How to grow Sunflower Seeds
Sunflowers are surprisingly easy and rewarding to grow from seed, producing bold, cheerful flowers that bring height, colour, and pollinator interest to the garden.
When to Sow Sunflower Seeds
Start seeds indoors 6–8 weeks before the last frost under grow lights or on a sunny windowsill. For direct sowing, wait until after the last frost in your area.
Sowing & Spacing
Sow seeds 2.5–5 cm deep outdoors, spacing dwarf varieties 15 cm apart and taller ones 30–45 cm apart.
Choosing a Location
Select a sunny spot with at least 6–8 hours of direct sunlight daily. Sunflowers prefer well-draining soil. Amend clay soil with compost or sand for better drainage.
Indoor Sowing
For indoor sowing, use individual pots with seed starting mix. Sow 2 seeds per pot and thin later to the strongest seedling.
Care & Maintenance
Once seedlings emerge, thin them to the desired spacing. Water regularly, especially during hot and dry periods. Aim to keep the soil evenly moist but not waterlogged.
Taller varieties may need staking to support their heavy heads. Use stakes or poles and loosely tie the stem to the support as it grows.
Blooming
Expect sunflowers to bloom 8–12 weeks after sowing, typically from mid-summer to early fall. Deadhead spent flowers to encourage further blooming.