Cycas Revoluta or Japanese Sago Palm is neither a palm nor a tree fern but part of the genus Cycas that is rather related to the conifers.
It is a living fossil from the Carboniferous era, from Japan and the Chinese coast.
It can be quite old, 50 to 100 years, and older specimen can be 6 to 7 m high. In the United Kingdom is a specimen that is said to be 220 years old.
Cycas Revoluta is a tree with a pseudo-stem of 1-3 m high and 20-45 cm in diameter.
At the top of the stem is a crown with 40 to 100 leaves. The leaves are green, tough and pinnate, 70-150 cm long and 20 to 25 cm wide when the plant is sexually mature. On both sides of the central vein is a row of small folioles of 10 to 20 cm long and 4 to 7 mm wide, ending in a sharp point. The leaf stalk is 6 to 20 cm long and both sides are covered with thorns.
The plant is dioecious and the flowers grow in the center of the leaf crown. The male inflorescence is a cone of 30 to 60 cm high and 8 to 15 cm in diameter. It is formed by elongated scales that bear sporangia at the bottom, where the pollen is located. The female inflorescence is composed of fluffy, beige-coloured small leaves with a few ova. Fertilization takes place 6 months after pollination.
The seeds are quite large, 3 to 4 cm, and reddish brown in color. Growth is very slow: 1 m in 20 to 30 years.
Beware: the plant is toxic in all parts!
Japanese Sago Palm, King Sago, King Sago Palm, Sago Cycas, Sago Palm, Sotesu-Nut
Cycas miquelii, Cycas revoluta var. brevifrons, Cycas revoluta var. planifolia, Cycas revoluta var. prolifera, Cycas revoluta var. robusta, Epicycas miquelii
Cycas: from the Greek cyca (palm tree)
Revoluta: from the Latin revolutus (curled back)
Japan and south-east coast of China.
On the islands it grows in thickets on slopes, on the mainland in light woods, between 0 and 1,000 m altitude.
USDA zone 8-11, -8 °C
Sandy added with humus, well-draining
Sun, light, partial shade, shadeGrown in shade, it will form bigger leaves.
Water abundantly the first season so the root system is well established. Later waterings can be reduced. Adult plants are drought resistant.
Prefers a solid fertilizer which releases nutrients slowly or a very diluted liquid fertilizer. Avoid strong fertilizer or fresh manure because they might damage the roots. Fertilize regularly during growing season the promote the growth, about every 2 weeks.
Often grown as indoor plant but prefers to spend the summer outdoors. In USDA zone 8 it is best to bring the plant inside to protect from severe frost or to provide winter protection. Young plants are not as frost resistant: -5 °C for young plants, between -8 °C and -10 °C for mature plants.
- fresh seed is best left to mature in a cool place for 2-3 months
- soak de seeds 1-2 days in lukewarm water
- plant the seeds in moist sand
- 25-30 °C
- germination time: 2-3 months
- it is best to take suckers off in the winter: the plant itself doesn’t grow but root growth is ongoing during winter
- remove all the leaves
- plant in a moist, well drained and sandy substrate
- Cycas revoluta: Own work
- Cycas revoluta female cone: Own work
- Cycas revoluta male cone: Own work