Helianthus annuus
Sunflower
Sunflowers are a top US search flower for gardens, photos, and seed harvest — bold annuals that track the sun and bloom midsummer.
View GalleryCare Overview
Light
Full sun
Essential — shade produces weak, floppy stems.
Water
Weekly deep
Keep evenly moist until established; drought-tolerant later.
Temperature
70–85°F
Warm-season annual; plant after frost risk passes.
Humidity
Low–moderate
Open sites with breeze prevent mildew on leaves.
Soil
Average
Tolerant soils; avoid waterlogged beds.
Pet Safe
Generally safe
Seeds and petals are usually fine; avoid treated seed mixes.
Detailed Care Instructions
Sowing
Direct sow after last frost 1 inch deep. Thin seedlings so giants have room for roots.
Support
Stake varieties over 5 ft early. Wind and heavy flower heads snap stems.
Water & feed
Deep watering beats frequent sprinkles. Light fertilizer midseason helps branching types.
Harvest
Cut for vases when petals just open. For seed, wait until the back of the head yellows.
