Prunus serrulata
Few trees capture the imagination quite like the Japanese cherry, or Prunus serrulata, renowned globally for its breathtaking spring blossoms. But beneath its iconic beauty lies a fascinating botanical story of complex origins, ancient cultivation, and centuries of human artistry. This isn't just one tree species; it's a living tapestry woven from diverse wild cherries and meticulous horticultural skill, culminating in the dazzling varieties we cherish today. Japanese cherry trees are not a single species but a diverse group, many of which are complex hybrids cultivated over centuries. The Oshima cherry (Prunus speciosa) from Japan's Izu Oshima Island is a foundational ancestor for many popular ornamental varieties. Cultivars like 'Kanzan' exemplify the beauty and adaptability that have made Japanese cherries beloved worldwide for events like Hanami.
AI Summary
Few trees capture the imagination quite like the Japanese cherry, or Prunus serrulata, renowned globally for its breathtaking spring blossoms. But beneath its iconic beauty lies a fascinating botanical story of complex origins, ancient cultivation, and centuries of human artistry. This isn't just one tree species; it's a living tapestry woven from diverse wild cherries and meticulous horticultural skill, culminating in the dazzling varieties we cherish today.
- Japanese cherry trees are not a single species but a diverse group, many of which are complex hybrids cultivated over centuries.
- The Oshima cherry (Prunus speciosa) from Japan's Izu Oshima Island is a foundational ancestor for many popular ornamental varieties.
- Cultivars like 'Kanzan' exemplify the beauty and adaptability that have made Japanese cherries beloved worldwide for events like Hanami.
The Essence of Spring: Prunus Serrulata
The term Prunus serrulata refers to a species of cherry tree naturally found across Japan, China, Korea, and Vietnam. However, it's more commonly known for its spectacular ornamental cultivars—the very trees that paint the landscape pink and white each spring and have become a global symbol of renewal and fleeting beauty.
A Tree's Natural Profile
In its wild form, Prunus serrulata is a modest deciduous tree, typically growing 8 to 12 meters tall with a single trunk and a dense canopy. Its smooth, chestnut-brown bark is distinctive, often marked with prominent horizontal lenticels—those tiny pores that allow the tree to breathe.
Its leaves are quite elegant, arranged alternately along the branches, shaped like an elongated oval with finely serrated edges. As autumn arrives, these green leaves put on another spectacular show, transforming into brilliant shades of yellow, red, or crimson before falling.
The quintessential flowers emerge in spring, clustered in groups of two to five, often appearing just as the new leaves unfurl. In the wild, these blossoms are typically white to soft pink, each with five delicate petals—a simpler beauty compared to their cultivated cousins.
While famed for their flowers, these trees also produce a small, globose black fruit called a sakuranbo. Though similar to other cherries, sakuranbo are smaller and more bitter, making them generally unpalatable raw. They exist primarily to house the seed, not as a culinary delight, a testament to the tree's evolution for floral display over fruit production.
The Roots of Cultivation: The Oshima Cherry
A pivotal player in the story of ornamental cherry trees is Prunus speciosa, known as the Oshima cherry. This species, endemic to Japan—particularly Izu Oshima Island—is a direct ancestor for many of the beloved cultivars we see today. Its vigorous growth and beautiful flowers made it an ideal candidate for early cultivation.
As Japan's population grew, especially in the southern Kanto region during the Kamakura period, Oshima cherries were brought from Izu Oshima to Honshu, the main island. From there, their cultivation spread to Kyoto, the nation's capital, where their beauty could be appreciated more widely.
Centuries of Horticultural Artistry
The true explosion of cherry tree diversity began with deliberate cross-breeding. In the Muromachi period, Oshima cherries were hybridized with P. yamasakura, giving rise to early cultivars within the 'Sato-zakura Group,' such as 'Fugenzo' and 'Mikurumakaishi.' This marked the beginning of truly ornate, cultivated varieties.
The Edo period saw an even greater surge in horticultural innovation. Enthusiastic growers produced a vast array of double-flowered cultivars, planting them in grand daimyo gardens, along riverbanks, and within the grounds of Buddhist temples and Shinto shrines. Over 200 distinct cultivars were documented during this era, many still recognized today.
The Complex World of 'Sato-Zakura'
Modern DNA studies have revealed that many of the cherry blossom cultivars cherished globally for hanami—the Japanese tradition of flower viewing—are not simple species. Instead, they are intricate hybrids, born from the complex cross-pollination of the Oshima cherry with various wild species like P. sargentii, P. itosakura, and P. incisa.
This genetic complexity led to a refined classification. While some Western systems might group these cultivars under Prunus serrulata var. lannesiana or pendula, detailed genetic evidence places them more accurately into the 'Prunus Sato-zakura Group' or 'Cerasus Sato-zakura Group'—a classification that truly reflects their hybrid heritage.
'Kanzan': A Global Ambassador
Among the multitude of cultivars, 'Kanzan' stands out as perhaps the most popular Japanese cherry tree for hanami in Europe and North America. Also known as 'Sekiyama' or 'Kwanzan,' it boasts qualities that make it exceptionally well-suited for diverse climates and garden spaces.
'Kanzan' thrives even in colder regions, making it more adaptable than some other popular varieties like the 'Yoshino cherry.' Its compact size makes it ideal for gardens, and its large, deeply pink, double-petaled flowers offer a truly spectacular display. Imagine the streets of Bonn, Germany, lined with 300 'Kanzan' trees, a magnificent sight each spring.
The influence of 'Kanzan' extends further, as it has served as the parent for new cultivars developed in Western countries, such as 'Pink Perfection' and 'Royal Burgundy.' These offspring carry forward the beauty and resilience of their esteemed ancestor.
The Art of Propagation
Many of these highly cultivated varieties, particularly those with double flowers where stamens are replaced by extra petals, often lose their natural fertility. For example, cultivars like 'Fugenzo' and 'Ichiyo' have pistils that may transform into leaf-like structures, making them unable to produce viable seeds.
This means that to preserve these unique and beloved forms, human intervention is essential. Growers must rely on artificial propagation methods like grafting—attaching a cutting from the desired cherry onto the rootstock of another tree—or taking cuttings directly from the plant. In Europe and North America, Prunus avium is often used as the rootstock for these grafts.
Notable Sato-zakura Cultivars
The 'Sato-zakura Group' includes many magnificent varieties, each with its own unique charm.
Cultivar Alternative Names 'Kanzan' 'Sekiyama', 'Kwanzan' 'Choshu-hizakura' 'Kenrokuen-kumagai' 'Fugenzo' 'Shiro-fugen' 'Ichiyo' 'Hisakura' 'Shirotae' 'Mt. Fuji Cherry' 'Taihaku' 'Ukon' 'Grandiflora'
Article
Prunus serrulata
Prunus serrulata or Japanese cherry is a species of cherry tree that grows wild in Japan, China, Korea and Vietnam. The term also refers to a cultivar produced from Prunus speciosa (Oshima cherry), a cherry tree endemic in Japan. Historically, the Japanese have developed many cultivars by selective breeding of cherry trees, which are produced by the complicated crossing of several wild species, and they are used for ornamental purposes all over the world. Of these, the cultivars produced by complex interspecific hybrids based on the Oshima cherry are also known as the Cerasus Sato-zakura Group.
Varieties and form
Classification
The classification of cherry blossoms varies from country to country and from period to period. For example, in the Japanese classification, P. serrulata Lindl. f. albida, P. serrulata var. spontanea, P. serrulata var. pubescens and P. serrulata Lindl. var. sachalinensis, the varieties and form constituting this species, are classified as independent species because of their genetic, morphological, and flowering time differences.
There are several varieties and form (or species):
• Prunus serrulata f. albida (syn. Prunus speciosa). Japan. • Prunus serrulata var. spontanea or Prunus serrulata f. spontanea (syn. Prunus yamasakura). Japan.
Some books say that P. yamasakura grows wild in China and Korea, but P. leveilleana and P. sargentii were mistaken for P. yamasakura.
• Prunus serrulata var. pubescens (syn. Prunus leveilleana). Japan, Korea, China. • Prunus serrulata var. sachalinensis (syn. Prunus sargentii). Japan, Korea, eastern Russia, China.
Trees and flowers
Prunus serrulata is a small deciduous tree with a short single trunk, with a dense crown reaching a height of 7.9–11.9 metres (26–39 ft). The smooth bark is chestnut-brown, with prominent horizontal lenticels. The leaves are arranged alternately, simple, ovate-lanceolate, 5–13 cm long and 2.5–6.5 cm broad, with a short petiole and a serrate or doubly serrate margin. At the end of autumn, the green leaves turn yellow, red or crimson.
The flowers are produced in clusters of two to five together at nodes on short spurs in spring at the same time as the new leaves appear; they are white to pink, with five petals in the wild type tree. Its fruit, the sakuranbo, has differences from the Prunus avium in that sakuranbo are smaller in size and more bitter in taste; the sakuranbo is a globose black drupe 8–10 mm in diameter. Owing to their bitter taste, the raw sakuranbo is unpalatable and rarely eaten; instead, the seed inside is removed and the fleshy part preserved.
Because of its evolution, the fruit developed merely as a small, ovoid cherry-like fruit, but it doesn't develop past a small amount of fleshy mass around the seed; as P. serrulata was bred for its flowers, its fruits do not enlarge the way cherry varieties bred for their fruit do.
Cultivars
Prunus serrulata
Among the Prunus serrulata, many cultivars derived from Japanese endemic Prunus speciosa (Oshima cherry), are widely grown as a flowering ornamental tree, both in Japan and throughout the temperate regions of the world. Numerous cultivars have been selected, many of them with double flowers with the stamens replaced by additional petals. According to an unprecedented and detailed DNA study conducted by the Forestry and Forest Products Research Institute in 2014, many of the cherry blossom cultivars used for hanami around the world were derived from the complicated hybridization of wild species such as P. sargentii, P. itosakura, P. leveilleana, P. apetala, P. incisa and P. campanulata with the Oshima cherry, an endemic species of Japan.
As the population increased in the southern Kanto region during the Kamakura period, Oshima cherries, which were originally from Izu Oshima Island, were brought into Honshu (the main island of Japan) to be cultivated and brought to Kyoto, the capital of Japan. In the Muromachi period, Oshima cherries were crossed with P. yamasakura, and cultivars of Sato-zakura group such as 'Fugenzo' and 'Mikurumakaishi' began to appear. In the Edo period, various double-flowered cultivars were produced and planted on the banks of rivers, on Buddhist temples, in Shinto shrines and in daimyo gardens in urban areas such as Edo, and the common people living in urban areas could enjoy them. In the documents at that time, more than 200 cultivars of cherry trees were recorded, and currently known cultivars of cherry trees such as 'Kanzan' are also mentioned.
In American classification, these cultivars are classified as Prunus serrulata var. lannesiana or Prunus serrulata var. pendula (syn. Prunus lannesiana). However, detailed DNA studies revealed that they were complex interspecific hybrids with the Oshima cherry, so they are classified as the Prunus Sato-zakura group or Cerasus Sato-zakura group.
'Kanzan' is the most popular Japanese cherry tree cultivar for cherry blossom viewing in Europe and North America. Compared with 'Yoshino cherry', a representative Japanese cultivar, it is popular because it grows well even in cold regions, is small and easy to plant in the garden, and has large flowers and deep pink petals. In the city of Bonn, Germany, there is a row of cherry trees where 300 kanzan trees were planted in the late 1980s. In Western countries, 'Pink Perfection' and 'Royal Burgundy' originated in 'Kanzan' have been created.
In some cultivars, the pistil changes like a leaf and loses its fertility, and for example, 'Fugenzo' and 'Ichiyo', can only be propagated by artificial methods such as grafting and cutting.
In cultivation in Europe and North America, it is usually grafted on to Prunus avium roots; the cultivated forms rarely bear fruit. It is viewed as part of the Japanese custom of Hanami.
Some important cultivars include:
• 'Kanzan'. = 'Sekiyama' or 'Kwanzan'. Cerasus Sato-zakura Group 'Sekiyama' Koidz
'Choshu-hizakura'
• 'Choshu-hizakura' Also known as 'Kenrokuen-kumagai'. Crasus Sato-zakura Group 'Choshu-hizakura'
• 'Fugenzo'. = 'Shiro-fugen'. Cerasus Sato-zakura Group 'Albo-rosea' Makino
• 'Ichiyo'. Cerasus Sato-zakura Group 'Hisakura' Koehne
• 'Shirotae'. Mt. Fuji Cherry. Crasus Sato-zakura Group 'Shirotae' Koidz
• 'Taihaku'. Cerasus Sato-zakura Group 'Taihaku' Ingram
• 'Ukon'. = 'Grandiflora', P. serrulata f. grandiflora Wagner. Cerasus Sato-zakura Group 'Grandiflora' A. Wagner
Gallery
Prunus serrulata
• P. serrulata flowers • Bark showing lenticels • Leaf close up • Kurozome, the tree spirit of the Japanese Cherry Tree • Cultivar flower close up • Prunus serrulata – Cherry blossoms • Leaves in autumn • Typical autumn foliage • 'Ukon' (Prunus lannesiana Wilson cv. 'Grandiflora')