Zinnia Seeds,
Aztec Burgundy Bicolor

Zinnia seeds should be planted soon after the last spring frost when the soil has warmed. In regions with shorter growing seasons, you can start seeds indoors 4 weeks before the last frost. For continuous blooms, sow seeds every couple of weeks throughout late spring and early summer​. If you’re not sure how to find your first and last frost dates, consult our blog post 'Our Experts Answer Questions, Share Resources.'

Sow seeds about ¼ inch deep in rich soil. Space the plants 9 to 12 inches apart for good air circulation, which helps prevent mildew. Zinnias prefer full sun, preferably 6 to 8 hours of direct sunlight daily. If starting indoors, use biodegradable pots or other means to minimize root disturbance when transplanting​.

Water regularly, but avoid wetting the foliage to prevent disease. A balanced fertilizer can be applied early in the season, but be careful not to use too much of it, as that can result in mildew. Pinching young plants encourages bushier growth, and deadheading extends the blooming period​.

• Allow the flowerhead containing the seeds to mature and dry on the plant.
• Clip off the flowerhead and place it in a paper bag or other container.
• Working over the top of another clean, opened container, rub the flowerheads between the palms to break them apart.
• The seeds can be separated from the chaff by first screening and then winnowing.
• Store in a cool, dry, dark place over winter.