Chrysanthemums: how to choose, pinch out and overwinter them

In short: The chrysanthemum (Chrysanthemum) flowers from September to November and needs a sunny, sheltered spot with well-drained soil. Hardy garden chrysanthemums overwinter outdoors, but potted ball-shaped chrysanthemums from the autumn offer often do not survive frost. Pinching out is necessary for a bushy plant. It is poisonous to dogs, cats and horses.

The chrysanthemum is the last big splash of colour of the season. When asters and dahlias finish flowering, it lights up the bed in white, yellow, bronze, pink and burgundy and lasts until the first stronger frosts. Around All Souls' Day every garden centre has it on offer, but that is exactly where most disappointment begins: a ball-shaped chrysanthemum bought in a pot usually does not survive the winter outdoors.

In this article we explain which type of chrysanthemum to choose depending on what you expect from it, how to plant, pinch out, overwinter and propagate it, and what to do when a dog or cat runs around the garden.

Three different plants under one name

Shops use the word chrysanthemum for groups that are grown quite differently. You need to know the difference before buying.

If you want a plant that will return every year, look for the label garden or hardy chrysanthemum at the garden centre and plant it in spring. Treat a ball-shaped chrysanthemum from the autumn offer more as a long-lasting cut flower in a pot, which you can give a chance but should not count on.

Planting a garden chrysanthemum

The chrysanthemum wants a warm, sunny and sheltered spot. In shade it stretches and flowers little, in a windy place the clumps flop open. The soil should be fertile and above all well-drained. Chrysanthemums are destroyed in winter less by frost than by wet around the roots.

1. Timing: plant from mid-May to early June, once the light frosts have passed. Spring planting gives the plant the whole summer to root; planting flowering plants in autumn ends in death much more often.
2. Soil preparation: work compost into the hole. Lighten heavy clay soil with coarse sand or fine gravel so water drains away in winter.
3. Spacing: 30–45 cm depending on the vigour of the variety. Densely planted clumps dry out poorly and powdery mildew attacks them more easily.
4. Depth: plant at the same depth at which the plant grew in the pot and water thoroughly.
5. Container: for a terrace choose a container at least 30 cm in diameter with drainage holes.

Pinching out: without it the chrysanthemum will be sparse

An untreated chrysanthemum forms a few long stems with flowers at the tips. By pinching out you force it to branch and set many more buds.

1. When the young plant reaches about 20 cm (usually at the start of summer), pinch out the tip of the main shoot above a leaf.
2. Side shoots will come from the leaf axils. As soon as they are 10–15 cm long, pinch out their tips as well.
3. Continue until roughly midsummer, in our conditions until mid-July. Do not pinch later, as you would remove the buds that have already been set.

For taller varieties push several stakes in beside the clump in good time and wind string around them. Once a clump has flopped open after rain, it is usually too late to straighten it.

Watering and feeding

Chrysanthemums need even moisture in summer; in drought they drop their lower leaves and flower less. Water at the roots, in the morning, not on the leaves.

In a bed with compost an organic mulch in spring is usually enough. Feed plants in containers from June with a liquid fertiliser every two weeks. When buds start to form, switch to a fertiliser with a higher potassium content, such as the kind used for tomatoes. Do not overdo nitrogen at this stage: it promotes leaves at the expense of flowers and soft tissues tolerate winter worse.

How to overwinter a chrysanthemum

The procedure differs according to where the plant grows and how hardy it is.

Garden chrysanthemum in a bed

After flowering leave the dry stems standing; they protect the clump and help catch snow. Mound a layer of compost or leaves over the root area and in bare frosts without snow add evergreen branches. Cut the dry stems only in spring, when new shoots come up at ground level. The main enemy is standing water, so on heavy soil consider a raised bed.

Less hardy and potted chrysanthemums

Types that are not fully frost-hardy tolerate about −5 °C for a short time. If you want to save them, proceed as follows:

1. After flowering cut the stems back to roughly 20 cm.
2. Dig up the clump, shake off the soil and remove the remaining leaves. This produces a so-called stool.
3. Put it in a box with slightly moist compost in a bright, frost-free place with a temperature of around 4 °C or more (garage, cellar with a window, cold greenhouse).
4. Only occasionally moisten the compost lightly so the stool does not dry out.
5. In spring plant it back outside, or first take cuttings from it.

You can try planting a potted chrysanthemum in a sheltered spot as early as September, while the soil is warm. Plants in full flower from the end of October no longer have time to root and usually rot. General advice on autumn jobs is summarised in the garden calendar for November.

Propagation by cuttings and seeds

Cuttings

Chrysanthemums are most often propagated by spring cuttings from new shoots. They are exact copies of the parent plant, which is not true of seeds.

1. In spring cut young shoots growing from the base of the clump, 5–7.5 cm long.
2. Remove the lower leaves and insert the cuttings in well-drained compost (seed compost with perlite).
3. Keep them warm and moist under film or in a propagator, not in direct sun.
4. Roots form in roughly 3 weeks. You can tell by the cutting starting to grow.

If you want cuttings sooner, you can move the stool to a greenhouse at 7–10 °C in January, and cuttings are then available by mid-February. How to set up a propagator at home is described in the article cutting boxes and cloning plants.

Summer chrysanthemums from seed

True autumn chrysanthemums are practically not grown from seed at home, as the result does not match the variety. From seed, however, you can easily grow annual relatives which catalogues list under the Latin name Chrysanthemum: the tricolor daisy (Chrysanthemum carinatum) with coloured rings on the petals and the low crown daisy (Chrysanthemum paludosum) for containers and edging.

• Starting indoors: March to April on a windowsill, cover the seeds only lightly.
• Direct sowing in the bed: from the end of April to May, then thin to 20–30 cm.
• They flower in summer; removing faded flower heads extends the flowering.

Pests and diseases

• Aphids suck on the tips of shoots and on the buds. Wash strong colonies off with a jet of water; how to deal with them is described in the article whiteflies, aphids and spider mites.
• Earwigs and capsid bugs nibble and deform flowers and tips.
• Chrysanthemum eelworm causes brown wedge-shaped blotches between the veins of lower leaves, which move upwards. Dispose of affected plants in household waste.
• Powdery mildew appears in a dry summer on densely planted clumps as a white coating. Airiness and watering at the roots help, more in the article powdery mildew.
• Chrysanthemum white rust forms whitish warty pustules on the undersides of the leaves. It is a dangerous disease; remove affected plants entirely and do not compost them.
• Grey mould rots the flowers in a damp autumn; remove faded and damaged flower heads.

Chrysanthemums, animals and sensitive skin

The ASPCA lists chrysanthemums as toxic to dogs, cats and horses. They contain sesquiterpene lactones and pyrethrins, and after eating them vomiting, diarrhoea, drooling, loss of coordination and skin irritation appear. Cats that nibble houseplants should not have access to ball-shaped chrysanthemums on the windowsill or in a bouquet.

In sensitive people the sap from the leaves can irritate the skin. If your hands turn red when cutting and pinching out, work in gloves.

Frequently asked questions

Is the chrysanthemum a perennial?

Garden chrysanthemums ("November flowers") are perennials and overwinter outdoors on well-drained soil. Ball-shaped potted chrysanthemums from the autumn offer are bred for a single season and mostly do not survive winter outdoors.

How do I overwinter a chrysanthemum in a pot?

After flowering cut it back to 20 cm and put it in a bright, frost-free room at around 4 °C. Keep the compost only slightly moist. In spring plant it outside or take cuttings from it.

When should I pinch out chrysanthemums?

The first time at a height of about 20 cm at the start of summer, then pinch the side shoots. Stop in mid-July; later you would remove the buds.

Why is my chrysanthemum not flowering?

The chrysanthemum flowers once the days get shorter. Late pinching, shade, overfeeding with nitrogen or all-night lighting from a lamp can delay or reduce flowering. Plants in a cold, shady place often do not manage to flower before the frosts.

Are chrysanthemums poisonous to cats?

Yes. The ASPCA lists them as toxic to cats, dogs and horses. Poisoning shows mainly as vomiting, diarrhoea, drooling and loss of coordination; if you suspect it, contact a vet.

When should I plant chrysanthemums in the garden?

Best in spring, from mid-May to early June. The plant roots before autumn and survives its first winter better than a flowering chrysanthemum planted in October.

Recommended products

• Tricolor daisy – mix (Chrysanthemum carinatum) – an annual chrysanthemum that you can grow from seed in one season.
• Crown daisy (Chrysanthemum paludosum) – a low white chrysanthemum from seed for containers and edging.
• Hoštické fertiliser for TOMATOES and PEPPERS 1 kg – a fertiliser with a higher potassium content for the period when buds are being set.
• Bamboo cane 90 cm, 25 pcs – a support for tall garden chrysanthemums before the clump flops open.
• Premium perlite Gramoflor, 1 l – for cutting compost and for lightening the soil in containers.

Sources

• Royal Horticultural Society: How to grow chrysanthemums
• ASPCA Animal Poison Control: Chrysanthemum

Updated: 27 September 2026