Aulden Farm - National Collection of Siberian Irises - Iris sibirica Proprietors: Jill and Alun Whitehead http://www.auldenfarm.co.uk

East Of Eden Nursery - Geum Specialist - Proprietor: Roger Proud https://east-of-eden-nursery.co.uk Ainstable, Carlisle, Cumbria, U.K.

The National Collection of Pelargoniums https://www.fibrex.co.uk

Roseland House Nursery - National collection of Clematis viticella Proprietors: Charlie & Liz Pridham http://www.roselandhouse.co.uk Roseland House, Chacewater, Truro, Cornwall, U.K.

Staddon Farm Nurseries (Penny's Primulas) - National Collection of Primula sieboldii Japanese cultivars Proprietors: Penny & Melvyn Jones https://www.pennysprimulas.co.uk