Hi Al,

Here's some info for you from the USDA:

Sunflower seeds usually are left on the flower to dry. The flower may have to be wrapped with cheesecloth to prevent the birds from eating the seeds.

Seeds may be dried in the sun or in a dehydrator at 100 degrees F. Higher temperature affects the flavor.

When seeds are dried, they can be roasted in a shallow pan at 300 degrees F for 10 to 15 minutes.

Betsy