Peony: planting, depth, care and why it does not flower

How to plant a peony so that it flowers for decades: the difference between the groups, the exact planting depth, care through the year, dividing and the most common reasons why it does not flower.

In short: The peony (Paeonia) is a long-lived perennial or shrub that, in the right place, flowers for decades. Herbaceous peonies are planted from September to October so that the red buds are at most 2–3 cm below ground, otherwise they do not flower. They want full sun and nutritious, well-drained soil. They are poisonous to dogs, cats and horses.

Latin name	Paeonia, peony family
Planting	September–October (bare-root), potted plants also in spring
Depth	herbaceous: buds at most 2–3 cm below the surface; woody grafted: graft union about 15 cm below ground
Spacing	around 1 m
Flowering	May–June, depending on group and variety
First flowers	usually in the 2nd–3rd year after planting

A peony is planted once in a lifetime. If you get the place and the depth right, it flowers more every year and in the garden outlives its owners; the RHS counts it among very long-lived perennials. If you get one of the two wrong, the plant produces only leaves for years and does not flower. That is why in this article we concentrate mainly on planting and on why a peony does not flower.

By way of introduction, a correction of a common mistake: a peony is not a bulb. Instead of a bulb it has a bundle of fleshy, carrot-like thickened roots and, on the upper part, the so-called crown, buds from which it shoots in spring.

Herbaceous, tree and Itoh peonies

Group	Height	How it grows	Flowers
herbaceous (mainly P. lactiflora and its hybrids, P. officinalis)	60–100 cm	dies back for winter, shoots from the roots	end of May to June
woody, tree peonies (P. suffruticosa and hybrids)	1–2 m	deciduous shrub, woody branches remain over winter	May, 2–3 weeks earlier than herbaceous
Itoh, intersectional (hybrids of herbaceous and woody)	60–90 cm	dies back for winter like a herbaceous one	June, for a long time, strong stems

Most often cultivars of the Chinese peony (P. lactiflora) are grown. According to botany.cz it is the parent species of most herbaceous peonies, and its cultivars have been bred in Europe since the beginning of the 19th century. The old "cottage" peony from grandmother's garden is usually the double common peony (P. officinalis), which flowers somewhat earlier and has less scent.

By flower shape, single, Japanese (with a conspicuous centre of transformed stamens), semi-double and double are distinguished. Double and heavy flowers need support; single ones usually do not and resist rain more easily. What to combine peonies with in a bed is shown in the article ornamental perennials – plant once, enjoy for years.

Planting a peony step by step

The best time for bare-root peonies is September and October. The soil is still warm, the plant roots before winter and shoots in spring without delay. Peonies in pots can also be planted in spring, just water them regularly in the first summer.

Place. Full sun, at least 6 hours a day. In shade or under trees a peony does not flower and grey mould attacks it more easily. Do not choose a place where another peony used to stand.
Hole. Dig a hole about 40–50 cm wide and deep. Mix the soil with well-rotted compost. Do not use fresh manure.
Drainage. In heavy clay soil add coarse sand. A peony cannot tolerate roots in winter wet.
Depth. Spread out the roots and place the buds so that there are at most 2–3 cm of soil above them, in light sandy soil at most 5 cm. The RHS explicitly gives a maximum of 2.5 cm. Deeper planting is the most common reason why a peony does not flower.
Tree peonies. They are mostly sold grafted. They are planted the opposite way, deep, with the graft union about 15 cm below the surface, so that the scion forms its own roots.
Spacing. Around 1 m from neighbouring plants so that air circulates around them.
Watering. After planting water thoroughly so the soil settles. Then check whether the buds have sunk deeper.

Buy bare-root divisions with at least 3 buds. Smaller divisions root more slowly and flower later. Even a well-planted peony usually does not flower in the first year or sets only a few flowers; it comes fully into flower in the third to fifth year.

Care through the year

Spring

In spring, when the shoots come above ground, add a general-purpose fertiliser around the plant. The RHS gives 70 g per m², that is about a handful. More nitrogen promotes leaves at the expense of flowers. Put a ring support in place straight after shooting, while the stems are low; later it is harder.

Flowering

Cut off faded flowers above the first full leaf so that the plant does not put its strength into seed and so that water does not go mouldy in them. Leave the leaves; until autumn they build up reserves for next year. Ants on the buds do not harm a peony; they only collect the sweet secretions.

Summer

Established peonies have deep roots and do not need regular watering. Water in the first year after planting and in spring drought, when the buds are forming.

Autumn

With herbaceous and Itoh peonies, cut the yellowed foliage to the ground in autumn and take it away from the plot, not to the compost. That lowers the risk of grey mould. Woody peonies are not cut, only dry branches are removed in early spring. Peonies are hardy and need no winter cover. Other autumn jobs are summarised in the article important tips for preparing the garden for winter.

Why a peony does not flower

Cause	How to recognise it	What to do
planted too deep	healthy leaves, no buds, year after year	carefully lift in autumn and replant higher
shade	thin stems, few buds	move to sun in September to October
young or freshly transplanted plant	the first 1–3 years after planting or dividing	wait, do not add extra nitrogen
too much nitrogen	lush dark leaves, few flowers	stop feeding, or use only potassium fertiliser
grey mould (Botrytis)	buds turn brown and dry up, stems blacken at ground level	remove affected parts, clear the foliage in autumn
spring drought or light frost	small buds dry up	water in April and May, cover woody ones in a light frost

Dividing and transplanting

A peony does not like change and never has to be divided. If you want to propagate or transplant a plant, do it in September to October. Carefully dig up the clump with a spade, clean it and divide it with a sharp knife into parts, each with at least 3 buds and several strong roots. Plant the divisions at the same shallow depth as when planting. Allow for them not to flower for 1–2 years.

Cutting for a vase

Cut peonies in the morning, at the soft bud stage, when the bud feels like a marshmallow and shows colour. Do not take more than a third of the stems from one plant and leave at least two leaves on each. In a vase they last roughly a week. Buds can also be wrapped in paper and stored in the fridge for several days.

Is a peony poisonous?

According to the ASPCA, the peony is poisonous to dogs, cats and horses. It contains paeonol and, when eaten, causes vomiting, diarrhoea and lethargy. In people the seeds and roots are the riskiest and may cause digestive upset. So do not leave seed pods where children play, and do not offer the plants to animals. An overview of other poisonous ornamental plants is in the article poisonous ornamental plants.

Frequently asked questions

When should I plant peonies?

Bare-root peonies from September to the end of October. Plants in pots can also be planted in spring, but in the first summer they need regular watering.

How deep should I plant peonies?

Herbaceous peonies so that there are at most 2–3 cm of soil above the red buds. Woody grafted peonies, on the contrary, deep, with the graft union about 15 cm below ground.

Why is my peony not flowering?

Most often it is planted too deep, stands in shade or was recently transplanted. Young plants flower only in the 2nd to 3rd year after planting.

When should I cut peonies?

Herbaceous peonies in autumn, once the foliage turns yellow, down to the ground. Cut faded flowers during summer above the first leaf. Do not shorten woody peonies, just remove dry branches.

Why are there ants on my peonies?

They collect the sweet sap that the buds secrete. They do not harm the peony and it does not need them in order to flower; before cutting for a vase just shake them off the buds.

Is a peony poisonous to cats and dogs?

Yes. The ASPCA lists it as poisonous to dogs, cats and horses; when eaten it causes vomiting and diarrhoea.

Sources

Updated: 27 September 2026

Author: Jana Vránová, the editorial name of the Pěstík.cz team. She writes about the garden, herbs and essential oils. We take safety and dosage data from specialist literature and official sources, which we cite in every article.