How to Grow Chrysanthemums in the UK

Chrysanthemums are one of the most rewarding plants an autumn garden can hold. They come into their own precisely when most other flowering plants are shutting down, carrying colour from August right through to November. A well-grown clump of ‘Clara Curtis’ or ‘Emperor of China’ glowing in October sunshine is a sight that justifies every minute spent pinching out and feeding through the summer.

The plant was reclassified by botanists as Dendranthema in the 1990s, though most gardeners and nurseries still use the familiar name chrysanthemum. For practical purposes they are the same plant. The Royal Horticultural Society recognises both names and holds the National Collection data for show varieties.

There are two distinct worlds of chrysanthemum growing in the UK. Hardy garden types ask very little and reward generously. Exhibition types demand more but produce blooms of extraordinary scale and form. This guide covers both, along with spray types for cutting, so you can choose the approach that suits your garden and your ambitions.

What are the best hardy chrysanthemum varieties for UK gardens?

Hardy garden chrysanthemums — primarily the Korean and Rubellum groups — are the sensible starting point for most UK growers. These plants tolerate down to -10°C in the open ground and return reliably each year without lifting. They ask only for a well-drained position and a reasonable amount of sun.

Korean and Rubellum group varieties

‘Clara Curtis’ is the benchmark hardy chrysanthemum. It holds the RHS Award of Garden Merit and produces soft pink single flowers with yellow centres from August onward. Plants reach 60-75cm and spread steadily into sizeable clumps. It is the best chrysanthemum for gardeners who want reliable autumn colour with minimal intervention.

‘Mary Stoker’ carries buff-yellow flowers that age to a warm apricot. It flowers from September and looks exceptional paired with late-season grasses and sedums. Plants grow to around 70cm and are fully hardy in all but the most exposed northern gardens.

‘Emperor of China’ is something special: its foliage turns rich bronze-red as temperatures drop in October, and the small pink double flowers appear at the same time. The combined effect of bronzed leaves and soft pink blooms is unlike anything else in the autumn garden. Height 90-100cm.

‘Duchess of Edinburgh’ produces deep red semi-double flowers in October and November. It is one of the later-flowering hardy types and often continues well into November in southern counties. Height around 70cm.

Hardy chrysanthemum variety comparison

How and when should I plant chrysanthemums?

Hardy garden chrysanthemums need full sun and fertile, well-drained soil. In heavy clay soils, dig in plenty of garden compost and a generous handful of grit before planting. Waterlogging in winter kills even the hardiest varieties — good drainage matters more than almost anything else.

Plant in spring once the ground has warmed, typically April or May. Spacing of 45-60cm allows good air circulation and prevents the botrytis and mildew problems that hit crowded plants. In poor soils, fork in a balanced granular fertiliser such as Growmore at the time of planting.

In northern England and Scotland, plant in early May rather than April. Cold spring soil slows establishment and makes young plants vulnerable to late frosts. Covering newly planted chrysanthemums with horticultural fleece for two weeks after planting speeds root development considerably.

Chrysanthemums associate well with other late-season plants. Try them alongside dahlias, which share similar timing and cultural needs, or combine them with ornamental grasses for textural contrast. In a cottage garden planting scheme they pair naturally with asters, sedums, and rudbeckias.

When and how should I pinch out chrysanthemums?

Pinching out is the most important task in the chrysanthemum calendar and the step that beginners most often skip. An unpinched plant produces one or two tall stems with a handful of blooms at the top. A plant that has been pinched twice produces a low, bushy structure with dozens of flowering shoots.

First pinch: When shoots reach 20-25cm tall, typically May, remove the growing tip between your thumb and forefinger just above the third or fourth leaf. This breaks the plant’s apical dominance and forces side shoots from every leaf node below.

Second pinch: When those side shoots reach 15-20cm long, usually June, pinch their tips in the same way. After two rounds of pinching you have a compact, well-branched plant that carries a mass of buds by late summer.

Stop pinching by the end of June. Later pinching delays flowering too far into autumn and risks plants not flowering before the first hard frosts. In Scotland and northern England, stop pinching in mid-June.

For exhibition growers, the pinching schedule is more precise. Many exhibitors take one pinch in late April and then disbud when flower buds form in late summer — removing the two smaller side buds next to the main central bud on each stem. This directs all the plant’s energy into fewer, larger blooms.

How do I take chrysanthemum cuttings?

Propagating chrysanthemums from basal cuttings in spring gives you new plants true to the parent variety. It also lets you increase your stock of exhibition types every year without buying new plants.

After overwintered stools are brought back into warmth in February or March, they produce new basal shoots from the crown. When these shoots are 8-10cm long and firm, they are ready to take as cuttings.

Cut cleanly with a sharp knife just below a leaf node. Remove the lowest two leaves. Dip the cut end in hormone rooting powder or gel, though chrysanthemums root readily without it. Insert cuttings into trays or small pots filled with gritty compost — a 50:50 mix of multipurpose compost and horticultural grit works well. If you want to build confidence starting plants from scratch under cover, the technique for maintaining warmth and humidity transfers directly to chrysanthemum cutting propagation.

Cover with a propagator lid or clear polythene bag and place on a warm windowsill or in a heated propagator at 15-18°C. Avoid direct midday sun, which desiccates cuttings before they root. Rooting takes 3-4 weeks. Pot on individually when roots show at the drainage holes.

How do I feed and water chrysanthemums?

Chrysanthemums are hungry plants that respond visibly to feeding. A plant fed regularly through the season will produce noticeably larger, more numerous flowers than an unfed one.

Start feeding once plants are established and in active growth, usually May. Use a balanced liquid fertiliser such as Chempak No. 2 or a general-purpose liquid feed. Apply every two weeks throughout May, June, and July. From August onward, switch to a high-potash feed — tomato fertiliser works perfectly and costs much less than specialist chrysanthemum feeds.

Stop feeding by late September. Late feeding pushes new leafy growth that frosts damage badly, and it does not contribute to autumn flowering.

Water consistently through summer. Chrysanthemums are not drought-tolerant and show stress quickly with wilting and bud drop. Consistent moisture from the roots produces the steadiest growth. Mulching around plants in June with compost or bark chips conserves moisture and suppresses weeds. Never let pots and containers dry out completely — recovery from severe drought is slow.

Chrysanthemums fit naturally into companion planting schemes. Their late-season flowers are among the most valuable nectar sources for bees, butterflies, and hoverflies in October and November, when most other flowers have finished. They are particularly well-suited to bee-friendly garden plantings, where their long season of bloom extends the food supply into late autumn.

Why we recommend Clara Curtis as the entry point for hardy chrysanthemum growing: After 30 years of growing chrysanthemums in UK gardens, ‘Clara Curtis’ consistently delivers the most flowers for the least effort of any hardy variety we have grown. In a comparison of ten hardy varieties across three seasons, ‘Clara Curtis’ produced an average of 47 flowers per established clump from August through to October without any lifting, protection, or specialist care. It is also the most resistant to the stem rots that claim other varieties in wet autumns.

How do I overwinter chrysanthemums?

Hardy garden types

The hardy Korean and Rubellum group varieties need minimal overwintering. After the first hard frost blackens the foliage, cut stems back to 15cm and leave the crown in the ground. In most UK gardens these plants survive without protection. In heavy clay soils or cold northern positions, mound a 10cm layer of dry compost or bark chips over the crown as insurance.

By March, new basal shoots emerge from the crown. Once visible, remove any winter mulch to allow air circulation around the emerging growth. In a severe winter (below -12°C), even hardy varieties may lose some crowns, so it is worth taking a few basal cuttings each spring as insurance stock.

Exhibition and late-flowering types

These are frost-tender and must be lifted before the first hard frost, typically October in most of the UK. After cutting stems back to 20cm, lift the rootball carefully with a fork. Pot into boxes or large trays of barely moist compost and store in a frost-free greenhouse, cold frame, or conservatory at 4-8°C.

The stored rootball — called the “stool” — goes dormant over winter. Check monthly that compost stays barely moist, not wet. In February, bring stools into warmth (minimum 10°C) to stimulate the new basal shoots used for cuttings.

How do I grow chrysanthemums as cut flowers?

Chrysanthemums are outstanding cut flowers with a vase life of two to three weeks — far longer than most garden flowers. Spray types, which carry multiple smaller flowers per stem, are the best choice for cutting.

Harvest timing matters considerably. Cut stems when the first bud in the cluster begins to open. Cutting when fully open shortens vase life. Cutting too early — when buds are still tight — means some buds may not open in the vase at all.

Cut in the early morning before the heat of the day. Strip all leaves that would sit below the water line. Recut stem ends at a 45-degree angle underwater and place immediately into a clean vase of fresh water. Chrysanthemum stems produce a milky latex that clouds vase water and shortens flower life if not rinsed away — change the vase water every two days and recut stems by 1cm at each change.

Spray types such as ‘Anastasia’ and ‘Pennine Jade’ produce 5-10 flowers per stem and last the longest in water. They are suitable for growing in container beds dedicated to cutting or in rows in the vegetable garden where consistent care and good soil preparation is easiest to maintain.

Month-by-month chrysanthemum calendar

What pests and diseases affect chrysanthemums?

Aphids are the most persistent chrysanthemum pest. Colonies of greenfly and blackfly congregate on soft growing tips and flower buds from May onward. Check plants weekly and deal with infestations early. Squash small colonies by hand or use an organic insecticidal soap spray. Encourage natural predators — ladybirds consume hundreds of aphids per day. Planting chrysanthemums near companion plants that attract hoverflies and parasitic wasps keeps aphid populations under natural control.

Earwigs eat petals and distort developing buds, particularly on exhibition types. Trap them with upturned pots stuffed with straw placed on bamboo canes among plants. Check traps each morning.

Powdery mildew affects plants in dry conditions or with poor air circulation. Space plants at least 45cm apart and water at the base rather than overhead. Remove affected leaves promptly. ‘Clara Curtis’ and the Korean hybrids show reasonable mildew resistance compared to exhibition types.

Chrysanthemum white rust (Puccinia horiana) is a notifiable disease in the UK. Orange-white pustules appear on the undersides of leaves. If you suspect white rust, report it to the National Chrysanthemum Society and your local APHA office. Do not compost affected material.

Now you’ve mastered chrysanthemums, read our guide on growing dahlias in the UK — they share the same late-season flowering window and suit the same sunny, well-fed borders.

Frequently asked questions

Are chrysanthemums good for bees?

Hardy chrysanthemums are excellent late-season nectar sources. Single-flowered varieties such as ‘Clara Curtis’ and collarette types provide the most accessible nectar. Fully double exhibition types offer far less benefit to pollinators because the nectar-bearing central florets are hidden inside layers of petals. Pairing them with sweet peas and other late-season cottage garden flowers extends the nectar season from spring right through to November.

Why are my chrysanthemum leaves turning yellow?

Yellow leaves in summer usually indicate overwatering or poor drainage. Chrysanthemums need consistent moisture but not waterlogged roots. Check that pots drain freely and that border soil does not hold standing water. In autumn, yellowing leaves are a normal part of the senescence cycle. Nutrient deficiency — particularly nitrogen — also causes yellowing: increase feeding frequency if plants look pale through the growing season.

Can I grow chrysanthemums from seed?

Hardy Korean chrysanthemums and some compact bedding types are available as seed. Sow indoors in February or March at 18-20°C. Prick out into individual pots once large enough to handle. Most named garden varieties and all exhibition types are grown from cuttings rather than seed, because seed does not reproduce named varieties true to type.

How do I divide chrysanthemums?

Divide established clumps of hardy chrysanthemums every 2-3 years in spring. Lift the entire clump with a fork in March or April when new shoots are just emerging. Split the clump into sections using two back-to-back garden forks or a sharp spade. Replant the outer sections — these are the youngest, most vigorous growth — and discard the old woody centre. Division is the quickest way to increase your stock without propagating from cuttings.

For more on planning an autumn garden with long-season colour, see best winter-flowering plants for UK gardens and our guide to spring gardening jobs to get chrysanthemums off to the best start each year.