Cryptomeria japonica 'Spiralis'

Michael's Opinion

Cryptomeria japonica ‘Spiralis’ is a very eye-catching evergreen with bright green foliage. It is a tree from the Cupressaceae family. Another common name it has, ‘Granny Ringlets’, describes the habits of the foliage on this unique cultivar. The needles twist spirally around the branches, giving the plant its distinctive look. As Cryptomeria japonica ‘Spiralis’ matures it starts mounding, later developing an upright leader. However, it can be pruned to keep rounded form. It’s pretty hardy and prefers colder temperatures around -6°C - 0°, and looks the most attractive in the winter time. ‘Spiralis’ doesn’t produce flowers or fruit, so it is propagated by cuttings and is not used in the landscape as much as I thought for being such a unique cultivar.

Botanical Information

FamilyCupressaceae
GenusCryptomeria
Speciesjaponica
Cultivar'Spiralis'
CategoryWoody
TypeTree (evergreen)
OriginOriginated in Japan in the mid 1800s, the cultivar name was published in 1844 by Siebold and Zuccarini.
Ethnobotanical Uses
Disclaimer		Cryptomeria japonica was extremely important in early Japanese society, both for a source of building materials and for its spiritual aspects. Traditional Japanese culture places high value on natural items, and this attitude persists to the modern day. The ancient Japanese religion of Shinto represented a connection between man and nature and tall trees had special significance. Cryptomeria japonica are found at the centre of many Shinto shrines.

Details

USDA Hardiness Zone5 - 7
USDA Hardiness Ref.
Canadian Hardiness Zone5b - 9a
Canada Hardiness Ref.
RHS Hardiness ZoneH4
RHS Hardiness Ref.
Temperature (°C)(-6)
Temperature (°F)20
Height6 - 10
Spread7 - 8
GrowthMedium

Description and Growing Information

General DescriptionA medium to large evergreen and moderately slow growing Japanese Cedar cultivar. The light green foliage of ‘Spiralis’ twists around the branches throughout the entire plant, hence the name spiral.
ID CharacteristicHas light green, awl type foliage that spirals around the branches. When young the plant is more rounded, but as it matures it becomes more pyramidal. This cultivar is also non-flowering.
ShapeRounded and dense for the first 10-15 years of its life. When matured it will develop an upright leader making the plant more pyramidal.
LandscapeCryptomeria japonica ‘Spiralis’ only has a couple uses in the landscape. It’s a vigorous, globe shaped plant when young. ‘Spiralis’ will develop a leader and a broad, upright habit that makes a dramatic impression in the landscape as an accent or specimen plant. It can also be used as a screen when mature because of its density.
PropagationPropagation of Cryptomeria japonica ‘Spiralis’ is best done from semi-hardwood cuttings. Semi-hardwood cuttings generally root easily and don’t require a lot of extra knowledge. You take cuttings from the growing tips of the plant, ideal lengths are 4-6 inches using your pruners. The cutting should be healthy and have no signs of pests or disease. Plant the semi-hardwood cutting in a container filled with unfertilized potting mix and coarse sand. Water the cutting well and cover it with doms for moisture. Place in indirect sunlight because direct sunlight may be too harsh and scorch the cutting.
CultivationPrefers to be grown in full sun in a sheltered location. Tolerates most soils, but thrives in sandy, well-drained soils. Proper pH should be acidic to neutral soils with an ideal 5.0-7.0 pH. It’s slightly salt tolerant and completely tolerant to deer.
PestsHas no serious insect or disease problems. Leaf blight and leaf spot are the only two diseases that can affect this cultivar.
Notable SpecimensThere is a notable specimen in the Akatsuka BotanicalGarden in Itabashi, Tokyo, Japan.
HabitatHorticultural Origin.
Bark/Stem DescriptionSlightly pendulous branches, with exfoliating reddish bark.
Flower/Leaf Bud DescriptionHas bare, light brown coloured buds about 1-2 cm long.
Leaf DescriptionHas short, light green awl-like foliage that covers the entire branch top to bottom by spirally wrapping around it. Also mildly variegated on the tips of branches.
Flower DescriptionCryptomeria japonica ‘Spiralis’ is a sterile cultivar and does not produce flowers.
Fruit DescriptionCryptomeria japonica ‘Spiralis’ is a sterile cultivar and does not produce fruit.
Colour DescriptionLeaves stay the same light green colour all year long, until it matures and is at full height where the foliage turns a darker shade. The bark is mostly brown with a reddish tint.
Texture DescriptionMedium.

Photographs