Hollyhock: sowing, planting, caring for

Description and botany

La Hollyhock, Alcea rosea (formerly called Althaea), also sometimes known as Passerose, Stick-rose, Papal rose or primerose, is a short-lived perennial, annual or biennial plant of the family Malvaceae like mallows, lavateras, hibiscus, its close cousins.

Native to temperate regions of Europe and Asia where it grows in rocky places and dry wastelands. It has naturalized in abandoned gardens and fallow land.

The genus comprises about 60 species of hollyhocks of which the most widespread is Alcea rosea. It has given rise to numerous varieties and hybrid series with single or very double flowers (series ‘Chater’s’, ‘Halo’, ‘Simplex’, ‘Spotlight’) and interesting selections in varied colours, such as dwarf hollyhocks ‘Majorette Mixed’ or ‘Summer Carnival’, grown as annuals.

Althaea rugosa, with yellow flowers and leaves covered with hairs, and Alcea ficifolia or the fig-leaved hollyhock, are much less used in gardens. Hybridised with Alcea rosea, the latter appears in shades of pink, red or white, as in the ‘Antwerp Mixed’ selection.

Alcea rosea – botanical illustration

On a taproot, it quickly develops a graceful, bushy clump with an upright habit. From each rosette of rounded leaves emerge sturdy, hairy stems that reach 1 to 2.5 m in height, often exceeding human height.

Leaves are deciduous or semi-evergreen, covered with rough hairs, mid- to pale green or green-grey, up to 18 cm long, rounded with undulate margins, cut into 3 or 7 shallow lobes, sometimes veined. In Alcea ficifolia, they recall fig leaf shape.

They are arranged alternately along unbranched stems.

Hollyhock is recognisable by its sturdy, majestic flowering spikes, always striking in a summer garden. From June to September, on these hairy stems appear countless flowers with a crumpled texture.

These spikes, very dense or more open, are topped by large buds that open progressively from base to tip, into delicate corollas, single, semi-double or fully double in cultivars, 2 to 10 cm in diameter.

Depending on variety, flowers open as wide 5-petalled crinkled cups like hibiscus flowers, or as large ruffled pompons evoking a peony.

Short-lived, these simple, silky flowers with translucent texture last only one day.

They display shades ranging from very soft and warm pastels to intense, even rare tones, from powder-pink, salmon-pink, to yellow, bright red, through garnet red, blackcurrant and the famous ‘black’ of Alcea rosea ‘Nigra’, which is actually very dark violet.

Hollyhocks of the ‘Halo’ series offer large flowers in bicoloured cups trimmed with a lighter halo around a contrasting centre.

Unscented, they are highly melliferous and attract many butterflies, foraging insects and pollinators.

Hollyhocks offer a beautiful diversity of forms and colours

Flowering gives way to numerous capsule fruits filled with small brown, round, flat seeds that self-seed freely.

Hollyhock, hardy to -15°C, is often perennial in southern France where it tolerates drought well, and short-lived in cooler climates where it is commonly grown as a biennial. Easy to grow, while content with ordinary, even poor or stony soils, rather dry and well-drained, it flowers better in rich soil. It requires a sunny location sheltered from wind which can flatten the flowering spikes.

Typical of cottage gardens, hollyhock is often grown at the back of beds, in borders or leaning against a wall. The tall, architectural silhouettes are classics of English and natural-style gardens.

As attractive as it is tasty, hollyhock is an edible plant; its flower buds can be eaten raw in salads and its young leaves raw in salads or cooked as a purée.

An oil with soothing properties is extracted from its seeds.

Main species and varieties

Most popular

Our favourites

Alcea rosea Nigra - Hollyhock

A must-have in cottage gardens with a unique, dark, almost black shade. It's a fairly short-lived perennial but extremely hardy.

• Flowering time August to October
• Height at maturity 2 m

See the product sheet

Alcea rosea Mars Magic - Hollyhock

A recent variety belonging to the 'Spotlight' series, producing vigorous perennials with pure colours. It self-seeds spontaneously in the most unexpected corners of the garden.

• Flowering time August, September
• Height at maturity 1,80 m

See the product sheet

Alcea rosea Halo Blossom - Hollyhock

A hollyhock from the Halo series with large single corollas, white, marked with a superb dark crimson centre. Irreplaceable in cottage gardens!

• Flowering time August to October
• Height at maturity 1,50 m

See the product sheet

Alcea rosea 'Simplex'

This simple version is the quintessence of the hollyhock! This classic variety is timeless and perfect at the back of a border.

• Flowering time July to November
• Height at maturity 1,80 m

See the product sheet

Alcea rosea Chaters Double Rose - Hollyhock

A delightfully romantic hollyhock with large very double flowers. Magnificent against a wall or leaning against a conifer hedge.

• Flowering time August to October
• Height at maturity 2,20 m

See the product sheet

Alcea rosea Chaters Double Jaune - Hollyhock

We love its large pale, bright yellow pompom blooms in big very double flowers. To grow at the back of a border or leaning against a wall.

• Flowering time August to October
• Height at maturity 2,20 m

See the product sheet

Alcea filicifolia Antwerp Stars Mix Seeds - Hollyhock

A short-lived but very hardy perennial plant with single, multicoloured flowers (yellow, copper-red, bright red, pink, pale pink and white). Perfect at the back of a border or leaning against a wall.

• Flowering time July to September
• Height at maturity 1,50 m

See the product sheet

Planting

Where to plant hollyhock?

Hardy down to -15°C, the hollyhock thrives almost everywhere in France, except perhaps in very windy areas. It is grown as a short-lived perennial (usually lives 3 or 4 years) in southern France where it tolerates drought well, and as an annual or a biennial in cooler climates.

Frequent spontaneous sowings allow renewal of young plants.

Although hollyhock adapts to many types of soil, it prefers rich, well-drained, calcareous soil.

It prefers to be placed on a sunny, sheltered, open site, which will encourage it to reach its full height. Once established, it does not like transplanting, so avoid disturbing it.

A too windy situation is a threat for this tall perennial. It requires staking to prevent stems breaking at the slightest gust or heavy rain, otherwise your border could look like a battlefield! Plant it along a wall or surround it with roses that will act as supporters.

With its tall silhouette, hollyhock is always highly structural in English or naturalistic gardens, where it asserts itself in country-style compositions to add movement and verticality.

Hollyhock fits into all natural settings, and can serve as a dazzling background plant for mixed borders, as flowers for beds, as avenue edging or to screen an unsightly wall.

When to plant hollyhock?

The hollyhock is preferably planted in spring from March to May after last frosts, or possibly from September to October.

How to plant hollyhock?

In open ground

Allow 4 to 6 plants per m², spacing them 50 cm apart and planting them irregularly for a more natural result.

• Soak root ball in a bucket of water before planting
• Work the soil well
• Make a gravel bed at bottom of hole for good drainage
• Plant, mixing planting compost into garden soil
• Stake hollyhocks most exposed to wind
• Firm soil and water regularly until established

When and how to sow hollyhock (Alcea rosea) seed When to sow - Under cover: sow February–April for flowering next summer. Early sowing under glass gives strong plants that can be planted out after all risk of hard frost. - Outdoors: sow April–May for plants that will establish during the season, or September–October for autumn sowing. Autumn-sown seed often benefit from natural cold stratification and produce earlier, stronger rosettes the following spring. - Note on life cycle: many hollyhocks behave as biennials (rosette first year, flower second year). Some modern varieties are perennial and may flower in first season if sown early. How to sow (step-by-step) 1. Prepare compost: use free-draining seed compost or a mix of multi-purpose compost and grit/vermiculite for good drainage. 2. Fill trays or pots: firm compost lightly; avoid compressing too hard. 3. Sow seed: hollyhock seed needs light to germinate. Scatter seed thinly on surface and press gently into compost. Do not bury deeply — a very fine dusting of compost or vermiculite (1–2 mm) is enough. 4. Water: mist or water from base to avoid displacing seed. Keep compost evenly moist but not waterlogged. 5. Cover and place: cover trays with clear lid or plastic to retain humidity, place in bright, warm spot (ideally 15–20°C). Light is important for germination. 6. Germination: expect seedlings in 7–21 days depending on temperature. Remove cover as seedlings appear to reduce damping-off risk. 7. Prick out: when seedlings have 2–3 true leaves, prick out into individual pots or modules. Use a good potting compost and keep in cool, bright place to harden off. 8. Plant out: plant outside after all risk of hard frost (usually from late spring). Space 30–45 cm apart, deeper planting is not necessary. If plants are leggy, plant slightly deeper to help stability. Growing tips - Position: full sun to light shade; shelter from strong winds is helpful for tall varieties. - Soil: fertile, well-drained soil. Incorporate garden compost before planting. - Support: tall spikes often need staking or support against a wall. - Feeding: feed with balanced liquid fertiliser during growing season for stronger flowering. - Watering: keep evenly moist, avoid overhead watering to reduce rust risk. - Pest and disease: hollyhock rust (Puccinia) can be a problem. Improve air circulation, remove infected leaves, and avoid wet foliage. Watch for slugs on young plants. After flowering - Deadhead to encourage prolonged flowering. If you want plants to self-seed, allow some seed to ripen and fall. - Cut back plants after flowering; many biennial types will die back after seed set. Quick timeline summary - Sowing under cover Feb–Apr → transplant and flower next summer. - Direct sow Apr–May → establish that season, likely flower following year if biennial. - Sow Sep–Oct outdoors → natural stratification, strong spring growth and earlier flowering. If you want specific advice for a named variety or local conditions (soil type, sheltered site), tell me variety name or location and I’ll tailor recommendations.

How to collect hollyhock seeds?

After flowering, collect the small brown seeds gathered in concentric circles inside the dried capsules: only harvest fully dry fruit. The hollyhock seeds have high seed viability for at least 4 years after harvest. Store dry and protected from light.

Hollyhock seed capsule (photo Jean-Pierre Bazard)

Direct sowing outdoors

Sowing is done in situ from March to May, depending on region, to obtain flowers the following year. Discover our advice to easily succeed with your hollyhock sowings.

• Crumb soil to depth of a spade
• Sow thinly by broadcasting in a sheltered spot in garden without sowing seeds too close together, or sow 2 to 3 seeds per pocket
• Cover with a few millimetres of seed compost
• Firm lightly with back of a rake
• Water with a fine spray and keep soil consistently moist
• Thin out to leave only one young plant every 30 cm in all directions

In seed trays

Hollyhock seeds are sown in summer from May to July for flowering the following year. You can also make earlier sowings in early spring for flowering during the next summer.

• Sow thinly by broadcasting in a seed tray or in buckets filled with seed compost mixed with a little sand
• Cover seeds with a little seed compost
• Firm lightly
• Keep moist under a frame sheltered from sun until germination, which occurs between 15 and 20 days
• Thin out some young plants at emergence
• Prick out young plants when they reach 7 cm high, that is when they have 3 or 4 leaves
• In autumn, plant them out in beds, spacing plants 30 cm in all directions or in troughs

Maintenance, pruning and care

Very easy to grow, hollyhock is undemanding and requires little maintenance.

Ideal for unattended gardens as it copes without watering once established: water regularly, especially during dry spells, but do not overwater and avoid wetting foliage.

Stake hollyhock in windy sites.

In autumn, apply a mulch to protect the stump from cold in regions with harsh winters.

Young plants of perennial hollyhocks lose vigour as they age and die out quickly, within three to four years. Do not hesitate to renew plants regularly.

How to prune hollyhocks?

In October, with a pruning shear, remove spent flower stems by cutting clumps back to soil level, or leave them to seed for self-sowing.

Possible diseases and pests

Hollyhock has a well-known enemy: rust, a leaf disease caused by a fungus visible as orange pustules left on the foliage. Harmless to the plant, it is mainly unsightly. Avoid its appearance by not watering the foliage, as moisture favours its development. As a preventive measure, in spring apply sprays of Bordeaux mixture combined with horsetail manure. If disease occurs: remove and burn infected plants. New series of hybrids (Thompson & Morgan) offer greater resistance to rust.

When first leaves appear, it is wise to protect them from feeding by slugs and snails. Apply slug treatment at planting and renew as necessary. Discover our 7 ways to fight slugs effectively and naturally and how to make a slug trap.

In dry weather, flea beetle, a small beetle, may appear, chewing leaves. To prevent this, mulch the base of hollyhocks, as this small insect dislikes moisture. You can also kill two birds with one stone by spreading wood ash around plants: its repellent effect will also deter slugs!

If hollyhocks are infested with aphids that make the leaves sticky and tacky: spray with water mixed with black soap.

Multiplication

Hollyhock self-seeds spontaneously and often in unexpected places if not cut back immediately after flowering. Raising hollyhock by sowing remains simple, but resulting colour is unpredictable because sowing rarely produces plants true to parent plant.

Seeds are harvested at ripeness if you have not cut all flower stalks; otherwise discover our hollyhock seed packets. Annual species generally self-seed and do not tolerate transplanting well, which is why they are sown in place in spring.

Sow at 13°C in February under cover or directly in place in April for growing as annuals. It is also possible to sow hollyhock seeds in July; they will then flower the following year.

Companion plants for hollyhocks

With their tall, highly architectural silhouettes, the hollyhocks are reliable choices for herbaceous borders, informal gardens, country gardens, natural or gardener-free spaces. Their majestic clusters of pink, black or white flowers are classic features of country gardens and English cottage gardens.

They are indispensable in pink or white gardens where they create delightfully romantic scenes. They are wonderful at the back of borders, or for covering walls of an enclosed garden.

Their pastel or stronger-coloured flowers allow superb pairings with dark or light forms. They will act as punctuation in a border of summer-flowering bushes such as hibiscus, buddleias, hydrangeas.

In shimmering, abundant mid-summer displays, varieties with soft shades will pair well with achilleas, monardas, ornamental alliums, nepetas, agastaches, nigellas, cosmos, two charming annuals.

Example of a romantic pairing: Nepeta ‘Six Hills Giant’, Centranthus ruber ‘Kempenhof’ (photo CaptainMish), Monarda ‘Croftway Pink’ (variety close to ‘Beauty of Cobham’), Alcea Rosea (photo Jürgen Mangelsdorf – Flickr), Salvia nemorosa ‘Amethyst’

In more contrasting, colourful scenes, pair hollyhocks with valerian, oriental poppies, eryngium and delphiniums to create combinations as opulent as they are ephemeral.

Hollyhocks with intense, deep colours — garnet red, blackcurrant or black — will let you create superb ‘Red and Black’ inspired schemes.

They also combine very well with each other: mix single-flowered varieties with generous pompom double-flowered cultivars.

They are excellent companions for old roses for charming pairings.

→ Discover more pairing ideas with hollyhocks in our guide!