Rouge Royale (Helianthus/sterile)
Latin Name: H. annuus
Item #: 978C
Helianthus (No Pollen Type) Annual GREENHOUSE: Sow in 3 in/8 cm peat pots, 1/2 in/13 mm deep, using a light porous media. Cover seed lightly with soil and keep moist but never saturated. Germinate at 70°F/21°C soil temperature for 7 days around April 1st. Plants can be set out in garden in approximately 8 weeks. No pollen types are day neutral and can be grown in the greenhouse during short day - winter months or outdoors during the summer under longer day lengths in about 65 days.
DIRECT SOWING: Sow outdoors after danger of frost has past and soil temperatures are about 65 - 70°F/18 - 21°C. Plant seed in groups or hills at 3 seeds each, 1/4 in/6 mm deep, 12 - 16 in/31 - 41 cm apart. Thin to the strongest seedling. No pollen types thrive in hot sunny locations. Spray with a mild fungicide once or twice during humid periods to protect plants from disease. They make no pollen that produce seeds, which attract birds and increase the weight of the flower head at harvest time. Makes an excellent cut flower. To improve the performance in a vase, add a small amount of sugar to water.