One of my favorite parts of drawing garden subjects is the unexpected discovery of some startling bit of botanical history — a story that pops up like an unexpected seedling and demands to be shared. It happened recently during preparation for my online course, The Heirloom Garden in Colored Pencil. A strange story about rhododendrons wrapped its roots around my imagination and wouldn’t let go.
Rhododendrons (and their popular relative, azaleas) produce pollen that contains a small amount of potent neurotoxin. Called grayanotoxin, it’s not harmful under ordinary circumstances… but occasionally, when concentrated by honeybees as they make rhododendron honey, it can cause a nasty illness marked by hallucinations and digestive distress. Although rare today — the most recent US cases on record happened in Seattle in 2011 — “mad honey disease” has a special place in history.
A clever first-century general defeated an entire invading army by putting grayanotoxin to work. During a battle in the Black Sea region in 67 BC, Pompey ordered his troops to leave honeycomb laced with “mad honey” along the path of approaching Roman soldiers. The hungry invaders took the bait. Sickened and disoriented, the Romans were no match for the waiting enemy.
The rhododendron, then, is much more than just a pretty face. Grow them, celebrate their history… but don’t put your beehives too close by.