Herb
Bee-herb, gladdening-herb — a lemon-scented mint that never quite behaved.
These are associations the community holds, not settled fact — the more a reading is shared, the bolder it sits.
The Greek name melissa means honeybee, and beekeepers rubbed the leaves inside a new hive to encourage a swarm to stay — a practice recorded from antiquity to the nineteenth century, and one that may actually work, since the plant produces compounds resembling bee attractant pheromones. That is a rare case of folk practice and chemistry lining up.
Balm's reputation across medieval and early modern Europe was for gladdening: driving away melancholy, comforting the heart, and making people cheerful. The claim is repeated by everyone from Arab physicians to English herbalists, unusually consistently for something so vague. Carmelite water, a monastic preparation with balm at its centre, was sold in Europe for centuries.
Craft uses it for healing, for comfort after loss, and for love workings of a gentle sort. It grows like the mint it is, taking over a bed if allowed, and smells like a lemon that has been left in the sun. Whether it lifts anyone's mood in a way a clinician would recognise is unestablished; whether people feel better for crushing a leaf is not really in doubt.
Readings practitioners have offered, ordered by how many recognise them. Take what serves, leave the rest.
Carried forward
Nicholas Culpeper, The Complete Herbal (1653)
Culpeper puts balm under Jupiter in Cancer and says it strengthens nature much in all its actions, driving away melancholy and sadness. He is repeating an Arab physician he admired, and says so, which for the period is a decent standard of citation.
Carried forward
European beekeeping practice, classical to nineteenth century
Leaves rubbed inside a new hive to persuade a swarm to settle, and balm planted near the skeps. This is one of the few pieces of practical plant-lore in the Compendium with a plausible mechanism behind it.
Credit what you carry. Much of this comes from living traditions, and some of it from traditions that are closed — held by particular peoples and not offered for general use. Where you know whose practice a reading came from, name them; where you don't, say that too.