Tomato seeds do not need a lot of light to germinate, but they do need some warmth and moisture. The ideal temperature for tomato seed germination is between 70-85°F, and the seeds should be kept in a well-draining soil or seed starting mix that is consistently moist but not waterlogged.
In terms of light, tomato seeds can germinate in low light conditions, but they will grow faster and more robustly with additional light. It is best to provide the seedlings with bright, indirect light for several hours each day, or to place them under fluorescent lights set about 2-4 inches above the seed trays. If the seedlings are grown in low light conditions, they may become tall and spindly and may be more susceptible to disease and pest problems.
Once the seedlings have emerged and are growing well, they will benefit from additional light and should be given at least 6-8 hours of bright, direct sunlight each day, or placed under fluorescent lights for 14-16 hours each day. This will help them grow strong and healthy and will encourage good fruit production once they are transplanted into a garden bed or larger container.
Read more
Cold Stratification for Seeds in 4 Easy Steps
Seed Stratification: What Seeds Require Cold Treatment
Seed Stratification: A Comprehensive Guide to This Seed Germination Trick
What Is Seed Stratification?
Seed Stratification Explained & Preventing Fungus Gnats: Increase Germination and Stop Problems
Germination Requirements for Annuals and Vegetables
Do Seeds Need Light To Germinate Or Not?
Lighting For Seedlings: A Beginner's Guide To Grow Lights For Seedlings
How to Germinate Seeds Successfully Every Time
Protecting Your Garden From Frost
How to Pre-Sprout Seeds for Faster Germination
How to Germinate Seeds Quickly in 6 Steps
Quick and Easy Sprouting Guide: How To Sprout Vegetable Seeds
How do I clean tomato seeds 