California Wild Rose
Rosa californica
Family: Rosaceae
What it is like
Rosa californica is a deciduous Shrub growing to 2.5 m (8ft) by 2 m (6ft). See above for USDA hardiness. It is hardy to UK zone 5. It is in flower from June to July, and the seeds ripen from August to October. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. The plant is self-fertile. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in heavy clay soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.
Height (m): 2.5
Where it is found
By rivers and in moist canyons.
South-western N. America - California.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 2
Fruit - raw or cooked. Eaten raw when it becomes soft after a frost, it is much esteemed. Rich in vitamins A and C. The fruit is about 15mm in diameter, but there is only a thin layer of flesh surrounding the many seeds. Some care has to be taken when eating this fruit, see the notes above on known hazards. The seed is a good source of vitamin E, it can be ground and mixed with flour or added to other foods as a supplement. Be sure to remove the seed hairs. The blossoms have been soaked in water to make a beverage.
Seed: includes nuts, cereals, peas and beans.
Drink: not including plant saps, tea or coffee substitutes.
Medicine
Rating: 2
An infusion of the blossoms has been used as an analgesic and febrifuge in treating pain and fevers in infants. A decoction of the hips has been drunk in the treatment of kidney complaints, indigestion, rheumatism, sore throats, fevers and colds. A decoction of the hips has been used as a wash on scabs and sores. An infusion of the seeds has been used in the treatment of stomach fevers and painful congestion. The fruit of many members of this genus is a very rich source of vitamins and minerals, especially in vitamins A, C and E, flavanoids and other bio-active compounds. It is also a fairly good source of essential fatty acids, which is fairly unusual for a fruit. It is being investigated as a food that is capable of reducing the incidence of cancer and also as a means of halting or reversing the growth of cancers.
Analgesic: Relieves pain.
Antirheumatic: Treats rheumatism.
Cancer: Used in the treatment of cancer.
Febrifuge: Reduces fevers.
Kidney: Used in the treatment of kidney diseases
Salve: Soothes and heals damaged skin.
Stomachic: Aids and improves the action of the stomach.
Other
Rating: 2
An essential oil is obtained from the flowers and leaves, it is used in perfumery. The unsplit stems have been used as rims in twined basketry.
Basketry: Plant used in making baskets and other items such as chairs. Includes plants that are only used as an ornamental addition.
Essential: Essential oils that are used in perfumery, medicines, paint solvents, insect repellents etc.
Scented Plants: Plants noted for their scent
How it is grown
Succeeds in most soils, preferring a circumneutral soil and a sunny position. Grows well in heavy clay soils. Dislikes water-logged soils. The flowers have a rich perfume. Grows well with alliums, parsley, mignonette and lupins. Garlic planted nearby can help protect the plant from disease and insect predation. Grows badly with boxwood. The plant that is most commonly grown under this name is in fact R. nutcana. Hybridizes freely with other members of this genus. Plants in this genus are notably susceptible to honey fungus.
Propagating it: Seed. Rose seed often takes two years to germinate. This is because it may need a warm spell of weather after a cold spell in order to mature the embryo and reduce the seedcoat. One possible way to reduce this time is to scarify the seed and then place it for 2 - 3 weeks in damp peat at a temperature of 27 - 32°c (by which time the seed should have imbibed). It is then kept at 3°c for the next 4 months by which time it should be starting to germinate. Alternatively, it is possible that seed harvested 'green' (when it is fully developed but before it has dried on the plant) and sown immediately will germinate in the late winter. This method has not as yet(1988) been fully tested. Seed sown as soon as it is ripe in a cold frame sometimes germinates in spring though it may take 18 months. Stored seed can be sown as early in the year as possible and stratified for 6 weeks at 5°c. It may take 2 years to germinate. Prick out the seedlings into individual pots when they are large enough to handle. Plant out in the summer if the plants are more than 25cm tall, otherwise grow on in a cold frame for the winter and plant out in late spring. Cuttings of half-ripe wood with a heel, July in a shaded frame. Overwinter the plants in the frame and plant out in late spring. High percentage. Cuttings of mature wood of the current seasons growth. Select pencil thick shoots in early autumn that are about 20 - 25cm long and plant them in a sheltered position outdoors or in a cold frame. The cuttings can take 12 months to establish but a high percentage of them normally succeed. Division of suckers in the dormant season. Plant them out direct into their permanent positions. Layering. Takes 12 months.
Best place to grow: Woodland Garden Sunny Edge; Dappled Shade;
Habit: Shrub
Hardiness: 4-8
Growth:
Soil: Light (sandy), medium, heavy (clay)
Shade: Semi-shade, no shade
Moisture: Moist
Things to keep in mind
There is a layer of hairs around the seeds just beneath the flesh of the fruit. These hairs can cause irritation to the mouth and digestive tract if ingested.
Its other names
Local names
Synonyms
R. aldersonii. R. breweri. R. myriantha.