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Semi-double Prunus ‘Ohara-nagisa-zakura’ is a recently imported cherry with a habit suitable for naturalistic planting schemes
Developments in Japanese flowering cherries
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hen the full crown of a Japanese flowering cherry is in bloom it is a most spectacular garden plant. They are traditionally planted as ornamental specimen trees, usually sited so that an individual can be appreciated from all sides as a showy and exotic thing. Most of the new introductions discussed below are suitable as specimen trees. But in the wild, cherries are typically found in sunny spots in forests or at the forest edge. Therefore, it is useful to remember
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Most flowering cherries in gardens are cultivars from the 19th and early 20th century. Wybe Kuitert reports on more recent cultivars that are being trialled in the Netherlands.
that many cherries can perform perfectly in less formal design schemes. Two showy, naturalistic cultivars suitable for this style are discussed below (‘Kongo--zan’ and ‘Ohara-nagisa-zakura’). Other, recently discovered cultivars must have futures as road-side trees (‘Yae-edo-higan’ particularly, but also ‘Beni-yutaka’). They are ideal for avenue planting on wide verges. Finally, there is a cultivar (‘Sumaurafugenzo-’) with more convincing yellow flowers than any previous cultivar. March 2016
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limbs. These will eventually support a wide crown of 10m or more in diameter. The open shape is shown to its best advantage when planted as a solitary tree on a wide lawn. It prefers an open soil structure, preferably on an undulating slope. The rather thick young twigs have beige bark. The leaves are pale brownish green on emergence and are serrated with long awns (hair-like tips to each serration). Mature leaves are large and resemble the leaves of Prunus serrulata var. speciosa (Oshima cherry). The flowering shoots bear a sprout of foliage at the tip and the flowers are in corymbs of four to five. The stalk of the corymb is longer when the weather is cold and spring is slow to come. In bud the petals are pale pink between the serrated sepals. These open to white, flat flowers 5cm in diameter. The five petals are round or ovate, with a notch at the tip, and about 2cm in diameter. It blossoms at the end of March in the trial collections and a few small, black cherries develop in June. ‘Amagi-yoshino’ was found in 1957 by research botanist Yo- Takenaka (1903–1966) among hybrids from his experiments in search of the parents of ‘Somei-yoshino’. He named it after Mount Amagi where hybridiz ation between P. serrulata var. speciosa (seed parent of ‘Amagi-yoshino’) and P. pendula f. ascendens (edo-higan cherry, pollen parent of ‘Amagiyoshino’) occurs frequently in the wild.
Prunus ‘Amagi-yoshino’
All cherries discussed on these pages are in the trial collections of Noriko Kuitert and Wybe Kuitert in the Arboretum Belmonte in Wageningen, and Keukenhof garden in Lisse, both in the Netherlands. These trial collections were set up in 1997.
‘Amagi-yoshino’ This cherry is recommended because of its healthy growth, sturdy stature when mature, and its early and profuse blooming with large flowers. Young trees put up a strong leader that soon produces a few side branches that develop into heavy Prunus ‘Beni-gasa’
All photographs by Wybe Kuitert
March 2016
‘Beni-gasa’ This cherry is a recommended for its classic beauty, as its large ‘powderpuff’ flowers remind me of the glamorous days of Japonism a century ago, when such puffy blossom was the standard in cherry beauty. It is not a strong grower and needs a healthy, open soil, lots of water and plenty of sunshine in the growing season. It benefits from ➤ 29
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an application of durable, light compost just before the flowers open, which will aid it through the growing season until June and July. Farmyard manure at the end of autumn will also encourage root growth in the mild days of winter. This cultivar will make a tree of about 5m in height with an open, spreading crown. The flowers appear at the same time as the first, pale brownish green leaves, both forming part of the beauty of this cherry in its prime. In mid spring the pale pink of the fully opened flowers, hanging in gaudy bunches, contrasts with the dark pink of the developing buds. Closer inspection shows that the developing flowers are darker on the outside and paler in the centre. The fully opened flowers are 5–6cm in diameter and have about 40 petals. The mature leaves are coarsely serrated and no fruit is produced. This cultivar was selected in 1963 from natural hybrids between ‘Itokukuri’ and other garden flowering cherries, which suggests that ‘Itokukuri’ was the seed parent. The name translates as ‘red umbrella’. The breeder was Masatoshi Asari (born 1931), a cherry lover and high school teacher in Matsumae, Hokkaido. He raised many doubleflowered cherries by sowing the occasional fruits that he could find on existing double-flowered cultivars. ‘Beni-yutaka’ This cultivar is already relatively well-known in Europe. It is a fastgrowing tree with an attractive, vase-shaped crown, similar to ‘Kanzan’ in its younger years. As it matures its crown is not as spreading as that of ‘Kanzan’, making it more suitable for roadside planting. Its main attraction is its profuse, semidouble, pink flowers. 30
Growing to a height of 12m or more, it produces several ascending leader branches which spread as it ages. The flowers, to 5cm in diameter with about 15 petals, are borne in clusters of around five. The petals have a thick texture, as in P. sargentii, and are deeper pink on the outside of the flower, and show deeper coloured veins as they age. Dark, greenish red foliage emerges during flowering. This cultivar was raised in 1961 and introduced by Asari, who cited P. serrulata ‘Ryu-un-in-beniyae’ as one of its parents. This parent cherry grows at Ryu-un-in temple in Matsumae and is semi-double with remarkably cupped petals, and seems to be derived from P. sargentii. It
therefore gives the autumn colour of this species to ‘Beni-yutaka’, and the name means ‘abundance of red’. Beware that the same cultivar name has been used for a sweet, edible cherry, as well as for a strawberry and sweet potato. ‘Ko- -ka’ This cherry is recommended for its regular crown shape with balanced branches on all sides. It is attractive in bud and provides a gorgeous display of flowers. It makes a tree of 5m or more in height, with multiple side branches set on a low stem. It makes a good replacement for ‘Kanzan’ in situations that require a smaller and neater tree shape. The bright red, jewel-like buds are
Prunus ‘Beni-yutaka’
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– (right) comes into flower (left), and its regular Different shades of pink are revealed as Prunus ‘Ko-ka’ crown shape with a short stem is evident from an early age (right)
borne in abundant bunches and the flowers in various stages of unfolding show various shades of pink, giving a beautiful show. The large flowers come in clusters of three or four and have 30–40 petals each, the petals in the centre of each flower being somewhat spiraling. A small amount of pale bronze-green foliage emerges at the same time as the blossom. The flowering season is long, perhaps a little longer than that of ‘Kanzan’. It has good autumn colour of yellow
and bright red. It was released by Asari in 1965, who cited P. sargentii as a parent. ‘Ko--ka’ means ‘showy, deep red’ and it is sometimes listed as ‘Kouka’. ‘Kongo- -zan’ This cherry is recommended because of its healthy constitution and abundant pale pink blossom borne on cascading branches. Although its growth is erect, the stem will not be straight unless you stake it. Side – Prunus ‘Kongo-zan’
branches are ascending, forming a mid-sized, erect tree to 10m in height at the most, on good soil. Each branch starts to bloom from the inside of the tree out, so flowers at the ends of the branches are the last to open. This gives a pink fringe to the blossom clouds on each branch. The flowers are in stalked clusters of about four flowers, often with one flower halfway along the peduncle. The flowers open flat, are about 4cm in diameter, and have five petals. The petals are circular or ovate, with a notch, and are pale pink. The odd flower has one or two extra, stalked petals. It flowers in mid April for about two weeks in north-west Europe, and bears black, spherical cherries, about 1cm in diameter, in July. The foliage starts emerging at flowering time and is yellowish brown, suggesting, together with the circular and rather thick petals, P. sargentii blood. The bark of the thick, young twigs is beige. The leaves have glaucous undersides and their serration is rather regular and single, without awns. Some leaves are orbicular or ovate, without an elongated tip. Summer foliage is healthy and rarely attacked by caterpillars or aphids. In gardens it will look best in more informal settings, such as mixed with other trees and shrubs bordering a wide lawn. This cultivar is not modern, but it is only just making inroads into Europe. It was noted in the famous Arakawa collection in Tokyo a century ago. The name refers to Mount Kongo- in Nara, Japan, which has a history of mountain asceticism. Do not confuse it with ‘Kongo-zakura’. ‘O hara-nagisa-zakura’ This is another cherry suitable for more naturalistic planting styles. It has upright growth with rather ➤ 31
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heavy, ascending side branches. This results in a height of about 10m at most. The pink, semi-double flowers contrast beautifully with the dark red, emerging leaves. In flower it attracts many bees. It is similar in many ways to P. serrulata var. spontanea (Japanese mountain cherry). The cup-shaped flowers, about 4cm in diameter and with 15 loose petals, are borne in corymbs of about five. They are deep pink in bud and, on opening, the inner petals quickly turn white, whereas the outer petals remain pink for a couple of days before turning white. The flowers have a faint fragrance, are borne in mid April, and are followed by abundant fruit. The young leaves are dark red with a green mid-rib and emerge at the same time as the flowers. Mature leaves have regular, fine, single serrations with a bright red petiole. The autumn show of colour starts with a few deep orange leaves mixed in a mosaic of green leaves, and eventually all the leaves turn a deep orange. I received this cultivar from Kyoto Botanical Garden. Its origin was a bit of a mystery as Ōhara Nagisa seems, at first sight, to be a woman’s name, although personal names are hardly ever given to cherries in Japan. Recently, though, it has been confirmed that it came from the Jakkō-in temple in the village of Ōhara, north of Kyoto, where it grows as ‘Ōhara-migiwa-zakura’. ‘Nagisa’ means waterside or beach, and could refer to the wavy flowers, pink and white mixed together, hanging shower-like from the branches, or looking like waves washing ashore. ‘Orihime’ This cultivar originated as a seedling of ‘Amanogawa’; it has the same healthy growth and is similar in its 32
fastigiate habit. The main difference is the wider bend at the point where the branches attach to the main stem. This guarantees a longer life for the tree, as it avoids the problem that older ‘Amanogawa’ have of developing wounds where the upright branches are so tightly packed that the bark cannot develop properly. The flowers of ‘Orihime’ are less pink, with a more creamy white than ‘Amanogawa’, but just as gorgeous. I received it from the raiser, Benoît Choteau of Binche, Belgium, in whose nursery it grew as a seedling of ‘Amanogawa’ in 1999. My wife, Noriko Kuitert, named it ‘Orihime’ a weaving princess in the East Asian legend of Amanogawa, the Milky Way, where Orihime is represented by the star Vega. ‘Sumaura-fugenzo-’ This cherry is sensational because of its yellowish white and sturdy, healthy growth. Apart from its peculiar colour it is exactly the same as ‘Fugenzo-’, from which it is a sport. It makes a spreading tree with a flattened crown. On a favourable soil specimens may reach 15m in height. The young leaves are coppery red (RHS Colour Chart 166B) at flowering time, quickly turning to bronze-green (152A) and becoming well-developed among the flowers. Among the mature leaves you can sometimes find a few that lack the usual acuminate tip. The colour of the double flowers is a most striking yellowish white (150D, or even 150C). The flowers are borne about five per hanging corymb, and are up to 5cm in diameter. Each flower has about 30 petals and two leaf-like, deformed, infertile pistils in the centre. It is one of the latest flowering cherries, blooming just a little later than ‘Kanzan’. This cultivar was discovered in
Prunus ‘Orihime’ Prunus Ōhara-nagisa-zakura’
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– Prunus ‘Sumaura-fugenzo’
1990 as a sporting side branch on a tree of ‘Fugenzo-’ in Suma-ura Park in Kobe. A similar sport has been found elsewhere in Japan, but it is the one from Suma-ura that has been taken into cultivation. ‘Yae-edo-higan’ The straight and upright tree shape of this double-flowered cultivar is notable. The plant is clearly a selection of P. pendula f. ascendens (Japanese spring cherry), that is longlived in favourable conditions, with some spectacular and monumental trees in northern Japan thought to be 1,000 years old or more. Reaching a height of about 15m, it makes a good roadside tree in wider verges, or for other landscapes that require erect, straight trees. The double flowers, about 4cm in diameter, resemble a rose, consisting of 20–30 white, wavy petals. The flowers are borne on long stalks, with about three per cluster, at the end of April. The willow-like, young leaves emerge at the same time. The thick, tubular calyx and short sepals are noticable features. Although this cultivar is not as floriferous as, for example, ‘Kanzan’, March 2016
it is expected that, as trees age, the blossom will become more abundant – a phenomenon observed in the wild with P. pendula f. ascendens. I received my specimen from Kyoto Botanical Garden which had no information on its provenance. The name translates as ‘double spring equinox cherry from Edo’, the old name for Tokyo. It does not originate from this city, but that is a name used in western Japan to denote cherries from the east, beyond Edo. ‘Yo-ko-’ Most of the famous cherry tourist spots in Japan are planted with P. yedoensis. But among these trees you might notice another of more recent origin that flowers a few days earlier, and is perhaps even more spectacular because of the deep pink of its blossom. That cherry is ‘Yo-ko-’. It seems to have a promising future in the face of climate change and rising spring temperatures, which are giving P. yedoensis a hard time in Japan. The latter is also becoming more affected by witch’s broom. This cultivar has ascending branches and healthy growth,
reaching 8m in height. The blossom sits on branches that are pendulous at the tips, giving a most effective flower show. There are about three, hanging flowers per cluster. The single flowers are deep pink, 4.5cm in diameter, and the petals typically have tiny wrinkles. The mature leaves are shiny green on the upper surface and not shiny on the back where there are fine hairs on the veins. In Japan it produces enough nectar to attract many small birds to drink it. In northern Europe it is perhaps only the early bumble bees that are attracted to its flowers. However, as in Japan, it remains a useful option as our spring weather becomes less predictable. This cultivar is a hybrid between P. campanulata, from which it gets its deep pink colour and abundant nectar, and ‘Amagi-yoshino’ described above. It was raised by Takaoka Masaaki (1909–2001) and registered in 1981, after which it became widely planted. The name translates as ‘bright rays of spring sunshine’ and it is sometimes listed as ‘Yoko-zakura’. Conclusion After many years of research and observation, the cherries I have presented here are a first selection from about 120 barely known cultivars derived from Japanese and other east Asian Prunus. All are grown in the scientific collections at Arboretum Belmonte and Keukenhof garden, and readers are warmly invited to come and see them all. Wybe Kuitert is a designer, writer, landscape architect and university professor passionate about the cultivation, botany and cultural history of flowering cherries. He is the author of Japanese Flowering Cherries (Timber Press, 1999) 33