On the Heights

Walking on high ground, as I did this week, takes you back in time. There were sweet violets, newly sprouting nettles in the shelter of walls, brave low-growing dandelions and wind-sculpted hawthorn trees just coming into leaf. Spring comes later, and the growing season is short. But that’s not the only difference.

Plants growing at higher altitudes are different from the same species in the lowlands, and when it comes to medicinal qualities, they are often more powerful. The stresses they have to contend with to survive in harsh conditions cause them to produce more active compounds. The scent of thyme, for example, is produced by a cocktail of aromatic chemicals, and the balance changes the higher you go, although the plant – Thymus vulgaris – is technically the same. One of the most pungent mints is the tiny Corsican mint, Mentha requienii, which doesn’t even look like a mint at all.

And it’s not just the aromatics, though those are perhaps the easiest to get a sense of. If you taste as well as smell, you’ll find that upland nettles have a stronger taste, alpine gentians are more bitter, and so it goes on. Wild herbs in general are often thought to be more useful medicinally than farmed ones, because when you provide plants with optimal conditions, feed them and water them and protect them from pests, you get more quantity but often – in medicinal terms – less quality.

It’s a paradox we have to learn to work with. Plundering herbs from fragile habitats is not sustainable, not in the quantities the affluent west demands. Somehow we have to turn our thinking around when it comes to farming herbs, so that we preserve more of those stress-induced characteristics that are so useful to us.