Question to the Department for Environment, Food and Rural Affairs:

To ask the Secretary of State for Environment, Food and Rural Affairs, whether he has made an assessment of the potential impact of mini forests on (a) improving (i) air quality and (ii) diversity and (b) supporting the UK’s environmental goals.

Defra, through the Trees Outside Woodlands research programme (funded by the Government), has carried out a study on the Miyawaki Method of planting, sometimes known as tiny or mini forests. The testing has been carried out since 2021. The long-term potential effects of this type of planting compared to typical planting is not yet known, but the study found that the plots that used the Miyawaki Method produced significantly higher early growth and survival rates. It also found early indications that biodiversity levels may be higher than typical planting. Ongoing research aims to understand the carbon implications and longer-term effects of using the method, but these early findings show that the method is a useful tool that can be deployed for tree planting, particularly in urban areas.

A report on the findings after two years of growth can be found here.