2006 Herb of the Year
Scented Geraniums
  Pelargoniums
In 2006, the following information was included in The New England Unit's Guide to the Teaching Herb Garden. The same year, several varieties of these fragrant plants were featured in our display garden at Elm Bank. You can still find scented geraniums in our  "Fragrance" garden. Pelargoniums are grown as tender perennials in New England, and need to be wintered indoors. Grown more for their interesting foliage and scented leaves, these plants never fail to delight.
Scented Geraniums are the 2006 Herb of the Year. They are not true geraniums, but Pelargoniums, a separate genus in the  geranium family. They are native to South Africa, discovered there in the 17th century. Growing them became popular in the  mid-18th century. The French soon began extracting the essential oil as a cheaper alternative to Attar of Rose oil for perfumery.

Scented geraniums need full sun and well-drained, loamy soil that is slightly acidic. Magnesium promotes good growth but  excess nitrogen will diminish their scent. They prefer to dry somewhat between waterings. Watch for fungal problems. The plants are tender perennials in our zone, and so must be wintered indoors. Indoors, they can be vulnerable to various pests which can be treated with insecticidal soap.

Plants range in size from 12 inches to three feet. The flowers are rather insignificant since the leaves produced the scent. Leaves range from ½  inch to 3 inches, are green or gray, and have textures that are shiny, fuzzy, sticky or velvety. There are many scents [including] rose, mint, lemon, chocolate, pine, apricot and more. Pelargoniums have many uses including perfumery, aromatherapy, cooking,  potpourri. An  excellent book is Scented Geraniums, by Jim Becker and Faye Brawner, Interweave Press, 1996.
Also visit the HSA Library to view Pelargoniums: An Herb Society of America Guide. This comprehensive guide is one in a series featuring the current "Herb of the Year."
Link opens in new  brower window.
Pelargoniums: An Herb Society of America Fact Sheet
http://www.herbsociety.org/herbs/profiles-and-guides.html
Edited to add another good book on scented geraniums
Scented Geranium – Pelargonium: 2006 Herb of the Year, by Pat Crocker, Caroline Amidon and Joyce Brobst. Neustadt, Ontario: Riversong Studios Ltd., 2006.
To order, contact Pat Crocker
HSA members Pat Crocker, Caroline Amidon and Joyce Brobst provide information on Pelargonium history, folklore, nomenclature/classification, botany, varieties, cultivation, propagation, pests/diseases, and landscape and culinary uses. The nomenclature section includes a description of five Pelargonium sections. The varieties section includes descriptions of 20 species and 41 cultivars, organized by fragrance and illustrated with black and white and color photographs. The book also includes a resource list, bibliography and index, and a variety of recipes for scented infusions, grains, chicken, fish, pork and beef, desserts, and beverages.