Soil
Any sunny site with good drainage.
Position
Full sun.
Frost tolerant
Sunflower seedlings often escape damage from light frost, but sunflowers are warm-natured plants with no tolerance of freezing temperatures.
Feeding
Mix a light application of a balanced organic fertilizer into the soil prior to planting.
Companions
Beans, Squash, Pumpkin, Corn and Cucumber. A rare “shelter” plant, sunflowers can be used to create shade for sun-stressed crops. Tall varieties can serve as trellises for pole beans.
Spacing
Single Plants: 11″ (30cm) each way (minimum)
Rows: 11″ (30cm) with 11″ (30cm) row gap (minimum)
Sow and Plant
Sow sunflowers from late spring to early summer. Where summers are long and warm, make a second sowing for autumn harvest. Poke seeds into the soil about 1 inch (3 cm) deep and 3 inches (8 cm) apart. Thin to 12 inches (30 cm) apart in all directions for dwarf varieties. Extremely tall sunflowers or those that grow into multi-branched bushes may require 3 feet (1 meter) between plants.
Notes
Explore different sunflower varieties, which vary in size, color, growth habit, and the culinary quality of the seeds.
Harvesting
Cut sunflower heads when some of the seeds inside the edges appear ripe and fall away when rubbed, or when birds start harvesting them for you. Store in a warm, dry place.
Troubleshooting
Sunflowers will twist around to face the south or west, seeking the most abundant source of sun, which may be away from your garden.
