Quarryhill Botanical Garden

Advancing the Conservation, Study, and Cultivation of the Flora of Asia

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Featured Plants

View Archive Featured Plants of Quarryhill

Originally discovered by Swedish naturalist and plant hunter Carl Peter Thunberg, this shrub or small tree in the family Lamiaceae is native to China, Japan and Korea. It is notable for it's clouds of small jasmine-like tubular white flowers which form in late summer and fall - providing garden color when many other flowering plants have finished - these trees are stunning where they are planted in Quarryhill. Bright blue berries surrounded by red calyxes follow bloom. As a small tree it may reach 20 feet tall by 10-12 feet across.

Harlequin glorybower is it's normally used common name, but it is sometimes called peanut butter tree due to a singular aroma which emanates from the leaves when bruised. Clerodendrum derives from the Greek words klero (fate) and dendron (tree), giving rise also to the infrequently used common name fate tree.

Collected originally in the wild for Quarryhill in 1989 by McNamara, Maunder and Tsukie on Honshu, Japan at 1020 meters elevation.


(QBG #1994.296)


Collected as seed by the Shanghai Botanic Garden in 1992 at 600 meters elevation from a broadleaf evergreen forest in a mountainous region of Western Zhejiang Province, China.  Quarryhill received this plant in 1993 as a gift from John Domzalski, propagator and greenhouse director at the U.C. Berkeley Botanical Garden.
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This deciduous tree has evolved highly unusual leaves, each with a 2-lobed, truncate apex and 2 broad side lobes.  Flowers, in May, are cupular (cup-like) with 9 green tepals, the outer 3 sepal-like, curved and outwardly pendulous, the inner 6 petal-like, erect and with yellow striations.  Fruits are 6mm, samaroid (winged) nutlets, appearing in September & October.

Recent taxonomic changes based on DNA analysis now place this species in the only other genus besides Magnolia to occupy the Magnoliaceae family.  L. chinense and the Eastern North American species L. tulipifera represent an evolutionary phenomenon known as species disjunction.  In such cases, similar selection pressures, acting over eons of time, produce two very similar species, often derived from a common ancestor, that have physically drifted apart due to geological/continental separation.  This species is rare and endangered, occurring in small populations or as scattered individuals.  It requires regular water and full sun, and prefers rich, deep soil.








The Japanese Flowering Quince is truly sensational: a visual wonder with branches wreathed in spring color and pungently aromatic in the fall, its spicy fruit well-suited for jams and conserves.  It is native to sunny locations on hills and mountains in warm to cool temperate zones on the Japanese islands of Honshu and Kyushu. 

A dense, low deciduous shrub with both ascending and sprawling, spiny, well-branched stems, 30-100 cm in height, and wider spread.  Leaves are alternate, serrated, and ovate to obovate in shape, 2-5 cm long, falling unusually early amidst the growing season.  Flower appear in clusters, concurrently with new leaves, in April and May, are hermaphroditic or staminate (male), and measure 2.5-3 cm across.  Cupped, spreading petals are orbicular to widely obovate in shape with rounded apices.  Pome fruits are very fragrant, globose and glabrous (smooth surfaced), yellow to greenish yellow and 3-4 cm in diameter.  Their pulp is rather hard, of a whitish-yellow color and quite acidic.  The ovoid, mucilaginous seeds are dark brown.

Relatively easy to grow, Japanese Flowering Quince is happy in full sun to part shade, enduring most well-drained, friable soils, and accepting considerable pruning directly after flowering.



This deciduous tree is most notable for its shiny, brownish-orange to red colored bark which exfoliates in papery flakes.  It can reach 30 meters in the wild and has glabrous, reddish brown branchlets with resinous glands.  The deep green, glossy leaves are simple, alternate and doubly serrated, providing a vivid color contrast to the bark.  Inflorescences appear in May and June as 1-3 grouped racemes, followed by small (2-3 mm), ovate, winged nutlets on fruiting “cones”, 3-4 cm long, in July and August.

The Chinese Red Birch is well known for it’s bark, “...shining like burnished copper [that when peeled away] leaves behind it a creamy, glaucous bloom...” (Rogers, 1928).  It is native to north central China.

Culture is best in very well-drained soils with regular water, under full sun.  Bronze birch borer, leaf miners and aphids can be problematic in some areas and at certain times of year.  Prune when dormant (late January in mild-winter, non-freezing areas) to avoid sap bleed and pest introduction.  Also, avoid lawn plantings as all birches are greedy for water and nutrients.





This deciduous shrub is endemic to forests of Japan's Honshu Island, in the north and along its Japan Sea (northwestern) side. Its common name in Japanese, Hirohagomagi, refers to the sesame seed smell that exudes from the leaves when crushed.  Its leaves are a rich, dark green color, with hairy undersides and vivid, almost straight, lateral veins.  Striking, terminal panicles of creamy-white flowers, in a depressed pyramidal shape, appear from late April to mid-June, practically covering the plant.  Sensational, turgid drupes of brilliant scarlet-red, in broad, splayed clusters sporting beautiful red stems, appear from late July to October, gradually turning to bluish-black.  The fruit is 8-10 mm long by 5-7 mm wide, elliptically shaped, annd with a longitudinal groove extending along the ventral side. This shrub likes full sun to part shade, regular water, and a moist, rich, loamy soil. 


Siebold's Crabapple is a beautiful tree in every season.  It's modest size, 2-6 meters in the wild, and lovely show of flowers and fruit in spring and autumn respectively, make this a tree with many landscape design applications.  This example was grown from seed collected from the wild by Charles Howick, William McNamara, and Roger Warner on October 3, 1987 at c 210 meters elevation, from a large spreading bush growing on volcanic silt in a flat, open valley bottom with maple, ash, alder on the north side of Mt. Apoi in Hokkaido, Japan. 

This deciduous shrub has simple, serrate leaves, ovate to elliptical in shape, and often 3-lobed, rarely 5-lobed on young branches.  The 2-3 cm wide flowers, in groups of 4-8, are born in 4-6 cm wide corymbs that appear on the apices of young branches in April - June.  Red to brownish yellow pome fruits are somewhat globose in shape and 6-8 cm in diameter, appearing August - October.  It is native to China, Japan, and Korea. They thrive in full sun with moderate to regular water and must

Ideally, crabapples require plenty of over-winter cold for greater productivity (estimated as a minimum of 600 hours below 7° C).  They thrive in full sun with moderate to regular water and must be protected from typical rose family diseases (such as fireblight and mildews) and pests (such as scale, aphids, and apple moths) Prune only to define structure and remove suckers.  




The Igiri tree, as it is known in Japan, is dioecious (separate male and female individuals), reaching 8 - 21 meters in height with deep green, coarsely serrated leaves on red-tinged petioles.  Yellow-green flowers appear in April and May (or later, in cultivation) on panicles, 20-30 cm in length, with male (staminate) flowers slightly larger than female (pistillate) flowers.  Stunning berries follow in October and November, turning from purple-red to orange-red, 8-10 mm, adorning the female trees in clusters resembling loose bunches of grapes, drying to black with age.  The Igiri tree naturally occurs in deciduous broad-leaved and mixed forests at 400-3000 meters in elevation in China, Japan, and Korea, and is popular as an ornamental.  Cultural requirements for this species include full sun to part shade, with regular water in moderately fertile, well-drained soil.



Collected as seed at 1250 meters in Sichuan, China on October 7, 1996 by Mark Flanagan, Charles Howick, Tony Kirkham, and William McNamara.  Numerous blooms cover this rose from March through July with 5-petaled, slightly fragrant, pink to rose-purple/ red single flowers.  Even more impressive is the subsequent show of large, globose hips from which it gets its common name, the Chestnut rose.  Hips adorn the bush from August through October, deep yellow in color when mature and covered with large, decorative prickles.  This rose grows 1-2.5 meters in height with arching canes that bear leaves with 9-15 small, graceful leaflets.  It is native to a wide area of central and southern China as well as Japan, and is used medicinally, both for its roots and fruits.  Its hips are edible with a sweet & sour taste, and are also used in a fermented wine. 





Though considered an invasive weed in parts of the eastern United States, Rosa rugosa in its native coastal Asian habitat is endangered due to overdevelopment. It found favor in Britain near the end of the 19th century for its ease of cultivation, relatively long bloom period, hardiness and (bucking the current trend) its single flowers.  Long cultivated in Asia (since 1100, by some accounts), many commercial varieties originated in Japan.

With the common name Ramanas Rose or Sea Tomato, Rosa rugosa is very vigorous and hardy, and is resistant to wind, salt spray, arid conditions and most diseases.  It is often used in hedges and for erosion control.  Regular water and full sun are optimal for culture.  The hips are edible and can be used in preserves.

This deciduous, erect, multi-branching shrub reaches a height of 2 meters in the wild.  Branches are tomentose (closely covered with down or matted hair) with flat, slender, needle-like spines or prickles and glandular bristles.  The glossy, bright green, compound leaves are 5-13 cm long with 5-9 acutely serrated leaflets, each 2-5 cm long and with a rough, rugose (wrinkled or ridged) upper surface due to the reticulate (netted) venation on the underside.  Fragrant flowers, 6-7 cm in diameter, occur in groups of 1-3 on branch terminals with obovate petals of deep reddish-pink to pink to white, May through July.  Yellowish-red to dark red, smooth, succulent hips are compressed-globose in shape, 2-2.5 cm in diameter, and appear August to September.  This rose is native to coastal and sandy-soiled seaside locations below 100 meters elevation in China, Japan, Korea and Russia.




Known as the China Rose this plant, along with Rosa odorata var. gigantea, is a parent to many modern roses.  It occurs only in remote locations of Sichuan Province, and is threatened by habitat loss.  Flower color ranges from pure white to deep scarlet with many variations in between.  Blossoms appear in early March and last through April.


In combination with Rosa chinensis var. spontanea, also widely featured at Quarryhill, this stunning showpiece represents the ancient parentage of most modern day nursery roses so commonly found throughout the world, including Teas, Hybrid Teas, Polyanthas, Floribundas and Portlands, among many others.  As typical of the genus, it prefers regular water and full sun, and requires plenty of space or an ample structure on which to ascend.

Collected as open-pollinated seed in 2001 at the garden of Viru Viraraghavan, from a wild-origin parent collected as seed by Viru and Girija Viraraghavan in January, 1990 at 2,130 meters elevation from a climber, 10 meters tall, growing among tall deciduous trees under full sun, in an open scrub jungle on Mt. Sirohi, Manipur State, NE India.

This scrambler/climber has pinnately compound leaves, 5-10 cm in length, each with 5-9 leaflets, 2-7 cm long.  Its pure white flowers are solitary and simple, and, as implied by its name, very fragrant and unusually large in size, reaching a width of 10 cm.  It is evergreen to semi-evergreen, depending on climate, and is native to mixed forests, thickets and scrub on hillsides, pastures, grassy slopes and roadsides, at 1400-2700 meters elevation in the Yunnan province of China, Myanmar, N. Thailand and N. Vietnam.



Commonly known as evergreen wisteria, this particular plant was collected in 1991 at the base of Erlang Shan (Mountain), Sichuan, China.  Occurs in China, Laos, and Vietnam.  Long blooming period beginning in July through August.  Unlike wisteria this flower's clusters are upright.  Grows in full sun.  Requires a structure to climb on.


Among the rarest and most endangered of all maples, Acer pentaphyllum has been all but decimated in its native habitat, the mixed forests and valleys of southwest Sichuan, due to grazing and overdevelopment.  It is moderately tender, requiring protection from hard frosts and inappropriate for severe winter climates, requires regular water, and prefers full sun exposure.  This maple is notoriously difficult to propagate by seed (though grafting has been quite successful), with much fruit being parthenocarpic (produced without fertilization).  Quarryhill, however, has managed to germinate more than 200 seedlings over the past several years, the vast majority of which are now in an established conservation grove at Quarryhill where they are destined to provide seed stocks for future preservation of the species and reintroduction into its native Chinese habitats.  Through Quarryhill’s efforts, Acer pentaphyllum has become a symbol of the nascent struggle to address species loss in one of the world’s most compromised and ecologically threatened regions of the world.



As one of the largest deciduous trees in Japan and China, it was once considered endemic there until found by E. H. Wilson in China in 1910.  Autumn color is quite variable, from yellow to orange to red to mauve, and either wet or, especially, autumn conditions promote an elusive but potent foliar fragrance described as burnt or brown sugar, or vanilla.

The Katsura tree, as it is commonly known, requires ample water during the growing season and full sun, it is a broadly pyramidal, dioecious (each plant either male- or female-flowered) tree reaches a height of 30 meters in the wild, with a spirally twisting, peely trunk that develops longitudinal fissures and is often branched at the base.  Leaves are opposite or rarely alternate, on long branchlets, violet-red colored when young, and dimorphic (assuming two growth forms).  Leaf blades are up to 8 cm in length, slightly less in width, and are ovate to obovate to reniform (kidney shaped; the genus name refers to the Cercis or redbud leaf shape).  Staminate (male) flowers are pink and narrowly oblong and pistillate (female) flowers are single carpels), brown to blackish purple and 10-18 mm long, containing brown, winged seeds, 5 - 6.5 mm, appearing August - September.  Native to forest streamsides in China and Japan.