Rosa obtusifolia
Family: Rosaceae
What it is like
Rosa obtusifolia is a deciduous Shrub. See above for USDA hardiness. It is hardy to UK zone 5. It is in flower from June to July. The species is hermaphrodite (has both male and female organs) and is pollinated by Bees. 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): 0
Where it is found
Hedges, scrub etc in England and Wales.
Europe, including Britain, from Scandanavia south and east to France, Italy, Roumania and Greece.
Conservation Status:
Countries/locations it is found in
How it is used
Food
Rating: 2
Fruit - raw or cooked. Rich in vitamin C. 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.
Seed: includes nuts, cereals, peas and beans.
Medicine
Rating: 1
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.
Cancer: Used in the treatment of cancer.
Vitamin C: Plants good for their vitamin C content
Other
Rating:
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. 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. Closely related to R. canina. 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 shorten 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 should 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. tomentella.