Description
HOW TO PLANT:
Good seed-to-soil contact is essential for successful seed germination.
Site Preparation: Sunflowers are not overly picky about solid but prefer well-draining, slightly acidic to neutral soil (pH 6.0-7.5). Best results are obtained direct sowing into warm soil (50F+) in full sun (6-8+ hours).
Timing: A spring planting before anticipated rainfall is best. Summer plantings can also be successful with adequate irrigation or rainfall to insure germination and establishment.
Planting: A seeding rate of 25 lbs. per acre is recommended. An inert carrier such as vermiculite may be helpful to evenly spread the seed. Seeding can be accomplished with a drill (plant to a depth of 1-2 inches and firm well) or with a drop spreader, cyclone spreader, or by hand. For larger, wider flower heads, give them more space. Closer spacing produces smaller heads and thinner stems. Make rows about 30 inches apart. Stagger plantings over 5-6 weeks to keep enjoying continuous blooms.
Establishment: Best results are obtained if the soil is kept moist for a month after planting. Some seedlings will normally appear in two weeks and other will take up to four weeks. An average soil temperature required to germinate wildflowers is 65 degrees F.
Management: Use a slow-release or low-nitrogen fertilizer. Too much nitrogen can cause excessive leaf growth and fewer, smaller flowers. Sunflowers are heavy feeders so the soil needs to be nutrient-rich with organic matter or composted (aged) manure. While drought-tolerant once established, keep soil moist for seedlings. Water deeply around the root zone, 3-4 inches away from the stem, to encourage deep root development. Taller varieties may need staking to prevent breaking in high winds.
Flowering: Most varieties mature in 70-95 days
