Arnica is a gardener’s best friend; it heals bruises and sprains – and insects love it. Best used as a medicated oil or poultice on areas of pain from inflammed muscles and joints. It should never be used on broken skin or taken internally. Arnica chamissonis – or ‘meadow arnica’ – is native to America and not to be confused with the official ‘medical’ species, Arnica montana – or ‘mountain arnica’, which is native to Europe. Both have similar properties, but meadow arnica is much easier to grow and more abundant than its European cousin, which is now listed in the IUCN Red List of threatened species as a result of over-harvesting. Given a sunny position and rich loamy soil, it will start producing flowers in its first year, and by the second year will be thick carpet of yellow that is much loved by butterflies.