The Fern-leaf Peony, aka Paeonia tenuifolia, is a very unique but well-known and popular perennial. It has several forms and has also been used in hybridization.
Due to its relative difficulty or slowness in propagation, the retail price is typically above average for a Peony, but well worth it in my opinion!
Here's to dirt under your nails.
Mark, the coolplantsguy