I first saw Sheffield daisies at the Smith College perennial garden. It was late in the fall and I was amazed and delighted by this large clump of gloriously blooming pink flowers. I had no idea what they were, and posted the picture with a query to my readers. The answer was quick in coming - Sheffield daisies, also called Sheffies. They are strong growers and very hardy. They came through last week's frost untouched. I have grown…