The new building sits at the centre of a multi-million pound development programme, on which work started in April last year. The project is designed to upgrade the visitor facilities and expand the grounds and plant collection by 10 per cent.
The new entrance building combines visitor centre, garden centre, gift shop, cafe and restaurant and garden terrace.
The arboretum is also being expanded by 3ha under director Stuart Priest. The extension will allow more than 500 new trees and shrubs to be added to the collection over the next five years, including Acer, Xanthocyparis vietnamensis, Populus wilsonii and Cercidiphyllum japonicum.