Sunflower seeds consist of an outer hull, plus the meat--also called the kernel--inside. The hulls can be eaten, along with the kernel, but most people discard the hull, finding the fiber difficult to swallow. The type of sunflower seed used for human food is the black and white striped variety, while birds prefer black-oil seeds--the variety with an all black shell--because the shell is easier to penetrate and the kernel is high in oils. Either type can be fed to wildlife.
Allow the seeds to dry in place, on the plant. To discourage animals and birds from stealing your seeds, cover the flower heads with cheesecloth, hosiery or netting.
Wait until the flower head has lost its petals and begun to brown and die. Use a sharp knife or pruning shears to cut off the flower head. Leave 6 to 12 inches of stem attached.
Spread a piece of newspaper on a flat surface. Making a circular motion, rub your hand across the shells to dislodge them onto the paper. If you have several, rub two heads against one another, sparing your hands and halving the work. An alternate method is to hold the flower head over a paper bag as you rub the shells free. If the seeds are difficult to detach, the heads can be stored in a paper bag and allowed to dry for a longer period of time.
Spread the seeds on a screen, cardboard or newspaper to dry in full sun if the seeds require additional drying.
Use a dehydrator to finish drying the seeds if the weather prevents the seeds from drying outdoors. The National Center for Home Food Preservation recommends keeping the heat below 100 degrees, as higher temperatures can adversely affect the flavor of the seeds.
Roast shelled seeds by spreading them on a baking sheet and placing them in the oven at 300 degrees for 30 minutes. Adding salt or butter during the process is optional. Allow the seeds to cool and then store them in an airtight container.
Store seed for future crops by placing a portion of the seeds in a plastic bag in the freezer. Oregon State University recommends storing seeds in the same container with a cloth packet of dried milk to act as a desiccant.
Store dried seeds in a covered container or feed sack if you intend to use them for attracting and feeding wildlife. No further processing is required.