Eggplant Seeds,
Casper

Start seeds indoors 8-10 weeks before your last frost date. Transplant outdoors only when all danger of frost has passed, and temperatures stay consistently above 65 F. Soil should be warmed to about 75-85 F for optimal germination; use a heat mat if necessary. In cooler zones, row covers or black plastic mulch can be used to retain soil warmth and extend the growing season as well. If you are not sure how to find your local frost dates, check out our blog post 'Our Experts Answer Questions, Share Resources.'

Sow seeds 1/4 inch deep in seed-starting mix. Harden off seedlings 7–10 days before transplanting. Plant them in full sun, spacing about 18 inches apart. Use well-draining, fertile soil with a pH of 6.0–7.0, enriched with compost or aged manure. Mulching around plants helps retain moisture, regulate soil temperature, and suppress weeds.

Keep the soil consistently moist but not soggy, watering deeply 1–2 times per week. Fertilize with a balanced or high-potassium fertilizer when plants start flowering and setting fruit. Protect plants from pests like flea beetles and aphids using lightweight row covers, neem oil, or insecticidal soap. Harvest fruits when they are glossy and just slightly soft.

• Eggplants are not insect-pollinated, so it is not necessary to isolate the plants very much to ensure pure seed. For home gardeners, an isolation distance of at least 40 feet is sufficient for seed saving.
• Allow fruit to become overripe; the fruit will become slightly wrinkled and soft.
• Scoop seeds out, rinse, and spread out to dry thoroughly.
• Properly stored eggplant seeds will remain viable for up to 4 years.