RHS head of science Roger Williams said the Deers Farm twin wall polycarbonate field research facility would be used to study pests and diseases. The structure could be open by late 2011 after a 20-week build, subject to planning permission and fundraising.
Williams said the building would not be accessible to the public because scientists would be dealing with pests and diseases.
He added: "Our members are often unaware of what we do. There is a lot happening at Reading University and Imperial College but there are inadequate facilities at Wisley." He said the RHS wanted to spot new pests and diseases first but needed to do the research to confirm what they were.
The society has 44 scientists. Williams asked 31 organisations what they should be doing for science and the environment and the five areas recommended were biodiversity, climate change-adapting gardens, plant conservation, managing resources (water and peat) and urban greening.