edewitt
I grow all kinds of peonies - species, herbaceous and woody. I don’t have any true fern leaf tho.
I agree with you wholeheartedly that they are pretty pricey for the true species and plus the true species has specific needs-requires very sharp drainage etc. However there are a good number of fern leaf hybrids that are super early/short with brilliant red flowers/ and with just slightly coarser foliage and they can be had at a much more reasonable price plus they are easier to grow - not as fussy. That’s what I grow.
The most economical way tho would be to buy seeds from the American Peony Society during their annual seed sale. They offer many different species and varieties and the packets of seeds are donated from peony breeders/specialists/members etc. The packets of seed are only 3 $!
This year I planted pink and red fern leaf peony seeds as well as many other types because that is an affordable experiment!
Solaris Peonies and Adelman peonies are both probably the most economical places to get fern leaf peonies if you do want to splurge. Nate Bremer of Solaris in particular has been working on breeding several very fine strains of fern leaf peonies