Growing guide

How to Grow Sunflowers

Big, cheerful, and foolproof from seed — a favorite with kids and pollinators.

The basics

What sunflowers need

• Sun — Full sun (6+ hours)
• Water — Moderate; deep but infrequent once established
• Harvest in 70–100 days
• Difficulty — Very easy

When to plant

Time it from your frost date

• Start indoors: Optional, 2–3 weeks early
• Transplant: After last frost (handle roots gently)
• Direct sow: 1 week after last frost where they’ll grow
• Best in Zones 2–11

How to plant

Three steps to a strong start

• 1. Direct-sow 1 in deep where plants will grow — they resent transplanting.
• 2. Thin to the spacing for your variety; giants need more room.
• 3. Stake tall types in windy sites.

Common problem

Toppling in wind

Tall varieties need staking or a sheltered spot.

Common problem

Birds/squirrels eating seedlings

Protect emerging seedlings with netting or cover.

Harvest

Picking sunflowers right

For cut flowers, snip when the bloom just opens, in the cool morning. For seeds, let heads dry on the stalk until the backs turn brown, then cover to beat the birds.

Gardeners ask

How tall do sunflowers grow?

It depends entirely on the variety — from compact 2-foot types to towering giants over 10 feet. Check the seed packet.

Keep growing

Get the full Sunflowers guide

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