How do I grow peonies?
Herbaceous peonies only grow in cool climates with cold winters such as Tasmania, Victoria and mountain districts – they need cold to help trigger the development of the flower bud. Tree peonies also prefer cold climates but will also grow in cool temperate areas.
Position herbaceous and tree peonies in full sun and shelter from strong winds. In climates with hot summers, a lightly shaded spot is preferable.
Plant in deep, moist and well-drained soil enriched with well-rotted compost and manure. A neutral soil pH is desired by herbaceous peonies but tree peonies prefer a more alkaline soil, so add dolomite lime and fork in well before planting.
Keep soil moist, but never wet. In summer, water to keep soil cool and ensure it doesn’t dry out. Once established (1–2 years), tree peonies are quite drought tolerant, but benefit from regular watering throughout the growing and flowering season.
In late winter, feed herbaceous peonies with a well-balanced fertiliser and remove surrounding weeds. Apply fertiliser again in summer after peonies have finished flowering and you have deadheaded. For tree peonies, feed in winter and late spring with a fertiliser low in nitrogen but high in phosphorus and potassium. This will help encourage strong root growth and flowering.
While it is possible to transplant peonies, generally speaking they don’t like to be disturbed, so choose your location carefully. Prepare the soil by incorporating well-rotted compost and manure (and dolomite lime, if needed) a week prior to planting.
Types of peony
Herbaceous peonies are sold as bare root rhizomes with a few buds or ‘eyes’ and are best planted in autumn. Dig a shallow hole no more than 5cm deep and firm the base of the hole. Position rhizomes with buds facing upward, backfill and lightly firm soil, then water thoroughly. Plant at least 60cm apart – they like a little space between plants.
This perennial is slow growing, but eventually forms a substantial bush about 90H by 50cmW. The stems retreat in winter.
More of a shrub than a tree because of its multiple stems. The tree peony grows to more than 2m and has a big visual impact. Plant as a specimen in your garden,
to give it room to spread and let its blooms shine without competition
As herbaceous peonies grow, use a three-legged metal wire frame to help support the stems. Look for them at your local garden centre. Don’t be surprised if there are few or no flowers in the first year – the plant is still developing and will flower once it grows into a healthy bush. In late autumn, allow foliage to naturally die down before pruning. When the bush flowers, cut long stems for indoor display or deadhead regularly as flowers fade to encourage more blooms.
Tree peonies only need pruning to remove dead or broken branches – they should only be pruned as the growing season starts. Apply a generous dose of dolomite lime to the soil every three years and water in well.
A hybrid of the herbaceous and tree peonies, the huge blooms flower over a longer period. It has the foliage of the tree peony but dies back to the ground like a herbaceous peony in winter. Its petals are often two-toned.
How to grow herbaceous peonies
A bit of care in a peony’s early days means you can sit back and admire it in the years to follow – a period that can go for 80-100 years.
A long, cold winter with regular, settled frosts.
The roots don’t like being disturbed, so start with bare roots in autumn. Dig a hole
60 x 60cm and make a soil mound at the base 2-4cm below the garden surface. Place on the mound with the eyes, or buds, facing up. Backfill, lightly press down soil and water in. If the roots look dry, soak overnight.
An open north or east spot with exposure to morning spring sun and full summer sun to help buds develop and open into blooms. Protect from strong winds.
Well-drained, alkaline and rich in nutrients. If necessary, dig in organic matter before you plant.
Lots of water in summer but they hate wet feet, so if your soil can’t drain the water, grow in a raised bed or large container. As they mature, they become reasonably drought resistant but need regular watering during their first summer and during long, hot, dry periods.
Don’t fertilise in spring or you risk burning new growth. Instead, give a well-balanced feed in late winter and in summer after the flowers have gone.
The stems naturally retreat in winter but cut back those that linger so it bounces
back in spring.
Herbaceous vs tree peony
Herbaceous peonies, also known as Chinese peonies (Paeonia lactiflora), are the most commonly grown. They grow from rhizomes, which form a bush about 1m high and flower from late spring into summer, before dying down in autumn. Tree peonies (Paeonia suffruticosa), are a shrubby deciduous plant that grows about 1m tall. They can take up to 10 years to reach full height and do not die down like their herbaceous cousins. Both types of peonies prefer cool to cold climates.
Types of blooms
Simple and elegant, this bloom features a single row of petals surrounding a rich circle of stamens.
The multiple rows of voluptuous, ruffled petals make these the most popular peony blooms in Australia.
Similar to doubles, but the stamens and carpels are still distinctive and remain at the centre after the bloom fades.