Zinnia Growing GuideUpdated 11 days ago

Zinnias are colorful, easy-to-grow annuals that thrive in warm weather. Here’s how to successfully sow and grow zinnias:

When to Sow

• Outdoors: Zinnias should be sown after the last frost when soil temperatures reach above 60°F.
• Indoors: You can start seeds 4-6 weeks before the last frost to get a head start. For detailed planting tips, refer to this guide on growing zinnias.

Outdoor Sowing

• Choose a sunny location with well-drained soil.
• Sow seeds 1/4 inch deep and space them 9-12 inches apart. Lightly cover the seeds and water gently. Germination typically occurs within 5-7 days.
• For tips on avoiding common problems like pests or powdery mildew, read about zinnia issues and solutions.

Indoor Sowing

• Use seed trays with a seed-starting mix.
• Sow seeds 1/4 inch deep, keep the soil moist, and ensure plenty of light (grow lights may be necessary).
• Before transplanting, gradually introduce seedlings to outdoor conditions by hardening them off. More on this process can be found in the complete zinnia guide.

Care & Maintenance

• Light: Zinnias need full sun for optimal growth.
• Watering: Water consistently, especially during dry periods. Make sure the soil drains well to avoid root rot.
• Fertilizing: If your soil lacks nutrients, apply a light, balanced fertilizer during the growing season.
• Deadheading: Regularly removing spent blooms will encourage continuous flowering. Learn more about caring for different varieties, including Profusion zinnias.

Pests & Diseases

• Zinnias are generally low-maintenance, but they can attract pests like aphids, spider mites, and whiteflies. These can be managed with insecticidal soap.
• To prevent diseases like powdery mildew, make sure plants have good air circulation and water at the base to keep foliage dry. For additional tips, check out common zinnia problems.

Harvesting

• Zinnias are perfect for cut flowers. Harvest by cutting stems above a pair of leaves, ideally in the morning. Be sure to remove any foliage below the waterline when placing in a vase. For more harvesting tips, see the guide on zinnia reseeding and harvesting.

Garden Use

• Zinnias are great for attracting pollinators and are excellent in borders, beds, and containers. They also make great companion plants for vegetables like tomatoes, helping to attract beneficial insects. Learn about different zinnia varieties to add variety to your garden.