The fruit attracts many species of birds, several gall wasps and other insects use the plant as a host.

The leaves, when bruised, have a delicious fragrance. The flowers are also fragrant. 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.

Succeeds in most soils. Grows well in heavy clay soils. Prefers a circumneutral soil and a sunny position with its roots in the shade. When grown in deep shade it usually fails to flower and fruit. Succeeds in wet soils but dislikes water-logged soils or very dry sites. Tolerates maritime exposure.

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.

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.

Edible uses:

Fruit - raw or cooked. It can be used in making delicious jams, syrups etc. The syrup is used as a nutritional supplement, especially for babies. The fruit can also be dried and used as a tea. Frost softens and sweetens the flesh. 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 dried leaves are used as a tea substitute. 

Petals - raw or cooked. The base of the petal may be bitter so is best removed. Eaten as a vegetable in China. The petals are also used to make an unusual scented jam.

http://practicalplants.org/wiki/Rosa_canina