When the flower petals fall off, they leave hard little bb-sized berries. You can easily harvest these, or let them fall and turn into compost.
Historically, medicinal use of the tree had to do with fixin' "female problems." Chasteberry does indeed seem to regulate the period, so I guess that's why it is referred to as "chaste." Chances were, you weren't pregnant if you were still cycling...and I suppose, in theory, chaste.
For the most part it was cultivated by monks and used for stuff like heart and tummy ailments, and relieving arthritis. The berries are mildly spicy so they were ground up and used as a cheap substitute (in medieval times) for (black) pepper. So the plant is also called "Monk's Pepper."
I have a peppermill ready to try it out/do my Cadfael impression as soon as we can finish off the stuff that came with the purchase.
This is a close-up of flax. Flax too is very pretty and looks delicate, though can take a good
beating, lol...the seeds provide flax oil, which has all those good omega 6 or 3 or whatever nutrients you hear about for lowering the less desirable fatty & cholesterol bits in your blood.
Butterflies also seem to fancy them as well...
Flax does get a bit tall and rangy, though. But for a while, it is pretty.