I think I’ve got a photo of Isiatris tinctoria for just about the entire season. Its common name is woad and I usually describe it to non-gardeners as the plant that was used in Braveheart to make the guys blue. One of the neat things about it is that when you remove the seeds (which you should do because it can be invasive), it will stain your hands a lovely blue color which takes a couple of days to come off.
Isatis tinctoria makes for a decent Blue Monday. (Can we make that a thing or is New Order on the downswing with the Brooklyn set?) While woad was a super-important dye not only for warriors in western Europe, but for textiles going all the way back to ancient Egypt, it fell by the wayside with the arrival of Indian indigo (same chemical, just more potent).
The commercial woad industry collapsed a long time back, but there’s a novel equation that’s pushing it back into vogue in small ways: Internet + Bespoke Crafts = Resurgence. Anyone out there worked with woad before?