Sunflower (Helianthus annuus)

When to Plant

Sow seeds directly outdoors once all danger of frost has passed.

Location/Soil

Plants do best in rich, well drained soil in full sun.

For the best germination, keep the soil evenly moist, from seeding until the young plants emerge.

Planting & Growing Information

Sow seeds 13 mm (1/2″) deep and 8 cm (3″) apart.

Seeds germinate in 7-14 days.

Other Information

Although sunflowers are heat and drought tolerant, they will be far better when grown with ample moisture. This is especially true during the flowering stage.

Harvesting & Storage

Allow the sunflower plant to mature in the garden. Once mature (the yellow petals will have dried and fallen off and the back of the flower will be brown and dry) cut the head off the stem leaving approximately 1 foot of the stem attached. If the flower head/seeds have not totally dried in the garden, hang upside down in a warm, dry and well ventilated area until the seeds loosen and are completely dried. Seeds can start to drop from the flower head as they dry; wrap some cheesecloth around heads while drying to catch any that fall out during the drying process. Rub the seeds out of the head by hand. If the seeds are being saved for birds, just store in sealed containers in a dry location. If you want to roast for a snack, follow the following directions:

  1. Cover unshelled seeds with salted water, using 1/4 to 1/2 cup of salt per two quarts of water. Soak seeds in the salt solution overnight. Drain off the water the next morning and pat the seeds dry to remove excess moisture. (You can also roast the seeds unsalted, by simply skipping the soaking process).
  2. Preheat oven to 300°F.   Spread the sunflower seeds evenly on a cookie sheet or shallow pan and bake for 30 to 40 minutes or until golden brown, stirring occasionally. The seeds will often develop a small crack down the center as they roast. Test after each stirring to see if the seeds are completely roasted by tasting.
  3. After roasting, remove seeds from the oven, stir in 1 teaspoon of melted butter for every cup of seeds and allow them to cool completely. Add seasonings if desirable and then store the seeds in an airtight container.