Hollyhock

Sun

Full sun; light shade is tolerated, but flowering is usually poorer and stems may lean.

Water

Water regularly while establishing. Once established, water deeply during prolonged dry spells, especially while flower spikes are developing; avoid soggy soil.

Soil

Fertile, well-drained soil, preferably neutral to slightly alkaline. Heavy soil is suitable only where drainage is good.

Height

5-8 ft (1.5-2.4 m)

Spread

1-2 ft (0.3-0.6 m)

Flowers

Early to late summer, sometimes into early autumn; white, yellow, pink, apricot, red, purple or very dark maroon, with single or double flowers.

Foliage

Large, rounded to heart-shaped, shallowly lobed green leaves with a rough, hairy surface; lower leaves often become untidy during flowering.

Growth

Fast; usually forms a leafy rosette in its first year and flowers in its second, though some strains flower in their fi…

Care needed

Medium

• Water at soil level rather than over the leaves to reduce leaf wetness.
• Apply compost in spring; avoid heavy nitrogen feeding, which encourages soft, leafy growth.
• Mulch around the roots, keeping mulch clear of the crown.
• Stake tall stems early in exposed gardens, or grow beside a sunny fence with good airflow.
• Thin seedlings to about 18-24 in (0.45-0.6 m) apart to reduce crowding and rust.

Pruning. After flowering, cut spent spikes back to the basal leaves unless you want seed; this may encourage smaller later spikes. Remove dead stems and diseased foliage in autumn, keeping healthy basal growth.

Spring

Plant young plants, add compost and thin crowded self-sown seedlings.

Late spring

Install stakes before stems become tall; check lower leaves for rust.

Summer

Water during dry spells and tie growing stems loosely to supports.

Summer

Sow fresh seed for plants that will usually flower the following year.

Late summer

Cut back finished spikes, or let selected seed pods turn brown before collecting seed.

Autumn

Remove dead stems and rust-infected leaves, including fallen debris.

Winter

Keep crowns free of wet debris and check that water is not pooling around plants.

• Plant at the back of cottage borders for tall, colourful spires above lower flowers.
• Line a sunny fence or wall to soften its outline, leaving space for airflow and access.
• Combine with roses, catmint and hardy geraniums for a layered summer border.
• Use loose groups beside vegetable plots or garden gates for an informal, traditional effect.

Garden styles it suits: Cottage garden, English country, Traditional, Romantic rose garden, Farmhouse and Pollinator garden.

Plant it with: Roses, Catmint, Hardy geraniums, Lavender, Yarrow and Lady's mantle.

Wildlife: Single flowers provide pollen and nectar for bees, including bumblebees. Dense double flowers are generally less useful because insects have difficulty reaching their centres.

• Hollyhock rust causes orange-brown pustules beneath leaves and yellow patches above. Remove affected leaves promptly, clear debris and improve spacing; badly affected plants may need replacing.
• Slugs and snails eat young leaves and seedlings. Check after dark, remove hiding places and use wildlife-conscious controls where needed.
• Wind or heavy rain can snap tall flower stems. Stake early and choose a sheltered but airy position.
• Winter waterlogging can rot the crown. Improve drainage or move plants to a raised bed; do not bury the crown under wet mulch.

Not known to be toxic to cats, dogs, horses or people; no part is recognised as poisonous. The rough hairs on leaves and stems can irritate sensitive skin, so wear gloves if you react to them.

• Marsh mallow (Althaea officinalis)

  Has softly felted, grey-green leaves and much smaller, pale pink flowers in the leaf axils rather than the large, showy flowers of hollyhock.

• Common mallow (Malva sylvestris)

  Usually has a bushier, more branching habit and smaller purple-pink flowers marked with dark veins, rather than tall spikes of large flowers.

• Rose of Sharon (Hibiscus syriacus)

  Is a woody shrub with persistent branches and smaller, less rounded leaves; hollyhock has herbaceous flower stems that die back after flowering.

Alcea comes from an ancient Greek name for a mallow, and rosea is Latin for rosy.

Propagation. Grow from seed sown in spring or summer, preferably in individual pots or directly where plants will grow because the taproot dislikes disturbance. Transplant while young. Self-sown seedlings are common, but their flower colours and forms may differ from the parent.

Accepted botanical name

Alcea rosea

In the US and Canada

Introduced in Canada, the lower 48 states and Puerto Rico.

Native range

Turkey.

Measured

Average height 23 cm.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.