What is Happening in the Herb Garden and Kitchens This Week?

By Barbara F. Smith

Two herbs found in the medicinal beds of the BBG Herb Display Garden are the focus of attention today – watch out for skin irritations!

Ruta Graveolens, commonly known as Rue, Common Rue, or Herb of Grace, is a plant of great historical importance, but is less well known today (see photo above). The genus name “Ruta” comes from a Greek word meaning “to set free,” which suggests the herb’s reputation in treating diseases. Mrs. Grieve declared it to be one of the “best known and widely grown simples for medicinal and homely uses.” A simple is a preparation from a single herb plant, usually made for medicinal purposes.

Made use of for centuries as an antidote to poisons, Rue was also used externally to treat insect bites, gout, rheumatism, and sciatica, and internally to treat heart problems, worms, colic, and to improve digestion. Another resource described its historical uses as effective against “poisons of mushrooms, serpents, bees and scorpions, mad dogs and salamanders.” During the Middle Ages, Rue was considered a reliable defense against witches and their spells. Dried Rue leaves were strewn to rid rooms of fleas and protect inhabitants from the plague. Rue has been shown to have antimicrobial, antispasmodic, and analgesic properties. 

In a somewhat surprising legend from the 17th century, when plague was rampant in France, Rue was one of the components of the so-called “Vinegar of the Four Thieves.” The thieves, who entered homes of the sick and dying to steal their goods, first rubbed themselves with a herbal vinegar (with Rue as one component among other herbs) as protection, and they managed to stay alive. Once caught, the story goes that they won their freedom by sharing the source of their “protection.”

This graceful plant has fern-like, silver-blue leaves and simple yellow-green flowers. Native to Europe and northern Africa, it is categorized as a perennial subshrub, growing to about three feet tall.  It is not often grown in ornamental gardens, but its foliage is a standout in a herb garden. The plant’s fragrance is alternately described as “heavy smelling” or “distinctive.”  If its leaves are crushed, it “exudes a powerful musk similar to that of a tomcat, and the odor remains on the skin.” If you have sensitive skin, it is recommended that you wear gloves to handle the plant, or risk blisters and potential scarring. 

Rue is not widely used in food preparation, although some recipes may call for small amounts to be added to soups or stews. However, it is the most important herbal ingredient of the Italian distilled spirit “Grappa” – described as a ‘home-brewed moonshine’ made from fermented grape skins with a stem of rue added to impart a slight earthy taste.

Rue is a magnet for black swallowtail butterflies that lay eggs on its leaves, and whose caterpillars may defoliate the plant. It is also used in integrated pest management programs as a breeding area for a parasitic wasp, which naturally controls whiteflies in greenhouses.

The second herb of interest blooming this week in the medicinal bed is Dictamus albus, commonly known as the Gas Plant or dittany (see the photo above, surrounded by Walker’s Low Catmint, Nepeta faassenii). The Gas Plant blooms in May and June, with very showy spires in shades of white, pink or red, sometimes with veins or red dots on the petals. New plants may be started from seeds sown outdoors in the fall; they must go through the winter for cold stratification before they root and grow. Although the plants are slow to establish and may take 3-4 years before flowering, they are long-lived and require only low maintenance. Gas Plant flowers give way to star-shaped seed heads, which provide ornamental interest. The leaves have a pleasant lemony fragrance when rubbed or crushed, and the oils may cause contact dermatitis — a skin rash in some individuals. In hot weather, old flowers or seed pods emit a flammable oil that can be ignited with a match, resulting in a brief vapor burn, which is harmless to the plant.

Gas Plants are often used in cottage gardens, rock gardens, woodland, or border gardens. They are deer and drought resistant, and they attract many butterflies and pollinators.

WHAT’S HAPPENING WITH THE HERB ASSOCIATES KITCHEN CREW?

With the blooming period for chive blossoms coming to a close, Herb Associates in the Production Garden filled three baskets full of chive blossoms and stems. Ideally, when harvesting the blossoms, you pull the entire stem out from the base of the plant. Otherwise, when you later want to harvest chives, you’ll be dealing with the woody stems where the flower blossoms had bloomed.

Mouth-watering aromas filled the kitchen areas, as members of the Kitchen Crew chopped or stripped chives and chive blossoms, lemon verbena and lemon balm, and lovage. With all this goodness, the Kitchen Crew (some pictured above) assembled Chive Blossom Vinegar, a Lemon Balm Infusion, Lemon Verbena and Lemon Balm Jelly, Rhubarb-Ginger Jam, and Strawberry-Rhubarb Jam. The Chive Blossom Finishing Salt, a new product, was labelled (see photos above). Last but not least, more ever-popular catnip mice were added to all the Herb Associates products to be found in the BBG’s Gift Shop at the Visitor’s Center.

Particular resources this week:  

• “Essential Herbal Wisdom: A Complete Exploration of 50 Remarkable Herbs” by Nancy Arrowsmith (Llewelyn Publications, 2009)
• “The New American Herbal” by Stephen Orr (Clarkson Potter Publishers, 2004)
• “A Modern Herbal” by Mrs. M. Grieve (Harcourt, Brace and Company, 1931). Mrs. Maud Grieve was a British herbalist (1858-1941); her most famous contribution to herbal knowledge was this two-volume compendium