How to Grow Hollyhocks (UK guide)
Hollyhocks bring classic cottage-garden charm, rising tall with blooms from midsummer into early autumn. They’re simple to grow in UK conditions and loved by bees. Sow once and enjoy their colour year after year, as many self-seed reliably.
On Growing Hollyhocks
Hollyhocks are biennials that form strong leafy growth in their first year, then send up tall flowering spires the next summer. Give them sunshine, shelter from strong wind, and a little space for airflow. With the right conditions, they’ll naturalise beautifully.
On Sowing
Keep warm without light till germination.
How to Grow Hollyhocks from Seed
- 01Sow seeds 5cm apart and cover lightly with compost.
- 02Keep trays warm (around 18–20°C) for 10–14 days, then move seedlings into bright light.
- 03Pot on once roots appear at the base, then grow on until sturdy.
- 04For outdoor sowing, scatter seeds in late spring or summer for flowering the following year.
You will need
- 01Hollyhock Seed Packet
- 02Seed Compost
- 03Growing tray
- 04Clear bag or growing dome
Caring for Young Hollyhock Sprouts
Protect young hollyhock plants from slugs and sudden cold by keeping seedlings growing on in pots until they’re sturdy, then hardening them off outdoors for a week. Water at the base, not over the leaves, and avoid letting small plants sit in soggy compost so they develop deep, resilient roots.
Plant Calendar
What Hollyhocks Needs
Watering
Water regularly while young or freshly planted. Once established, hollyhocks prefer soil that’s moist but not waterlogged.
Feeding
Grow best in fertile ground. They won’t usually need extra feeding in borders, but plants in pots benefit from a fortnightly liquid feed.
Protection
Plant near walls or fences to shield the tall stems from wind. Use canes or a mesh support for extra stability.
Hollyhocks FAQs
Hollyhock rust is common. Improve airflow, avoid overhead watering, and remove lower affected leaves. Mulching helps reduce soil splash that spreads spores.
Yes, especially tall varieties. Stake early in the season with canes or a mesh support to stop wind damage
Biennial types usually bloom in year two. Some annual varieties flower in the first summer if sown early.
Full sun is best — around 6–8 hours daily. Too much shade leads to leggy growth and fewer blooms.
Water deeply once a week in dry spells. Keep the soil evenly moist while establishing, then allow the top layer to dry slightly between waterings.
COTTAGE: Abundant planting that feels natural and tousled — a mix of flowers, herbs and climbers tumbling together.
