Do I need to stake them?

Yes, their tall stalks are prone to snapping in strong winds.

Why are there orange spots on the leaves?

This is almost certainly hollyhock rust, a common fungal issue.

Plant guide

Hollyhock.

Alcea rosea

Pronounced al-SEE-uh RO-zee-uh

Also known as Black Hollyhock, Common hollyhock, Hollyhock

Hollyhocks are classic cottage garden staples that bring height and charm to any sunny border. These impressive plants produce tall, sturdy spikes covered in large, showy blooms throughout the summer. They are often grown as biennials, meaning they spend their first year establishing foliage and bloom in their second.

Another photo of Hollyhock — Photo by wandering_shr00m (CC BY) via iNaturalist

At a glance

Care level: Easy
Plant type: Biennial or short lived perennial
Light: Full sun
Indoor light: Direct sun
Water: Every 3 to 7 days
Mature size: 8 feet
Growth rate: Fast
Hardiness: USDA 3 to 9
Bloom time: Mid to late summer

Care

Plant these in a spot that gets plenty of sun and has well draining soil to keep them happy. Stake the tall flower spikes if you live in a windy area to prevent them from snapping. Keep an eye out for rust on the leaves, which is a common fungal issue that looks like orange spots.

Watering: Water consistently to keep the soil moist but not soggy, especially during dry spells.
Feeding: Apply a balanced liquid fertilizer once a month during the active growing season.
Pruning: Deadhead spent flowers to encourage more blooms and cut the stalks back to the ground after they finish flowering.
Repotting: These plants have deep taproots and generally prefer to stay in the ground rather than containers.
Soil: Rich, well draining soil
Soil pH: 6.0 to 8.0
Temperature: -35 to 35°C
Humidity: 40 to 70%

Safety

People: The plant is generally considered non toxic to humans.
Pets: Hollyhocks are generally considered non toxic to cats and dogs.
Children: The tall, heavy stalks can be a tipping hazard if children climb on them, and the hairy leaves might cause mild skin irritation.
Contact allergens: Contact with the leaves can cause skin irritation in sensitive individuals due to tiny hairs.
Airborne allergens: The pollen can be a significant allergen for those sensitive to airborne particles during the bloom season.
Edibility: While the flowers and leaves are technically edible, they are often treated with pesticides in nurseries and should be avoided unless grown organically.

How to identify it

Tall, unbranched flower spikes
Large, heart shaped, lobed leaves
Showy, saucer shaped flowers
Fuzzy, hairy stems and foliage

Height: 1.5 to 2.5m
Spread: 0.45 to 0.6m
Leaves: green, deciduous
Flowers: pink, red, white, yellow, purple, 8 to 12cm

Problems to watch for

By symptom

Plant problems by symptom

Check your hollyhock from a photo

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Growing it

Propagation: seed
When to plant: spring, early autumn

Plant them against a wall or fence to provide natural shelter from the wind.

Grows well with

Lavender · They share similar sun and soil requirements.
Delphinium · Both provide dramatic vertical interest in the back of a border.

Similar species

Common Mallow · It is a close relative with similar flower structures.

Science

Family: Malvaceae
Genus: Alcea
Order: Malvales
Class: Magnoliopsida
Native range: Central and southwestern Asia.
Conservation: Not of conservation concern.

They thrive in open, sunny areas where they can easily self seed to maintain their population.

Value to wildlife: nectar source
Pollinators: bees, butterflies, hummingbirds
Uses: cottage gardens, background planting, cut flowers

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 2/9
Soil reaction: 6/9
Light: 8/9
Temperature: 5/9
Moisture: 5/9
Nutrients: 6/9

Taxonomy resolved against GBIF.

Questions people ask

Do I need to stake them?: Yes, their tall stalks are prone to snapping in strong winds.
Why are there orange spots on the leaves?: This is almost certainly hollyhock rust, a common fungal issue.

Where the name comes from

The name Alcea comes from the Greek word for mallow, while rosea refers to the rose like appearance of the flowers.

Good to know

Hollyhocks are technically short lived perennials often treated as biennials.
They can reach heights of over 8 feet in ideal conditions.
The flowers open from the bottom of the stalk to the top over several weeks.

Keep your hollyhock growing

This page is a general guide. Save your plant in Pocket Botanist and you get care reminders timed for this plant, plus a care history that shows what worked.

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This guide was generated with AI on September 26, 2026 and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.