they provide soil stabilization ...Missing: succession pioneer
[39]
Philadelphus coronarius – 31st July 2023 – Mock Orange
Jul 31, 2023 · Worldwide, the genus Philadelphus contains around 60 species including many in Asia, while the World Plant List, which includes all known ...
[40]
Philadelphus coronarius L. | Plants of the World Online | Kew Science
Native to: North Caucasus, Transcaucasus, Türkiye. Introduced into: Arkansas, Assam, Austria, Baltic States, Belgium, Central European Russia, Connecticut, ...Missing: origin | Show results with:origin<|control11|><|separator|>
[41]
Philadelphus coronarius (PHICO)[Overview] - EPPO Global Database
Cultivated in southern Europe as an ornamental since ancient times. Introduced in Central Asia, Indochina (Myanmar), eastern USA and Canada.
[42]
Philadelphus coronarius - Trees and Shrubs Online
A shrub up to 12 ft high, with erect stems, the year-old bark brown and peeling; young shoots ribbed. Leaves ovate to oval-lanceolate, broadly wedge-shaped.
[43]
Philadelphus: The Hybrids - Trees and Shrubs Online
Leaves up to 41⁄2 in. long by 2 in. wide, coarsely toothed, often deeply so. A very vigorous, free-flowering hybrid, attaining 10 ft in height, but less in ...
[44]
Philadelphus 'ORSTPHILx1' Swan Lake® Mockorange in
Feb 21, 2024 · Mockorange are deciduous shrubs valued for their adaptability and tolerance to drought as well as their highly fragrant flowers.
[45]
Mock Orange Shrubs: How to Grow Mock Orange - 2025 - MasterClass
Nov 3, 2021 · 1. Plan to take cuttings in the summer. The best time to collect cuttings from an established mock orange plant is during the summer, at the ...
[46]
Propagation techniques / RHS Gardening
Take semi-ripe cuttings in late summer to early autumn when sections of the current season's growth has begun to firm.
[47]
[PDF] Plant Propagation Protocol for Philadelphus lewisii
Propagation Goal (Options: Plants, Cuttings,. Seeds, Bulbs, Somatic Embryos, and/or. Other Propagules):. Can use seeds or vegetative cuttings. Propagation ...
[48]
https://www.parkseed.com/products/philadelphus-pearls-of-perfume-29412
[49]
Optimization of Tissue Culture Medium for Little-leaf Mockorange ...
The need to conserve specific genotypes and the difficulty of seed propagation and stem cutting propagation make axillary shoot micropropagation a good option ...Missing: challenges sterile hybrids
[50]
How to Grow 5 Mock Orange Varieties - The Spruce
Oct 4, 2024 · Philadelphus lewisii 'Blizzard': Particularly tolerant to cold weather, this variety only reaches around 5 feet high by 3 feet wide. ...Missing: Swan Lake 2024
[51]
Mockorange | UMN Extension
(Philadelphus spp.) is a fragrant, white-flowering shrub native to ... Small, non-ornamental, 4-valved woody seed capsules. Growing mockorange. White ...<|control11|><|separator|>
[52]
How to Grow Mock Orange: The Complete Guide | Almanac.com
Mar 21, 2025 · Mock orange shrubs do well in full sun to partial shade. In the hotter portions of their range, a little less sun or filtered sunlight in the afternoon is ...
[53]
https://pfaf.org/user/plant.aspx?LatinName=Philadelphus%20coronarius
[54]
https://www.gardenerspath.com/plants/ornamentals/grow-mock-orange/
[55]
Philadelphus coronarius (Fragrant Mockorange, Golden Mock ...
A rounded shrub in the hydrangea family with stiff, straight ascending arching branches; dense, twiggy; can become leggy so may need to be pruned to shape.
[56]
How to grow philadelphus (mock orange) - Gardeners' World
Oct 21, 2025 · Philadelphus 'White Rock' (RHS AGM) – an upright shrub with cascading stems of fragrant, semi-double blooms. It's well suited to growing in ...Missing: species | Show results with:species
[57]
https://www.whiteflowerfarm.com/how-to-grow-philadelphus-mock-orange
[58]
Philadelphus 'Belle Etoile' (Mock Orange) - Gardenia.net
Recipient of the prestigious Award of Garden Merit of the Royal Horticultural Society. · Grows up to 5-6 ft. · A full sun to light shade lover, this plant is best ...Alternative Plants To... · Philadelphus Lewisii (wild... · Lavandula Angustifolia...
[59]
Philadelphus 'Innocence' (v)|mock orange 'Innocence'/RHS Gardening
A bushy deciduous shrub to 2.5m tall, with arching branches bearing ovate leaves splashed with yellow, and fragrant, cup-shaped white flowers.
[60]
Philadelphus Innocence - Let's Go Planting
RHS Award of Garden Merit · Position: Full sun, partial shade · Soil: Moist, well drained · Growth Rate: Average · Flowering Period: Spring – Summer · Hardiness: H6 ...
[61]
Philadelphus 'Manteau d'Hermine' (d)|mock orange 'Manteau ... - RHS
'Manteau d'Hermine' is a compact small deciduous shrub with relatively small ovate leaves and fragrant, double creamy-white flowers to 4cm in width.
[62]
Philadelphus 'Manteau d'Hermine' (Mock Orange) - Gardenia.net
Recipient of the prestigious Award of Garden Merit of the Royal Horticultural Society. · Grows up to 2-3 ft. · A full sun to light shade lover, this plant is best ...
[63]
Philadelphus × virginalis - Oregon State Landscape Plants
Hardy to USDA Zone 4 The hybrid was developed in 1909 in France by Victor Lemoine (P. ×lemoinei × P. nivalis plenus ?) and introduced as 'Virginal'.Missing: history | Show results with:history
[64]
Philadelphus x lemoinei (Lemoine Mockorange)
This shrub prefers moist well-drained soils in sun to part sun. Prune after flowering to control the size of the shrub and plant near a door to enjoy the ...
[65]
https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=268920
[66]
Snowbelle Philadelphus | Spring Meadow - wholesale liners
Extra useful, thanks to its compact, low growing habit, 'Snowbelle' mockorange is loaded with fragrant, double white flowers in spring. USDA Zone: 4 - 8 (-30 ...
[67]
Idaho State Flower | Syringa
Syringa (Philadelphus lewisii) was designated the official state flower of Idaho in 1931; the species name honors Meriwether Lewis of the Lewis & Clark ...
[68]
Idaho State Flower - The Syringa | Proflowers Blog
Dec 9, 2015 · Lewisii, the species name of the Syringa, honor Meriwether Lewis (from the Lewis and Clark expedition) who wrote about the plant on his travels.History · Fun Fact · Growing Information
[69]
Inside Idaho's state flower and the famous explorer it was named after
Mar 27, 2022 · The flower's scientific name is the Philadelphus lewisii – after Meriwether Lewis of the Lewis and Clark Expedition. It's said that Lewis wrote ...<|control11|><|separator|>
[70]
https://www.proflowers.com/blog/idaho-state-flower-the-syringa
[71]
MOCK ORANGE - Philadelphus lewisii - Medicinal herbs
A strained decoction of the branches, sometimes with the flowers, has been used as a soaking solution in the treatment of sore chests, eczema and bleeding ...Missing: traditional floral arrangements
[72]
Philadelphus lewisii Mock Orange, Lewis' mock orange PFAF Plant ...
Medicinal Uses A poultice of the bruised leaves has been used to treat infected breasts[257]. A strained decoction of the branches, sometimes with the flowers, ...Missing: traditional floral arrangements
[73]
Philadelphus lewisii - Washington Native Plant Society
An upright, loosely-branched, deciduous shrub with large fragrant white flowers which grows along coastal bluffs and rocky slopes, in open forests and disturbed ...
[74]
Mock Orange Flower: Meaning and Symbolism - FloristEmpire
The flowers and leaves of mock orange were incorporated into traditional herbal medicine in Chinese culture. They were valued for their medicinal properties, ...
[75]
Discover the Symbolic Beauty and Uses of Mock Oranges in Floral ...
May 31, 2024 · Mock oranges are a popular choice for weddings primarily due to their symbolism of purity and beauty. Their elegant white blossoms and sweet, ...
[76]
Mock Orange | The Poetry Foundation
We were made fools of. And the scent of mock orange. drifts through the window. How can I rest?
[77]
Camille Pissarro - Vase of Peonies and Mock Orange
Vase with Peonies and Mock Orange was likely created in artistic rivalry with his friend and pupil Paul Cézanne, renowned for his numerous still lifes.
[78]
Mock Orange: Tender but Tough | Portland Monthly
Jun 28, 2012 · Mock orange (Philadelphus) surely tops my list of the world's most devastatingly delicious flower scents. It's sweet but not cloying; penetrating yet in no way ...
[79]
Philadelphus Petite Perfume Pink wins RHS Plant of the Year 2025 ...
May 20, 2025 · The size of 1.5m by 1.5m will make a spectacle in a large garden but is also great for small gardens. The fragrance is absolutely spectacular.
[80]
The scent of nostalgia - Jardin
Aug 2, 2016 · Scent is powerful for recalling the past, like old roses, Brunfelsia pauciflora, mimosa, lavender, and mock-orange, which evoke nostalgic ...Missing: Proustian allusions literature
[81]
Philadelphus lewisii - USDA Forest Service
Leaves on shrubs and succulent herbaceous growth depressed the fire in 1975. A single Lewis' mock orange was followed during the study. The plant was dormant ...
[82]
Philadelphus mexicanus Schltdl. | Plants of the World Online
The native range of this species is Mexico to Central America. It is a scrambling shrub and grows primarily in the subtropical biome. Taxonomy · Images ...
[83]
Philadelphus mexicanus - Trees and Shrubs Online
A handsome and distinct species with rose-scented flowers, not hardy outside the mildest parts unless grown against a warm wall.Missing: diversity | Show results with:diversity
[84]
Philadelphus mexicanus|Mexican mock orange/RHS Gardening
Philadelphus mexicanus. Mexican mock orange. A spreading, evergreen shrubto 2mwith arching branches and oval leaves up to 10cm long.
[85]
Philadelphus inodorus - FNA - Flora of North America
Nov 5, 2020 · Shrubs, 20–40 dm. Stems brown, gray, or stramineous, branched, 20–40 dm, glabrous or very sparsely strigose, especially at nodes; bark reddish, ...
[86]
Philadelphus inodorus (Scentless mock orange) | Native Plants of ...
Oct 20, 2022 · Plant Characteristics. Duration: Perennial Habit: Shrub Leaf Retention: Deciduous Fruit Type: Capsule Size Notes: Up to about 12 feet tall.
[87]
Philadelphus inodorus | NatureServe Explorer
Highly threatened by land-use conversion and habitat fragmentation. Human disturbance presents a low-level threat to this species (Southern Appalachian Species ...
[88]
Philadelphus pubescens - Georgia Biodiversity Portal
Appalachian Mock Orange (Philadelphus inodorus) is found throughout Georgia. Its current-year twigs are hairless but the flower clusters have only 1 - 3 (rarely ...
[89]
hoary mock orange - USDA Plants Database Plant Profile General
General Information, Symbol, Group, Duration, Growth Habits, Native Status, Download Distribution Data, View Print Options
[90]
Philadelphus pubescens (hoary mock-orange) - Go Botany
Philadelphus coronarius: branchlets brown, branches with exfoliating bark, leaf blades abaxially glabrous or pubescent only on the veins and in the axils of ...
[91]
Philadelphus pubescens - Illinois Natural History Survey Plantdb
Status/Listing: Extinct. Notes:According to Ebinger et al. 2010, "Native mock orange is restricted to limestone river bluffs of the Mississippi embayment ...
[92]
Philadelphus pubescens - Species Page - NYFA: New York Flora Atlas
(New York): Rare plants are protected under New York State Environmental Conservation Law section 9-1503. ... A global conservation status rank may be not ...
[93]
https://newyork.plantatlas.usf.edu/Plant.aspx?id=1590
[94]
https://www.mortonarb.org/plant-and-protect/trees-and-plants/sweet-mock-orange/
[95]
Sweet Mock Orange (Philadelphus coronarius) - Easyscape
It is typically found in a variety of habitats including open woodlands and scrub areas. This shrub reaches up to 3 meters (10 feet) in height and 2.5 meters (8 ...<|control11|><|separator|>
[96]
Philadelphus coronarius L. - World Flora Online
Native distribution. Introduced distribution. Found in. Asia-Temperate Caucasus North Caucasus; Transcaucasus; Western Asia Turkey. Introduced into. Asia- ...<|control11|><|separator|>
[97]
How to Grow and Care for Korean mock-orange - PictureThis
Native to woodland areas, korean mock-orange thrives in well-drained soil and partial shade, where it contributes to understorey diversity and attracts ...
[98]
Philadelphus schrenkii|Schrenk's tulip/RHS Gardening
A large, upright, deciduous shrub with peeling bark and very fragrant, white, four-petalled flowers, 3cm wide in clusters of five to seven.
[99]
https://www.rhs.org.uk/plants/12659/philadelphus-schrenkii/details
[100]
Mock orange (Philadelphus pekinensis) - PictureThis
Mock orange is a plant primarily native to regions of East Asia. Its natural range extends across temperate areas of the eastern Asian continent.
[101]
Philadelphus incanus Koehne | Plants of the World Online
The native range of this species is Central China (to Henan). It is a shrub and grows primarily in the temperate biome. Taxonomy · Images · General information.
[102]
Hybrid Philadelphus × lemoinei - iNaturalist
In 1884, Victor Lemoine crossed Philadelphus microphyllus with Philadelphus coronarius and produced this hybrid plant which he named P. lemoinei. The ...
[103]
https://www.inaturalist.org/taxa/Philadelphus_lemoinei
[104]
ISO-chromosomes and the origin of triploidy in hybrids between old ...
ISO-chromosomes and the origin of triploidy in hybrids between old and new world species ofPhiladelphus · 1. AllPhiladelphus species in nature are diploids 2n=26 ...
[105]
PHILADELPHUS 'Belle Étoile' - André Briant Jeunes Plants
Sterile triploid hybrid obtained by Lemoine (Nancy) in 1925, of medium size, with arched branches furnished with oval deciduous leaves, and bearing at the ...
[106]
https://andre-briant.fr/en/variety-range/access-to-varieties/deciduous-shrubs/4463-philadelphus-belle-etoile-.html