Summer/fall bloom.Frost tender.
Sow seeds in well-worked soil in full sun when danger of frost is past and weather is warm and above 50°F (10°C) both day and night. Space seeds 2 to 3 inches apart in rows 12 inches apart, cover about 1/2 inch deep and gently firm soil. Keep soil evenly moist while awaiting germination.
Four weeks before last frost date, sow seeds 1/2 inch deep and 3 inches apart in a container of seed starting mix. Keep warm and moist and provide a strong light source until seedlings are ready to plant outside when temperatures rise above 50°F (10°C) day and night.
Space seedlings 8 to 12 inches apart when large enough to handle so plants have good air circulation and enough elbow room to grow and bloom freely.
Zinnias can grow in ordinary garden soil in full sun. For large, abundant flowers, thin before seedlings get crowded. Adequate spacing and regular, even watering discourages mildew and keeps zinnias productive. Pick just as blossoms begin opening and petals are tight. Cut long stems well back into the plant to keep plants branching low and producing best blooms for summer long bouquets.
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