Description

Growing Tips for Sunflowers

Sunflowers are best grown from seeds directly sown in the garden after the threat of frost has passed.

1. Choose a sunny location with average soil that drains well. Since sunflowers face the sun, ensure they are in an open area of your garden. Taller varieties should be planted at the north end to prevent shading other plants.
2. Prepare the soil by removing weeds and incorporating organic matter into the top 6-8 inches. Compost is an excellent choice for improving soil fertility and pH balance. If compost isn’t available, apply 1-2 inches of organic mulch after planting, which will decompose and enrich the soil over time. Conduct a soil test after the growing season to determine any necessary amendments for the next year.
3. Plant seeds ½ inch deep in groups of 2 or 3 seeds, spacing groups 18-24 inches apart depending on the variety.
4. Lightly firm the soil, water thoroughly, and maintain even moisture. Seedlings typically emerge within 7-10 days. Thin to one plant per group once seedlings have two sets of leaves.
5. Control weeds throughout the growing season as they compete with sunflowers for water, space, and nutrients. Cultivate regularly or use mulch to suppress weed growth. Organic mulches like shredded leaves not only retain soil moisture but also improve soil structure over time. Ensure mulch is kept away from plant stems to prevent potential rot.
6. Keep soil consistently moist but avoid overwatering. Established sunflowers can tolerate drought conditions.
7. Fertilization is unnecessary unless the soil is poor. Avoid over-fertilizing, as sunflowers are generally low maintenance.
8. Monitor for pests and diseases; consult your local Cooperative Extension Service for recommended controls in your area.
9. Some sunflower varieties produce only one bloom; remove plants after flowering to avoid disease issues in subsequent years.
10. Edible sunflowers mature in about 3 months. Harvest seeds when flower heads are dry but before fall or winter rains. Look for florets in the center of the flower disk to shrivel, and the back of the head to turn yellow or droop. Cut flower heads with a foot of stalk attached and dry them in a warm, dry, well-ventilated area. Use cheesecloth, netting, or a perforated paper bag to protect and collect seeds during drying.
11. Shorter sunflower varieties are suitable for containers using commercial potting mix.
12. Pollenless sunflower varieties make excellent cut flowers due to their prolonged bloom time and reduced pollen shedding.