Flowering apricot variety (Prunus mume ‘Kobai’) blooming outside the Seattle Japanese Garden gatehouse in late January (Photo by Niall Dunne)
BY CORINNE KENNEDY
Prunus mume is an iconic flowering tree in the culture and gardens of Japan, where it is known as ume. Native to China, and known there as mei, it has long been cultivated in both countries—beloved for its delicate, very fragrant winter flowers and prized for the many culinary uses of its small, velvety yellow fruits.
It has a plethora of English common names, including Chinese plum, plum blossom, Japanese plum, Japanese flowering plum, Japanese flowering apricot, and flowering apricot. However, since the plant is neither a plum (botanically speaking) nor indigenous to Japan, one can alleviate the confusion by calling it “flowering apricot” or by sticking with the scientific nomenclature.
We’re fortunate that three Prunus mume ‘Kobai’ trees were planted five years ago on the eastern edge of the Seattle Japanese Garden’s entry courtyard. Even before the Garden re-opens each year in March, they delight Arboretum visitors with their very early, deep-pink blooms. What’s more, a young specimen of Prunus mume ‘Bungo’ was planted in early 2024 by the south wall of gatehouse and will add sweet-smelling, early-season white blossoms to the courtyard display.
Two of the three ‘Kobai’ trees blooming at the courtyard in winter. (Photo by Chie Iida)
Stunning Flowers and Useful Fruits
Prunus is a large genus that includes deciduous trees such as plums, cherries and peaches, as well as evergreen trees and shrubs, such as English laurel. Many of the deciduous plants in the genus have been bred either for their edible fruit or as ornamentals, but Prunus mume is cultivated for both beauty and culinary purposes. As an ornamental, its main season of interest is mid- to late-winter, when small, dainty, fragrant flowers open on the bare branches and persist in the cold weather for many weeks.
Prunus mume grows wild in the mountains of southwestern China, at elevations of 5,000 to 10,000 feet. In cultivation for thousands of years, it was first domesticated for its fruits, which are prized for their sour flavor, and was later cultivated as an ornamental. Over time, its beauty and cultural importance came to be celebrated in poetry, paintings, woodblock prints, textiles and ceramics. Once introduced into Japan, Korea, Taiwan and Vietnam, it naturalized on forested slopes and along streams. As in China, it was widely cultivated for its flowers and fruit, and celebrated in literature and the arts.
Prunus mume is one of several species (anywhere from three to ten, depending on your taxonomic source) in the apricot section of the genus, known as Prunus Section Armeniaca. This section is named after the apricot species Prunus armeniaca, native from Central Asia to Central China, whose large, fuzzy, and sweet edible fruits are the ones most commonly cultivated for consumption.
“Plum Park in Kameido,” a woodblock print by the Japanese artist Hiroshige (1797–1858) depicting Prunus mume in bloom. It was published in 1857 as the 13th print in the influential “One Hundred Famous Views of Edo” series. (Courtesy Rijksmuseum/Wikimedia Commons)
Prunus mume was introduced from Japan to Europe around 1844, and to North America in 1911. But, even today, it remains relatively uncommon here. Confusion around the common name of the plant may be partly to blame. For instance, the influential woodblock print depictions of flowering Prunus mume orchards by 19th-century Japanese artist Hiroshige—which inspired Van Gogh—were said to be of plums. And the most popular plum species in North America, Prunus salicina—native to China but long cultivated in Japan—also goes by the common name Japanese plum. Regardless, Prunus mume definitely deserves to be planted more in our gardens.
Traits and Growing Tips
A relatively small deciduous tree, Prunus mume grows between 20 to 30 feet tall when left unpruned. Mature trees have fine and complex branching; a dense, rounded habit; and gray or brownish flaking bark. Young branches, though, are green and smooth. The leaves are dark green, simple, sharply toothed, two-to-four inches long, and broadly ovate (egg shaped), with a wedge-shaped base and pointed tips. They open after flowering and sometimes develop yellowish fall color.
Small, fragrant, five-petaled flowers—held singly or in pairs on very short stalks—open in winter on the young, green branches. Though typically less than one inch across, they emit a powerful fragrance that’s both sweet and spicy. Colors range from white to deep pink, but trees in the wild typically produce single, white or blushed-pink blossoms.
Cultivars of Prunus mume abound (see below). Selections are available with single, semi-double and double flowers, and with colors ranging from white to pink and deep red. Depending upon latitude, elevation, and the weather, flowering begins from January to early April—and may begin even earlier in mild winters.
Ripe Prunus mume fruit at a Japanese market. (Photo courtesy Sakurai Midori/Wikimedia Commons)
The flowers are pollinated by insects, including bees, but the one- to one-and-a-half-inch fruits do not always develop. When formed, they are fuzzy-skinned and yellow in color (sometimes with a reddish blush), and they ripen in summer. Botanically, they are drupes—fleshy fruits with thin skins and a central stone that contains a single seed. Sour or bitter in flavor, they are typically not eaten fresh, even in Asian countries, but are processed with alcohol or salt—or by drying—to create popular foods and beverages. Fortunately, processing also inactivates enzymes that produce poisonous chemicals in the fresh fruit.
Prunus mume trees require winter dormancy, growing well in temperate regions with four-season climates. Hardy to USDA Zone 6 (minimum temperature at least -5 degrees Fahrenheit), they perform best when grown in deep, rich, acidic, well-drained soil and full sun. Well-grown and healthy trees are unlikely to develop significant problems, but potential pests and diseases include aphids, borers, tent caterpillars, bacterial canker and brown rot.
A Cultural Icon
Prunus mume has been an iconic tree through-out Japanese cultural history. It was planted in Japan’s early capitals, and its flowers, treasured by the aristocracy, were represented in literature and the arts. In haiku poetry, ume became a season word (kigo) for early spring. And during the Nara period (710–794 C.E.), several important families chose it to illustrate their crests (umemon). In both China and Japan, it was associated with good fortune, and included in the “three friends of winter” art motif, along with pine and bamboo, symbolizing steadfastness, perseverance and resilience. However, though greatly beloved in the Nara period, flower-ing apricot lost its position in the Heian period that followed (794–1185 C.E), when flowering cherries came to be more highly regarded.
In Japan, Prunus mume has traditionally been planted as a specimen tree, as well as in orchards, both ornamental and fruiting. It is used for bonsai, and its branches are used in flower arrangement (ikebana). It takes well to annual pruning, a traditional practice in Japan that’s used to create an attractive, picturesque habit and to promote flowering and fruiting. With gnarled trunks and branching, regularly pruned and very old trees are revered for their ancient appearance.
Botanical drawing of Prunus mume flowers, leaves, branches, and fruit, from Flora Japonica, 1870. (Image: Philipp Franz von Siebold and Joseph Gerhard Zuccarini/Wikimedia Commons)
When processed, ume fruits have long been an important part of the traditional Japanese diet. Products include salted and pickled plums (umeboshi); umeboshi plum vinegar, considered a health drink; sauces; flavorings for many foods, including crackers and candies; and “plum wine” (umeshu), a popular sweet/tart liqueur. (Again, the nomenclature is a bit baffling because the fruits are technically not plums.) In Japan, as well as China, medicinal uses have also been developed. Recent research has shown that the plant has multiple medicinal properties, including the ability to suppress cancer cells.
Cornucopia of Cultivars
Hundreds of cultivars have been created—at least 250 in Japan alone, where complex systems of classification have been developed to account for subtle variations in flower form, color and size. In the United States, beginning in the 1920s, the W. B. Clarke Nursery made many early introductions—both new selections and Japanese plants that were given English names. More recently, the late Dr. J.C. Raulston (of North Carolina State University’s J.C. Raulston Arboretum) was a learned and enthusiastic promoter of the species and its cultivars, contributing to their wider availability in recent years. (In his book “North American Landscape Trees,” published by Ten Speed Press in 1996, local expert Arthur Lee Jacobson describes more than 40 of these cultivars.)
Unfortunately, both the species and cultivars remain relatively uncommon in the U.S., includ-ing Seattle, and may be difficult to locate at retail nurseries. However, at least a few selections are readily available from online, mail-order nurseries. Some of the more well-known cultivars are ‘Fragrant Snow’ (a very early bloomer, with beautiful white, semi-double flowers), ‘Peggy Clarke’ (deep-rose-pink, double flowers), and ‘Matsubara Red’ (dark-red, double flowers). Weeping selections include ‘W.B. Clarke’ (pale-pink, double flowers) and ‘Pendula’ (soft-pink, single or semi-double flowers).
The cultivar on the east side of our Japanese Garden courtyard, Prunus mume ‘Kobai’, was developed in Japan but has been available in North America since at least 1991. A vigorous selection, it matures at about 25 feet tall and wide. Deep-pink flowers, borne profusely on the bare branches, are semi-double, with white stamens, and they emit a sweet, spicy fragrance, sometimes described as “cinnamon-like.” In the Pacific Northwest, flowering may begin in mild years as early as December, but more typically in February. Flowers are hardy to about 20 degrees Fahrenheit, but unopened buds will tolerate even colder temperatures. ‘Kobai’ often sets fruit, and its fall color is pale yellow. The specimens in the courtyard were somewhat mature when planted and have already reached about seven feet high.
‘Bungo’ was planted across the courtyard in March 2024 to commemorate the 100th anniversary of the Japan-America Society of the State of Washington. The Arboretum Foundation’s 2024 annual report said the “tree symbolizes the strong and resilient roots in our community, a commitment to building bridges for the next generation, and a continuing friendship between the United States and Japan.” The specimen was just three feet tall at planting time. The mature height will be around 15 feet. The cultivar’s long-lasting, fragrant white flowers display a very subtle pink blush. ‘Bungo’ is named for a historic province in Japan (modern-day Ōita Prefecture). It has been cultivated in Japan for hundreds of years for its larger, relatively sweeter fruit. Some scientists think it may actually be a hybrid of P. mume and P. armeniaca.
Garden staff and members of the Japan-America Society at the planting of Prunus mume ‘Bungo’ in early 2024, with ‘Kobai’ flowering in the background. (Photo courtesy JASSW)
Prunus mume is an excellent tree for small gardens and should be planted close to homes or near well-used walkways to ensure that its delicate winter blooms will be seen, even on cold and rainy days. I’m grateful that these four specimens are planted prominently outside the Japanese Garden, to be seen and appreciated by all who walk nearby in the dark months of late winter. ❦
Adapted from a post that first appeared on the Japanese Garden Blog, seattlejapanesegarden.org/blog.
Corinne Kennedy is a garden guide, frequent contributor to the Japanese Garden Blog, retired garden designer, and member of the “Arboretum Bulletin” Editorial Board.
Bibliography
Jacobson, A.L. “North American Landscape Trees.” Ten Speed Press: Berkeley, CA. 1996.
J. Raulston Arboretum. “Prunus mume: Flowering Apricot.” Online at jcra.ncsu.edu/horticulture/plant-profiles.
Moore, R. and Yoneda, K. “Prunus Mume: Rosaceae.” “Curtis’s Botanical Magazine.” August 2022. Published online at doi.org/10.1111/curt.12455.
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This article is reprinted from the winter 2025 issue of the Arboretum Bulletin, our quarterly botanical and horticultural magazine. Published since 1937, the Bulletin is a benefit of Arboretum Foundation membership and features in-depth articles on the Arboretum collections and history, as well as general information of interest to plant lovers in the Pacific Northwest and beyond. Join/subscribe today.
