Huge, perfume-scented blooms in all shades of white, pink, and red open during May on garden peonies. This old-fashioned favorite that has held onto some of its popularity in today's gardens, and with good reason. It is a long-lived, sturdy shrub-like perennial with a show-stopping late spring floral display.
The name "peony" comes from ancient Greek mythology, which says that Zeus turned a physician named Paeon into a peony plant to protect him from a jealous god. Garden peonies are herbaceous (non-woody) perennials, but they act like a shrub with sturdy, attractive green foliage on thick stems. In addition to garden peonies, there are also tree peonies with woody stems and hybrids between the two. There are two common complaints against peonies, but fortunately neither one is cause for great concern. Ants love the nectar that seeps out of the flower buds, so they can be all over the plants during the bloom season. They will not hurt the flowers, but if you bring the flowers inside you should rinse them off to get rid of the ants. Peonies can get a fungal leaf blotch or powdery mildew later in the season, especially in wet summers. These diseases only affect the foliage and do not damage the roots, so while the plants may be less attractive no serious harm is done.
There are countless varieties of peonies, but they can be divided into four main categories based on the structure of the flowers: single, semi-double, double, and double bomb. Single varieties (like 'Krinkled White', pictured below) have just one layer of showy petals surrounding a prominent yellow center with pollen and nectar-producing structures. Semi-double flowers still have this yellow center, but they have more densely layered show petals on the outside ('Cora Louise' is a good example). Double flowers look like a pom-pom, and the pollen and nectar structures may be tucked deep inside or they may not be present at all (see 'Diana Parks', the picture of the top of the post). The double bomb form is like double, but the inner petals are smaller and sometimes a different color ('Gay Paree' at the end of the post is a double bomb).
Common Name: Garden Peony
Scientific Name: Paeonia lactiflora
Notable Varieties: 'Gay Paree' (dark pink outer petals with smaller pink inner petals), 'Red Charm' (dark red), 'Shirley Temple' (densely packed white or pale pink petals with some darker streaks) - there are dozens of options
Light: full sun
Size: 24"-36" tall and wide (depends on variety)
Soil: average moisture, drainage, and nurtient levels; somewhat tolerant of less-than-ideal conditions
Blooms: large, fragrant blooms of white, pink, and red (less often peach and yellow) in May
Other Notes: staking or caging before blooms open can prevent stems falling over; annual fertilizer is very helpful for increasing vigor