Taking stock of our gardens
Christopher Bailes, Curator of RHS Garden Rosemoor, Devon, is leading a study to gauge the environmental impacts of running the Society’s four gardens.
We have been able to show big reductions since 2001 in the use of materials with the biggest impacts, such as peat, and pesticides and herbicides,’ he says. ‘There is a lot of biological pest control being used along with plant tonics such as compost tea - we’ve seen a 66 percent reduction in chemical use in the last five years.’
Most parts of the RHS gardens get little or no regular fertiliser; the emphasis is on organic materials. Composting is a core part of soil husbandry: ‘We’re aiming for a closed loop where just about everything we take out of the soil finds its way back in’.
At RHS Garden Wisley, Surrey, water extraction has been reduced by 40 percent - The Glasshouse and surrounding structures were designed with water collection and recycling in mind, and the lake acts as a reservoir for the whole garden. The Glasshouse is also far more energy efficient than its predecessor, thanks to its double-glazed cladding and modern computerised climate controls.
‘Different styles of planting also reduce our need for water,’ says Christopher.
A reservoir at RHS Garden Hyde Hall, in dry East Anglia, is fed by drainage and water harvesting that makes the garden just about self sufficient. At RHS Garden Harlow Carr, North Yorkshire a water harvesting system is being put in that will make it 70 percent self-sufficient.
‘Like other big public gardens, one of our biggest changes has been to reduce mowing, both to cut our energy use and improve biodiversity,’ says Christopher. ‘At Rosemoor we have doubled the proportion of grass area maintained as meadow.’