The Rue plant, Ruta graveolens, is an aromatic perennial subshrub native to the Mediterranean region. Often called Common Rue or Herb-of-Grace, this plant has been cultivated for centuries. It is a distinctive garden specimen, recognizable by its unique, finely divided, blue-green foliage. Rue is valued for its appearance and traditional uses, but requires careful handling due to its natural chemical compounds.
Identifying Rue (Ruta graveolens)
Rue belongs to the Rutaceae family (the citrus family). It typically grows as a woody, clump-forming perennial or subshrub, reaching a height and width of about two to three feet. Its most notable feature is the glaucous, blue-green foliage, which is bipinnately divided, giving it a soft, feathery texture. The leaves are covered in oil glands, and when bruised, they release a strong, pungent aroma.
In the summer months, small, four- or five-petaled, dull greenish-yellow flowers appear in clusters above the foliage. The plant will eventually produce small, lobed seed capsules. Due to its shrubby habit and color, it is easy to identify in a garden setting, particularly where it is used as a low, ornamental edging plant. The entire plant, especially the foliage, contains the compounds responsible for its strong scent and its phototoxic properties.
Essential Safety Precautions and Handling
The most serious consideration when handling Ruta graveolens is its potent phototoxicity, which can cause phytophotodermatitis. This reaction is triggered when the furanocoumarin compounds in the plant’s sap contact human skin and are subsequently exposed to ultraviolet light from the sun. The result is a severe, burn-like reaction that includes intense redness, blistering, and hyperpigmentation lasting for months.
Handling the plant requires mandatory safety measures, including wearing long sleeves and waterproof gloves to prevent direct skin contact with the leaves or stems. It is advisable to prune or work with Rue during overcast days or in the evening, avoiding exposure to direct sunlight after contact has occurred. The chemical reaction is a photo-irritant, meaning it affects nearly everyone exposed.
Beyond external contact, the plant is toxic if ingested, containing compounds like alkaloids and volatile oils that cause significant internal damage. Consuming large amounts can lead to severe gastrointestinal distress, vomiting, and potentially acute liver and kidney failure. Historically, Rue was used to induce menstruation and as an abortifacient, leading to documented cases of severe toxicity and death. This strongly underscores that the plant is not safe for internal use.
Common Applications and Historical Uses
Despite its toxicity, Ruta graveolens is sought after for its ornamental value, particularly its distinctive, year-round blue-green color. It is a resilient plant, prized by gardeners for its ability to tolerate drought and poor, dry soils once established. Its strong aroma also makes it naturally resistant to deer.
The Rue plant serves as a host for the caterpillars of certain Swallowtail butterflies, making it a desirable addition to pollinator-focused gardens. Historically, the plant was woven into folklore and traditional practices, associated with warding off evil, contagion, and insects. In some Mediterranean and Ethiopian traditions, dried leaves or seeds are still used sparingly as a bitter seasoning or in alcoholic beverages like Grappa.
Sourcing the Rue Plant
When looking to acquire Ruta graveolens, you have a few practical options, depending on your desired planting timeline and experience level. For immediate planting, local garden centers and specialty nurseries are the most common sources for established starter plants. These are typically available in the spring and early summer. Purchasing a live plant ensures you get a mature specimen with the characteristic blue-green foliage already developed.
For a more cost-effective option, or if you prefer to start from scratch, seeds are widely available through online specialty retailers. Rue seeds are best started indoors four to six weeks before the last expected frost, requiring light and consistent moisture for germination. Established perennial plants offer quicker garden impact, while seeds provide a greater quantity for mass planting or hedging.
If your interest lies in traditional or culinary uses, dried Rue leaves or seeds can be sourced from reputable herbal suppliers or spice merchants. When buying dried forms, it is important to verify the plant’s identification, ensuring you are purchasing Ruta graveolens and not an unrelated plant like meadow rue (Thalictrum species). Regardless of the source, always prepare to handle the live plant with the recommended safety precautions.