The fragrances of plants probably evolved as essential to their survival. Many flowers produce odors that attract pollinators while other plant parts may produce essential oils. Essential oils are volatile substances (evaporating at room temperature) which impart the characteristic aroma or flavor to the plant. The function of these oils is not fully understood, but it is speculated that they may deter leaf-eating predators, act as defense mechanisms against pathogens, play a role in metabolism, or enhance the attractiveness of typically inconspicuous flowers.

Herb fragrances have long been valued to mask unpleasant odors, lift the spirits, evoke memories, freshen the air, and scent cosmetics, perfumes, and household products. In fact, the use of perfume dates back to ancient Egypt where it enhanced royal and religious ceremonies.

Refinement of extraction techniques enabled more people to enjoy herb fragrances in myriad scented products. Three basic techniques exist for the extraction of essential oils: steam distillation, which evaporates the oils from the plant material via steam; expression, which forces oils out of the plant by pressure; or extraction, which employs solvents to draw oils from the plant.

The rising cost of perfume production coupled with a growing demand for fragrance compounds necessitated the substitution of naturally-obtained fragrances with synthetic aroma chemicals. These synthetics are added to stretch the limited supply of essential oils; however, in most cases some degree of natural material must be included to convincingly mimic the desired aroma.

Artemisia absinthium-- Wormwood (perennial)

Special Considerations: Wormwood contains large amounts of absinthin, a water-soluble substance toxic to other plants. Rain water washes absinthin off the leaves into the soil, where it inhibits the growth of surrounding plants.

Historical Use: An Egyptian papyrus dating from 1600 BC described wormwood as a medicine to rid the body of worms. The leaves and flowering tops were used to make an addicting liqueur called absinthe. Vincent Van Gogh was allegedly under its influence when he cut off his own ear.

Aromatic Use: Wornwood leaves are added to sachets to repel moths.

Other Uses: Medicinal; Household-- companion planting, insect repellent.

Lavandula angustifolia cv. Munstead-- Dwarf Lavender (perennial)

Special Considerations: Lavender requires winter protection.

Historical Use: See "Household Uses of Herbs".

Aromatic Use: Dwarf lavender possesses the same pleasant fragrance as Lavandula officinalis, and is used to scent sachets, potpourris, perfumes, toilet water, and hygiene products. Well-dried flowers retain their scent for a long time.

Other Uses: See "Household Uses of Herbs".

Mentha piperita-- Peppermint (perennial)

Historical Use: Fresh or dried bunches of peppermint were hung about the house to freshen the air.

Aromatic Use: Peppermint makes a nice addition to potpourris.

Other Uses: Peppermint is known for flavoring candy. It is also used in teas.

Mentha pulegium-- Pennyroyal (perennial)

Historical Use: Pennyroyal was rubbed on the skin to repel insects. Medicinally, it served as an abortive, laxative, expectorant, and emetic.

Aromatic Use: The peppermint-scented leaves are added to potpourris and sachets.

Other Uses: Medicinal; Household-- insect repellent.

Rosa sp.-- Rose (perennial shrub)

Special Considerations: Roses require 6-8 hours of full sun per day and do not tolerate crowding.

Historical Use: Romans crowned bridal couples with roses and placed them as banquet centerpieces. People often were sworn to silence with a bribe of roses, thus the rose became a symbol of confidences. The expression "sub rosa" (literally "under the rose") means "in greatest confidence". The American Indians used roses medicinally to treat sores, blisters, and as an eye wash.

Aromatic Use: Rose flowers scent perfumes, sachets, potpourris, bath oils, and hygiene products.

Other Uses: Medicinal; Culinary; Household--cleansing, decorative.

Rosmarinus officinalis-- Rosemary (tender perennial evergreen shrub)

Special Considerations: Rosemary must be brought inside to overwinter.

Historical Use: Students wore rosemary garlands while studying for exams to help their memory. It was useful medicinally and as a room deodorizer. During World War II, rosemary branches were burned to disinfect the air in sickrooms (this has an antibacterial effect). Rosemary traditionally is the symbol of remembrance, friendship, and love.

Aromatic Use: Rosemary oil adds a piney scent to hygiene products, lotions, perfumes, and toilet water. The leaves are added to sachets and potpourris.

Other Uses: Medicinal; Culinary; Household-- cosmetic, disinfectant; Dye.

Thymus X citriodorus-- Lemon Thyme (perennial)

Special Considerations: Lemon thyme is more tender than common thyme and needs protection from winter winds.

Historical Use: See "Culinary Uses of Herbs".

Aromatic Use: The dried flowers and leaves of lemon thyme are used to scent sachets, colognes, hygiene products, and detergents.

Other Uses: See "Culinary Uses of Herbs".

Ruta graveolens v. blue mound-- Rue

Special Considerations: See "Medicinal Uses of Herbs".

Historical Use: See "Medicinal Uses of Herbs".

Aromatic Use: Glands distributed over the entire plant contain a volatile oil that is responsible for the characteristic odor of rue. Bruising the foliage will release the smell. Rue oil is obtained by distilling the leafy portions of the plant and is used in perfumes and in the manufacture of aromatic, toilet, hygienic, and cosmetic vinegars.

Other Uses: See "Medicinal Uses of Herbs".

Viola sp.-- Violet (perennial)

Special Considerations: Violets self sow readily.

Historical Use: Records of the violet date back to the ancient Greeks; the scribes Herodotus and Pliny wrote about its medicinal virtues. The theory that unpleasant odors are less potent after smelling a violet led to the violet's use as a stewing herb in the Middle Ages.

Aromatic Use: The violet once played a prominent role in the perfume industry, but was superceded by synthetic aroma chemicals. It still is added to potpourris although the fragrance is not lasting.

Other Uses: Medicinal; Dye; Culinary.

Pelargonium spp.-- Scented Geranium (annual)

Special Considerations: Scented geraniums may act as a trap crop for Japanese beetles.

Historical Use: Scented geraniums were introduced to Europe in 1690 from South Africa by sailors. In the mid-1800's, rose-scented geraniums began to be substituted for attar of roses in French perfume making, thus increasing their popularity. In the Victorian era, scented geraniums had culinary, medicinal, and decorative applications.

Aromatic Use: Scented geraniums are grown commercially for their fragrant leaf oils which perfume tooth powders, soaps, sachets and potpourris, and ointments. Commercially produced geranium oils vary in fragrance depending on their country of origin.

Other Uses: Culinary; Household-- decorative, cosmetic, companion planting.

Santolina chamaecyparissus-- Lavender Cotton (perennial)

Historical Use: Lavender cotton originally was valued for its medicinal astringent properties. As it spread to England in the Elizabethan era, it was planted ornamentally as a compact hedge plant.

Aromatic Use: Lavender cotton has a musky fragrance which makes an interesting addition to potpourris and sachets.

Other Uses: Household-- insect repellent, decorative; Dye.

Iris X germanica v. florentina-- Orris (perennial)

Special Considerations: The rhizomes should be divided every 3-4 years in the summer after flowering, leaving half of the divided bulb above the soil surface.

Historical Use: Ancient Egyptians and Greeks discovered the potent violet fragrance of the orris root which must be dried for two years to develop. The root possess medicinal and breath freshening attributes. The name "florentina" originates from its history in Florence, Italy where commercial cultivation of orris for perfume making began in the Middle Ages.

Fragrance Use: Orris acts as a fixative, a substance that slows the evaporation of essential oils, prolonging the life of herbal potpourris. The violet fragrance of the roots is exploited in the perfume industry. The powdered rhizome or its essential oil flavors liqueurs, soft drinks, candy and gum; it is valued today as a base for dry shampoos and tooth powders.