When to Harvest Sunflower Heads to Save the Seeds?

Back of Flower Head

• Approximately 90 to 100 days after sunflowers germinate, they begin to reach the harvest stage. Check the back of the flower head regularly. When they are mature, the flower heads of sunflowers will begin to turn yellow, eventually turning brown and dry-looking. Harvest individual flower heads as they reach maturity.

Petals

• The large, usually yellow petals of sunflowers, are actually individual, non-seed-producing ray flowers. When the seeds are ripe and ready to harvest, nearly all of these yellow ray petals will have already dried up and fallen off.

Seeds

• The seed-producing flowers are contained in the large, dark-colored center disk. About 30 days after pollination, they ripen and are ready to harvest. When ripe, sunflower seeds are plump and the seed coats have turned to black with prominent white stripes.

Protect Seeds

• Squirrels and birds favor sunflower seeds. To keep these garden animals from eating your seeds, fasten paper lunch bags over the ripening seed heads when you notice the seeds plumping up. Secure the open end of the bag to the stem at the base of the flower with string. Check the contents every few days until the seeds begin to loosen from the seed head and appear dry. Rub them out by hand.