The peonies we see today with their large ball shaped flowers are the result of years of hard work by plant breeders. Peonies have been grown since the Middle Ages and this article by James Sagmiller which I found on his Heirloom Gardener website explains how these flowers have developed over the years into those we grow today.
Two main types of peonies are commonly grown in gardens: herbaceous peonies and tree peonies.? Herbaceous peonies die to the ground every winter and regrow in spring.? Tree peonies are shrubs; their flowers bloom early in spring on woody branches.? Today we will discuss the herbaceous, perennial peonies whose flowers appear in early summer.
Several species of peonies exist.? One of the first grown in gardens was European, Paeonia officionalis (the Memorial Day Peony). ?The single form, with five petals, was grown in the Middle Ages.? Thomas Jefferson grew the double form in his garden.? In the early 19th century several garden forms of the species Paeonia lactiflora arrived in Europe from China and Siberia.? French nurserymen hybridized these with P. officionalis to develop new varieties.? Several are grown today as valuable heirlooms, such as ?Duchesse de Nemours?, from 1856.? In the 20th century America became the center of hybridization for peonies; now hundreds of cultivars are available.
Herbaceous peonies are quite hardy, to USDA climate zone 2. ?The long-stemmed, large flowers are excellent cut.? Three basic flower forms of peonies include: single or semi-doubles with one or two rows of petals; Japanese, with five petals and large stamenoids; and double flowers with many petals. ?Older hybrids come in red, pink, coral, mauve, white and cream.
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