Rosy's book: https://www.hardysplants.co.uk/gifts/...

Plant list & Zones
Origanum vulgare
10-5
Origanum Kent Beauty
10-6
Hylotelephium Black Beauty
9-4
Allium Canadense
9-4
Festuca glauca Elijah Blue
8-4
Saxifraga Southside Seedling
9-5
Ballota acetabulosa
10-8