Just out of curiosity, I checked Spring Hill's online catalog for a fern leaf. They have a double red P.tenuifolia 'Rubra Plena' for $49.99. About 10 years ago, I ordered the same one for $29.99 and that is how I obtained my single red. Beware of mail order offers unless they are from recognized major peony growers. Not to say they are all to be treated with suspicion but do not take offers at face value. For me, the singles multiply much faster than the doubles so they are more available to be sold to the unsuspecting and it can take two years for them to bloom in order to tell the difference. The foliage is almost identical.