How to Grow Sunflower Seeds

How to Grow Sunflower Seeds

Updated on Dec 06, 2021
By Shannon McCabe

Latin name Helianthus annuus is an annual member of the aster family. Choose tall, multi-branching varieties as a stunning landscape flower or short dwarf single-head varieties for cut flower production.

HISTORY

Native to North America, sunflower has been a popular cultivated plant of the indigenous tribes of North America since at least 3000 B.C. Some archaeologists contend that the sunflower was cultivated before maize.

USES

  • Ornamental and edible.
  • Beds, back of borders, containers, row planting, cut flower production, pollinator garden, native wildflower garden, meadow, planted in the vegetable patch.
  • Sunflower shoots are edible, as are the seeds and even the whole immature heads. Visited by a range of bees like honeybees and native bees.
  • Visited by many beneficial insects and pollinators like hoverflies.

  • Seeds germinate in 7-14 days.
  • Direct seed after all chance of frost has passed and soil has reliably warmed. You can start indoors 3-4 weeks before transplanting, but be careful not to let plants become pot bound.
  • Planting depth will vary depending on seed size, as sunflower seed sizes range widely. A general rule of thumb is to plant seeds twice their own width, so a seed that is 1/2 inch wide should be planted 1 inch deep. Most sunflowers are planted at 1 inch deep.
  • Ideal germination temperature is 70-75 F.

  • Prefers full sun.
  • Provide light, well-drained soil.
  • Excessively nitrogen-rich soil will adversely affect blooming.
  • Space multi-branching types 18-24 inches apart and single-headed/ dwarf varieties just 4-6 inches apart.

PESTS/SPECIAL CONSIDERATIONS

  • While sunflowers are fairly disease-free and hardy, they are susceptible to white mold. To prevent this, keep foliage dry and provide well-drained soil.
  • If borers infest your sunflowers, spray leaves thoroughly with organic approved insecticidal oils when the adult insects are present and laying eggs on the leaves.

Saving sunflower seeds is very easy!

  • When petals die back and heads begin to dry and turn brown, place a paper bag over the heads to protect seeds from birds.
  • After a few days, the heads will dry to a dark brown. Bring the heads indoors and hang upside down in a dry area in direct sunlight for up to a week, shaking seeds free each day.
  • Store in a cool, dark, dry place.