Paeonia lactiflora 'Calypso' (Peony) — Clump-forming, upright

Overview

Paeonia lactiflora 'Calypso' is a clump-forming, upright perennial in the genus Paeonia, part of the Paeoniaceae family, with deciduous; deeply divided, frequently bronze-flushed when young foliage. It typically grows around 0.8 m tall. Paeonia lactiflora 'Calypso' grows best in full sun to partial shade, and tolerates deep and fertile loam or clay soils and neutral to slightly alkaline pH. Its UK hardiness is rated H6–H7.

About

Paeonia lactiflora 'Calypso' is an upright, clump-forming herbaceous perennial peony reaching about 0.8 m, notable for its bronze-flushed young foliage and spring blooms. Leaves are deeply divided and often bronze when young, later turning green. It flowers in May to June and performs best in full sun to partial shade on deep, fertile loam or clay that remains moist but drains freely. Sit it in a sheltered spot and avoid exposing frosted buds to early morning sun.

Wikipedia contributors, CC BY-SA 4.0 — Paeonia lactiflora

About the genus

The peony or paeony is any flowering plant in the genus Paeonia, the only genus in the family Paeoniaceae. Peonies are native to Asia, Europe, and Western North America. Scientists differ on the number of species that can be distinguished, ranging from 25 to 40, although the current consensus describes 33 known species.

Wikipedia contributors, "Peony", CC BY-SA 4.0 — Peony

In the garden

Paeonia lactiflora 'Calypso' belongs to the garden peonies derived from Paeonia lactiflora and traces its background to the broader central and eastern Asian peonies cultivated for centuries. As a clump-forming, upright perennial it reaches about 0.8 m and shows deeply divided, deciduous foliage that is frequently bronze-flushed when young. Plant 'Calypso' in full sun to partial shade on deep, fertile loam or clay with a neutral to slightly alkaline pH; keep soil moist but well drained. Give it a sheltered aspect and avoid siting where early morning sun falls on frosted buds, which can damage emerging shoots. Hardiness is H6–H7, meaning it is very hardy to fully hardy and will tolerate winter conditions across most of the UK garden range. Use it towards the middle or rear of herbaceous borders and mixed perennial beds where its 0.8 m height provides structure through late spring. Flowers appear in May to June, and the early bronze-tinged foliage gives season-long interest before and during flowering.

Growing conditions

Best soil and position for Paeonia

Sunlight: Full sun to partial shade
Soil type: Deep, fertile loam or clay
Soil pH: Neutral to slightly alkaline
Soil moisture: Moist but well drained
Aspect: Any but deep shade; avoid early morning sun on frosted buds
Exposure: Sheltered
UK hardiness: H6–H7

Plant details

Paeonia lactiflora 'Calypso' size, habit and characteristics

Plant type: Perennial
Habit: Clump-forming, upright
Foliage: Deciduous; deeply divided, frequently bronze-flushed when young
Height: 0.8 m

Care notes

Pruning and caring for Paeonia lactiflora 'Calypso'

Cultivation: Plant herbaceous peonies with the crown no more than 3cm below the surface — deep planting is the commonest reason a clump never flowers. Enrich the ground thoroughly before planting, then leave undisturbed, and support the heaviest doubles before the buds open.
Pruning: Cut herbaceous stems to ground level once the foliage has died back in autumn and clear the debris away, which reduces the risk of peony wilt. Tree peonies need only dead or crossing wood removed after flowering.
Propagation: Divide herbaceous crowns in late autumn into sections carrying at least three dormant buds with roots attached, and only once flowering begins to decline. Tree peonies are grafted or layered; seed is slow and variable.
Pest resistance: Rarely troubled by pests. Ants on swelling buds are drawn to the nectar and do no harm.
Disease resistance: Susceptible to peony wilt in damp seasons; open spacing and prompt removal of affected growth are the best defence.

Frequently asked questions

How do I grow Paeonia lactiflora 'Calypso'?

Plant herbaceous peonies with the crown no more than 3cm below the surface — deep planting is the commonest reason a clump never flowers. Enrich the ground thoroughly before planting, then leave undisturbed, and support the heaviest doubles before the buds open.

Where is the best place to plant Paeonia lactiflora 'Calypso'?

Paeonia lactiflora 'Calypso' prefers full sun to partial shade. It suits sheltered positions.

What soil does Paeonia lactiflora 'Calypso' need?

Paeonia lactiflora 'Calypso' grows best in deep and fertile loam or clay soil. It prefers neutral to slightly alkaline soil. Aim for soil that stays moist but well drained.

How do I prune Paeonia lactiflora 'Calypso'?

Cut herbaceous stems to ground level once the foliage has died back in autumn and clear the debris away, which reduces the risk of peony wilt. Tree peonies need only dead or crossing wood removed after flowering.

How big does Paeonia lactiflora 'Calypso' grow?

Paeonia lactiflora 'Calypso' reaches a height of 0.8 m.

Is Paeonia lactiflora 'Calypso' hardy in the UK?

Paeonia lactiflora 'Calypso' has an RHS hardiness rating of H6, meaning it is very hardy, tolerating -20 to -15°C across most of the UK.

How do I propagate Paeonia lactiflora 'Calypso'?

Divide herbaceous crowns in late autumn into sections carrying at least three dormant buds with roots attached, and only once flowering begins to decline. Tree peonies are grafted or layered; seed is slow and variable.

More in the Paeonia genus

Browse all Paeonia →