Common Name: tree peony
Botanical Name: Paeonia suffruticosa
Form: graceful vase shape
Plant Type: deciduous, woody shrub
Mature Size: 3 – 5 ft x 3 -4 ft
Origin: China, Tibet
Hardiness Zones: 5 to 9
Foliage: attractive matte green foliage made of deeply divided leaflets
Flowers: huge 6 to 8 inch flowers with satin-like petals in reds, pinks, white and prominent bright yellow stamens
Fruit: large seed pods that resemble crowns
Exposure: sun to part shade
Soil: rich moist soil that drains well
Uses: specimen, borders, accent, background
Pruning: little needed, just remove dead growth and any suckers that arise from the roots
Problems: not common: canker, leaf blight, scale (ants on the buds cause no harm so leave them be)
Tree peonies are cousins of garden peonies, however, they are not herbaceous. Like their name suggests, tree peonies do not die down for winter. As they age, they reach 5 feet at maturity and to a width of 5 feet. Compared to their lesser cousins, their huge magnificent blossoms flower about 3 weeks earlier and are much, much larger. Both types of peonies benefit from deadheading as soon as their flowers have died.
Plant in fall or early spring as summer is just too hot and dry. They benefit from a rich soil so add leafmould, compost or well-rotted manure. Keep soil moist and water during drought. Many tree peonies are grafted onto a rootstock. Remove any shoots (suckers) that emerge from the roots. Mulch the soil around it, but don’t cover the stems. It takes up to 4 years for newly planted tree peonies to flower so be patient. Too much shade also inhibits flowering. Plant at the same depth as it is in the container. If planted to shallow, it may produce suckers and it may fail to flower.
Because the flowers are so large, plants tend to be top heavy when in flower. Stake them when necessary and refrain from planting them in open windy areas.