The Medieval Garden Enclosed—The Garden in Heraldry: “Pluck a red rose from off this thorn…” – The Metropolitan Museum of Art https://www.metmuseum.org/perspectives/medieval-garden-enclosed-garden-in-heraldry
Associate Administrator R. Theo Margelony shares research on the history of the rose as a floral charge.
Factions favoring the House of York, on the other hand, associated the white rose