Primula sieboldii

Primula sieboldii wild species planted in a garden

Family: Primulaceae Japanese name: SAKURASOO
English name: Siebold primrose or Japanese primrose
Plant type: deciduous in winter Habitat: damp areas of riversides
Blooming season: Aril-May Height: 15-40cm

A honorable Japanese poet, ISSA KOBAYASHI, admired the
flowers of Primula sieboldii and made the following HAIKU
(Japanese short poem):

(Even grasses have cherry blossom flowers in Japan, the country
of cherry blossoms)

Primula sieboldii is called SAKURASOO (= cherry blossom plant)
in Japanese since its flowers resemble cherry blossoms. This
species has a cultivation history of more than 300 years. There
were large areas of this plant in UKIMAGAHARA and
TODAGAHARA, suburbs of Edo (Tokyo) Town in the Edo Period
(1603-1867). The people living in Edo used to visit these locations
for viewing the flowers in spring. Its cultivation methods were
introduced in the first gardening book (published in Japan)
KADAN KOOMOKU in 1681. At the beginning of the Edo Period,
wealthy merchants and SAMURAI (warrior class) people came to
grow them as pot plants. Later, even common people started to
appreciate them at the end of Edo Period. Eighty-eight cultivars
were introduced in the illustrated book SAKURASOU KAHINZEN
(= all the cultivars of Primula sieboldii, published in 1812).
Cultivars of those days have been preserved by enthusiasts up
until now. The famous botanist Dr. Phillip Franz von Siebold
introduced this species to western countries in the 19th century
and thus it is called Siebold's primrose. In recent years, Primula
sieboldii cultivars have became popular again. There are several
enthusiast groups of this species in Japan, and they are trying to
increase the population of Japanese primrose lovers.

Growing Tips: prefer drained soil like a mixture of leaf mold and
small-sized pumice but you can grow it in any soil; its soil should
always be moist since it grows in damp areas; loves sunny place
in spring; half-hardy.
After its blooming period, it is important to add soil onto its leaf
axis because it makes leaf buds for the next year above its leaf
axis. This behavior is caused by the circumstance of its habitat.
Its habitat is damp areas by a river. New soil covers its leaf axis
every year.
It is also important to give it fertilizer for a few months (May-
June in Japan) after its blooming period so that it will form new
flower buds. Place it in a sunny place late spring (April-June in
Japan), then move it to a half-shade place at the beginning of
summer (July in Japan). In late summer (August in Japan), its
leaves die and only its leaf buds and roots remain alive in the soil
until the following spring.
It is important that the soil be kept moist throughout the year. In
Japan, generally people grow it in a pot and keep water in its
saucer so that the soil in the pot will always be moist. In autumn,
you have to replant its dormant roots in new soil.

Primula sieboldii Websites
The Naniwa
Sieboldfs primrose
As a supporter group of Siebold's primrose, The Naniwa Siebold's primrose Association was started by over ten people sharing the same interest in 1936. This association does various studies on Siebold's primrose, preservation of species, exhibitions and announcements, distribution of seedlings, member's gatherings and publication of journals.
Wow! I am so surprised to know that there is an association of Primula sieboldii in the U.S.! You can get further information on this species by visiting the website. They have bred so many new cultivars and you can check the photos of their beautiful flowers.

KADAN, the Traditional Display Style of
SAKURASOO (Primula sieboldii) cultivars

Primula sieboldii cultivars are planted in pots and displayed on a
showing place under the roof. This traditional display style is
called KADAN (= flower platform) in Japanese. Primula sieboldii
exhibitions in KADAN style are held in spring in several places in
Japan. You can check the photos of the exhibition held in UKIMA
Park in Flower Events page, Click Here!

SAKURASOO (Primula sieboldii) cultivars






the oldest cultivar
since the early 18th century