It takes sunflowers roughly one more month to produce mature seeds after they start blooming.
If your sunflowers bloom in August, you could expect to harvest sunflower seeds in September.
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The Spruce / Colleen & Shannon Graham
Here are a few signs to watch for that will let you know exactly when to pick sunflower seeds.
Leave about 6 to 12 inches of stem attached to each bloom.
Allow the flowers to dry for a few weeks.
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The Spruce / Colleen & Shannon Graham
The Spruce / Colleen & Shannon Graham
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The Spruce / Colleen & Shannon Graham
The Spruce / Elise Bauer