Last year I purchased a plant at a plant sale. The tag said simply ‘celandine.’ It is flowering now, and its flowers are like yellow poppies. The leaves are attractive and very distinctive—deeply cut margins, kind of like oak leaves. But when I think of celandine, I think of the Cicely Barker flower fairies books from childhood. I am not sure this is the same plant.
You are not alone in experiencing ‘celandine confusion,’ discussed in this article from The Scott Arboretum of Swarthmore College. The confusion rests on the use of that common name to describe a plant that is a Washington State-listed Class B noxious weed in the buttercup family, and two different plants in the poppy family.
If you remember the illustration for “The Song of the Celandine Fairy” depicting ‘the lesser celandine,’ the illustration shows Ficaria verna (also called Ranunculus ficaria). There is also a ‘greater celandine’ fairy in Barker’s books, and that image looks more like Chelidonium majus which is in the poppy family and is a native of Europe. It is a bit harder to tell the difference between Chelidonium and Stylophorum diphyllum. Your plant is most likely one of these. Other common names for Stylophorum are ‘celandine poppy,’ and ‘wood poppy.’ Stylophorum is native to moist woodlands of eastern North America. Here’s what will help you tell one from the other:
According to Andrew Bunting, curator of the Scott Arboretum, “Stylophorum has broader leaves and Chelidonium leaves are more dissected. Also, the flowers are smaller on Chelidonium.” These images from Kathy Purdy’s Cold Climate Gardening blog neatly illustrates the differences in flower and leaf size. Further, when they reach the phase of producing seed pods, the difference is striking.
For additional information about Stylophorum, including suggestions of plant combinations for gardens, see this link from University of Wisconsin-Madison’s Master Gardener Program, and this one from Bruce Crawford, director of Rutgers Gardens, on the plant that launched his career in horticulture.