So much I love here (busy nuns! soapwort marginalia! medieval people kept clean!), but the plant was called "saponaria" not "saponifera". Soapwort was used for washing, but real soap was made in many medieval homes, and imported in large quantities and many varieties.
Noa & Una’s Marginalia 📜 Soapwort In the Middle Ages, soap wasn’t something that could be mass-produced like it is today. So what if you wanted to wash your hands but felt that water alone wasn’t enough? That’s where “soapwort” came in! full article below! medium.com/@SisterNoa20...