I've talked about Barbara Cooney's books before (she illustrated Roxaboxen) but I was finally able to get my hands on a copy of Miss Rumphius, a highly regarded book she wrote and illustrated.
The narrator is Alice, the great-niece of Miss Rumphius or Miss Lupine, as she is sometimes known. Alice tells us that Miss Rumphius grew up in a city and was an artist, like her grandfather. Miss Rumphius' grandfather tells her that she must do something to make the world more beautiful.
Miss Rumphius grows up and becomes a librarian and then decides to travel the world. She meets many new friends and sees the beauty of the world. Eventually, she settles down in a little house by the sea and plants lupine flowers in the rocky soil.
(I looked up lupines and the remind me of delphiniums. I think they may be related.)
An old back injury keeps Miss Rumphius from planting more flowers, but once she recovers she is delighted to see that the wind and birds have spread the seeds for her. Now she knows what she must do to make the world more beautiful!
Eventually, the whole town has lupines sprouting up and the people start to call her Miss Lupine. She remains kind and tells Alice and her friends stories of her travels.
Of course, she challenges the children to do something to make the world more beautiful.