Root.
Iris pallida root has numerous uses and supplies Orris powder, which has a high demand in perfumery industry. The dried up roots of the plant are pulverized to obtain Orris, whose aroma is akin to that of violets. In addition to being used in the form of a fixative in perfumes as well as potpourri, Orris root is also used in the manufacture of breath fresheners, toothpastes and similar products. It is also widely used in the form of a food essence. It may take several years for Iris pallida roots to dry properly so as to develop the right fragrance. The flavour of the fresh root of this plant is acrid and it is almost fragrance-free. The fresh roots yield an essential oil and it can be used for the same purposes for which the dried roots are used. The root also yields a black dye, while the flowers yield a blue dye. Besides growing the plants for its attractive, aromatic flowers and its roots, you may also cultivate Iris pallida for ground cover. The roots of this plant are so densely matted that they do not allow any weed to grow. Occasionally, the juice extracted from Iris pallid roots is employed in the form of a cosmetic and it also helps to get rid of freckles on the skin. The juice obtained from the fresh roots is a potent cleanser and can be used effectively for treating dropsy (a condition that was earlier known as edema). The dried roots can be pounded into a powder and used to flavour foods. In fact, the fresh root is almost neutral and does not have any fragrance. It generally takes many years for the dried roots to develop their characteristic fragrance. The dried roots of Iris pallida yield an essential oil called the "Orris oil", which is used to add essence to sweets, soft drinks, chewing gums and other food products.
Iris pallida needs a well-drained limey soil and sunlit position to achieve optimum growth. When grown in sunlit position, it is very easy to cultivate this plant in any common garden soil. Its preferred pH level ranges between 6.0 and 7.5. However, it can grow well in soils having a higher pH. Plants that have established themselves well possess the aptitude to tolerate drought conditions. Iris pallida is mainly cultivated for the essential oil contained in its roots, particularly in Italy. The flowers of this plant have a sweet aroma that will possibly remind you of orange blossoms. Some people also compare the aroma of Iris pallida flowers to that of vanilla, grape or civet. This is a very vigorously growing species. The rhizome of this plant should be placed slightly above the level of the soil. Plants belonging to this genus are seldom, if ever, disturbed by rabbits or browsing deer. Propagation: Iris pallida is mainly propagated by its seeds, which should be ideally sown in a cold frame immediately after they ripen. When the seedlings have grown large enough to be handled, you should prick them out individually and plant them in separate containers or pots and continue growing them in a cold frame or a greenhouse at least for the first year of their existence. The grown up young plants can be planted outdoors into their permanent positions either during the end of spring or the early part of summer. It is also possible to cultivate Iris pallida by means of root division. Although it is best to undertake root division of this plant soon after its flowering season, you can also do it throughout the year. Growing this plant from its root divisions is very easy and you can directly plant the larger root clumps outdoors in their permanent position. However, if the clumps are small you should plant them in pots and continue growing them in a cold frame till they root properly. Ideally, you should plant them outdoors during the spring. The soft young shoots may be victims of snail and slug invasions. In addition, bacterial infections may result in extensive discoloration (blighting) of the leaves. Other problems may include crown disintegration or decay.
Chemical analysis of orris root has revealed that it primarily contains the oil of orris in measures of anything between 0.1 percent and 0.2 percent. Oil of orris is a pale yellowish to yellow mass that encloses approximately 85 percent of neutral or fragrance-free myristic acid, which is apparently released from a type of fat found in the plant's rhizome when it is processed or steam distilled. Commercially, the oil of orris is known as Orris butter. In addition to the oil of orris, the plant also contains resin, fat, large amounts of starch, a bitter-tasting extract, mucilage and a glucoside called iridin. It is important that you don't mistake iridin for the powdered extract called irisin or iridin. In fact, the extract iridin or irisin is made from the rhizome of another Iris species known as the Iris versicolor, which is basically an American plant.
As several plants belonging to this genus are believed to be poisonous when taken orally, it is advised that you exercise caution while using these plants. In fact, the roots of these plants are more likely to be noxious. In some people, these plants may cause allergies and skin irritations.