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.
查看图库养护总览
光照
Full sun
Essential — shade produces weak, floppy stems.
浇水
Weekly deep
Keep evenly moist until established; drought-tolerant later.
温度
70–85°F
Warm-season annual; plant after frost risk passes.
湿度
Low–moderate
Open sites with breeze prevent mildew on leaves.
土壤
Average
Tolerant soils; avoid waterlogged beds.
宠物安全
Generally safe
Seeds and petals are usually fine; avoid treated seed mixes.
详细养护说明
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.
