Tiny amounts of the bacteria mycobacterium vaccae, which is found found in soil that’s been enriched with compost or manure, has been shown to boost serotonin levels in the brain as well as regulate the immune system when inhaled while we garden. The soil is full of other strains of bacteria too. A single teaspoon of garden soil containing around a billion microbes will boost the flora in our gut which in turn is increasingly understood to contribute to our mental health.
Time in the garden might also lift the spirits because of the way our brains have evolved. Our hunter gatherer forebears’ survival depended on their ability to be fully present in the natural environment as they foraged for food whilst looking out for danger. In her book ‘The Well Gardened Mind’ Sue Stuart-Smith convincingly argues that the process of absorbing ourselves in the tending of our gardens in many ways a continuation of this prehistoric mindfulness.
I love the creative process of designing and shaping a garden but I’m not always as enthusiastic about rolling up my sleeves to do the more boring things like weeding or digging over the compost. I know these jobs are just as essential but the added knowledge that these less glamorous activities are also key to my own good health is a very useful motivation for tolerating the tedium.
