Opening my spiral-bound sketchbook, I catch a hint of vanilla from between its decade-old pages. The scent comes from a group of whorled leaves that I picked while making a drawing and pressed between thick sheets of cartridge paper. Set against a background of loose pencil marks, these are the star-shaped verticils of sweet woodruff, Galium odoratum, a UK native plant.
One of the indicators of ancient woodland, this is a perennial plant that grows in my local woods along with sanicle, dog’s mercury and the delicately arching grass, wood melick. A member of the madder family, its spoke-like arrangement of leaves and its four-angled stems show that it’s related to goosegrass, bedstraw and crosswort.
Like bedstraw, woodruff was once used to stuff mattresses and as a strewing herb. It is only when dried that the plant releases the soothing scent of vanilla and new‑mown hay, long-lasting, as my sketchbook pages show. This is due to the presence of coumarin, an aromatic chemical compound, banned as a food additive in some countries after studies found it to be toxic to rats and mice.
When I made my garden, I accidentally brought along some woodruff. It hitched a ride on iris rhizomes and I kept forgetting to unravel its fine exploratory roots. In the newly worked soil, it quickly spread among the plants of the shady border. Luckily, the clumps of brunnera, perennial honesty and other shade lovers manage to rise up through it. Now, as I tidy in preparation for emerging winter bulbs, I can smell the crushed woodruff as it dies back and dries out.
To press some leaves, I detach them from the stem by cutting above and below a whorl. Their rose-window shape can be used as a “resist”, pressed into clay and painted with underglaze, or to create a silhouette in artwork or sun prints. In spring, the emerald greenery of woodruff is spangled in white four-petalled stars, rich in nectar and pollen for bees and other insects. May is celebrated in Germany with sprigs of woodruff steeped in white wine punch to make Maibowle. Until then, I keep a bowl of woodruff leaves on my desk, scrunching them between my fingers to release their haytime scent.
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