Zinnia seeds
Seed starting mix or potting soil
Seed trays or small pots
Watering can or spray bottle
Labels (optional)
Steps:
Choose the Right Time:

Zinnias are warm-season flowers, so it’s best to start them indoors 4-6 weeks before the last frost date in your area, or you can sow them directly outdoors after the last frost.
Prepare the Soil:

Use a well-draining seed starting mix or potting soil. Fill seed trays or small pots with the soil, leaving about a half-inch space at the top.
Sow the Seeds:

Plant zinnia seeds about ¼ inch deep. You can sprinkle a few seeds per cell or pot and later thin them out.
Watering:

Water the soil gently using a watering can or spray bottle to avoid displacing the seeds. Keep the soil consistently moist but not waterlogged.
Provide Light:

Zinnia seeds need light to germinate. Place the seed trays or pots in a sunny location or under grow lights for about 14-16 hours a day. If you’re using grow lights, keep them a few inches above the seedlings.
Maintain Temperature:

Zinnia seeds germinate best at temperatures between 70-75°F (21-24°C). You can use a seedling heat mat if needed.
Thin Seedlings:

Once the seedlings have a couple of true leaves, thin them out to one plant per cell or pot to give them enough space to grow.
Transplanting:

After the danger of frost has passed and the seedlings have grown strong enough to handle, harden them off by gradually exposing them to outdoor conditions over a week.
Transplant them into your garden or larger pots, spacing them about 6-18 inches apart depending on the variety.
Care and Maintenance:

Zinnias prefer full sun and well-drained soil. Water them regularly, especially during dry spells, but avoid overhead watering to reduce the risk of fungal diseases.
Deadhead spent flowers to encourage more blooms throughout the season.