|Paeonia officinalis is a European peony, the first to bloom in late spring. The flowers are double pompons up to 4 inches across. The foliage remains attractive until fall, disappearing underground entirely for the winter. Many cultivars are available. 'Rubra Plena' has deep green leaflets and large, double, crimson flowers with satiny, ruffled petals.
Peonies are herbaceous perrenials arising from thickened tuberous roots. Largely invisible, hidden underground most of the year, they are quite spectacular when they emerge. In spring, purple divided leaves push through the soil, rapidly unfurling and turning green. The fine foliage is attractive in its own right, the flowers are very showy, coming in three types: single or semi-double, Japanese, with one row of petals and a large center, and highly ruffled double forms. The colors generally range from white, light pink to magenta and red. Plant peony tubers in the fall, 1-2" deep, in well prepared garden beds, with organic matter worked in. They respond well to a yearly fertilization, and addition of bonemeal. It is best to leave them undisturbed, dividing them infrequently.
Botyritus can be a problem during humid spells.
Peonies are one of the longest living hebaceous perrenials often found in older gardens, for once established they will survive neglect. One hundred year old peonies are not uncommon. Tree peonies are woody, deciduous shrubs, coming in a variety of colors, including yellows and purples.