Japanese Sago Palm, Sago palm, King Sago Palm
Cycas revoluta
Family: Cycadaceae
What it is like
Form: Palm.
Cycas revoluta is an evergreen Tree growing to 3.5 m (11ft) by 3.5 m (11ft) at a slow rate. See above for USDA hardiness. It is hardy to UK zone 9 and is frost tender. It is in leaf all year, in flower from May to July, and the seeds ripen from October to November. The species is dioecious (individual flowers are either male or female, but only one sex is to be found on any one plant so both male and female plants must be grown if seed is required). and is pollinated by Insects, wind. The plant is not self-fertile. It can fix Nitrogen. Suitable for: light (sandy) and medium (loamy) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers dry or moist soil.
Height (m): 3.5
Where it is found
Found mainly on the sea shore in S. Japan. Thickets on hillsides on islands, sparse forests on mainland at elevations of 100 - 500 metres in Fujian, China.
E. Asia - China, Japan.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 2
Seed - raw or cooked. They can be dried and ground into a powder then mixed with brown rice and fermented into 'date miso' or 'sotetsu miso'. Caution is advised, see the notes above on toxicity. The heart or pith of the trunk is sliced and eaten baked or powdered. A toxic principal must first be removed. A starch can be extracted from this pith and is used for making dumplings. It is very sustaining.
Seed: includes nuts, cereals, peas and beans.
Stem: this often intergrades into leaves.
Medicine
Rating: 2
The leaves are used in the treatment of cancer and hepatoma. The terminal shoot is astringent and diuretic. The seed is emmenagogue, expectorant and tonic. It is used in the treatment of rheumatism. Substances extracted from the seeds are used to inhibit the growth of malignant tumours.
Astringent: Produces contraction in living tissue, reducing the flow of secretions and discharges of blood, mucus, diarrhoea etc.
Cancer: Used in the treatment of cancer.
Diuretic: Acts on the kidneys, promoting the flow of urine.
Emmenagogue: Promotes or increases the menstrual flow. In early stages of pregnancy it can induce an abortion.
Expectorant: Clears phlegm from the chest by inducing coughing.
Tonic: Improves general health. Slower acting than a stimulant, it brings steady improvement.
Other
Rating:
Nitrogen Fixer: Plants that fix nitrogen in the soil
How it is grown
Landscape Uses:Border, Container, Massing, Seashore, Specimen. Requires a strong loam with sharp sand and good drainage. Succeeds in dry soils. Requires a sunny position. Although it is the hardiest cycad, this species is not fully hardy in Britain but can tolerate occasional lows to about -5°c so long as the crown is protected and so is worthwhile trying outdoors in a sheltered position in the mildest areas of the country. Alternatively, it can be given greenhouse or conservatory protection over the winter and be placed outdoors in the summer. Plants are very slow growing. This plant is often used as a food source in its native range but recent research has shown that it can cause chronic nervous disorders if it is not treated properly. Overall its use is not to be recommended, especially since it is becoming rare in the wild. The plants produce special upward growing roots where nitrogen is produced in symbiosis with algae. Dioecious, male and female plants must be grown if seed is required. Special Features:Attractive foliage, Not North American native, All or parts of this plant are poisonous, There are no flowers or blooms.
Propagating it: Seed - best sown in a greenhouse as soon as it is ripe, 2cm deep in individual pots which are then sealed in plastic bags to keep them moist until germination takes place. Germinates in 1 - 3 months at 25°c. Pre-soak stored seed for 24 hours in warm water then treat as above. Division of suckers in the spring.
Best place to grow: Woodland Garden Sunny Edge; Dappled Shade; South Wall. By. West Wall. By.
Habit: Tree
Hardiness: 8-11
Growth: Slow
Soil: Light (sandy), medium
Shade: Semi-shade, no shade
Moisture: Dry, moist
Things to keep in mind
The plants contain alkaloids of carcinogens and also an amino-acid that causes chronic nervous disorders. Regular consumption of the plant leads to severe health problems and death. This toxic principle can be removed if the food is properly prepared but consumption of the plant still cannot be recommended because its use often means the death of the plant and it is becoming rare in the wild.