" The most potent protection was to employ a charm or potion based on the Anglo-Saxons’ nine sacred herbs, which included several familiar weeds: mugwort, plantain, stime (watercress), maythen (mayweed or chamomile) atterlothe (probably betony) wergulu (stinging nettle), chervil, fennel and crab apple. The fact that weeds might be simultaneously a curse and a benediction wasn’t a cause of confusion. As today, it was a matter of context. In the soil, they were trouble; in the sickroom, a cure. Their ubiquitousness and obstinate power in the fields may even have strengthened their healing image. "

― Richard Mabey , Weeds: How Vagabond Plants Gatecrashed Civilisation and Changed the Way We Think About Nature