Impact of diverse plant communities on essential oil levels

An arable farm and an essential oil producer in Scotland are exploring whether plants grown in biodiverse farming systems produce higher levels and a greater diversity of essential oil compounds than those grown in intensive arable settings.

The field lab will test the hypothesis that plants exposed to more complex, competitive and environmentally stimulating conditions invest more energy into producing volatile compounds. These compounds underpin flavour, aroma and therapeutic qualities in crops used for food, herbal medicine, cosmetics and perfumery.

By comparing peppermint grown in species-rich field margins with peppermint grown in intensively managed arable fields, the trial aims to generate practical evidence that could help farmers better understand the economic and ecological value of biodiversity on their farms.

How it works

Plants produce volatile compounds as part of their natural defence and stress-response systems. These compounds are central to essential oil production and play a key role in determining oil yield, aroma profile and commercial value.

It's hypothesised that extensive farming systems that allow a greater diversity of species to share physical space with an agricultural crop (encompassing nature-friendly farming, organic farming and regenerative farming) will produce plants that produce a higher yield and greater diversity of volatile compounds than those grown amongst intensive farming systems that support lower levels of within crop biodiversity.     

This field lab will test whether increasing within-crop biodiversity leads to:

• Higher essential oil yields

• A greater diversity of volatile compounds

• Changes in the abundance of key compounds such as menthol and menthone

Trial Design 

The field lab will compare essential oil production in peppermint grown under two farming environments:

• Biodiverse field margins, sown with a wildflower mix

• Intensively managed arable fields, sown with wheat

Peppermint (Mentha × piperita) has been selected as a model species due to its high essential oil yield and suitability to the site. 

For more information on the trial design please click on the reports tab on the brown banner above.