Vegetable Seeds You Can Start Indoors in March (Zone 6B)
Spring is right around the corner and gardening planning is in full swing! The days are getting longer, the sun feels just a little warmer, and spring is finally in sight even if you still have snow on the ground like me. While it’s still too cold to plant outside in Zone 6B or your beds are all covered in snow, March is the perfect time to start some vegetable seeds indoors. There are a few of these that overlap with my seeds to start in February article. This is your reminder to start them now if you haven’t already! As always, I am looking specifically in Zone 6B although these seeds to start work in many other zones.
Starting seeds inside gives you a head start on the growing season, meaning stronger plants and (hopefully) an earlier and bigger harvest especially if you plan to do some succession planting with things like cabbage. So, let’s go over what veggies you can start indoors this month and whether they’re beginner-friendly or better suited for gardeners who enjoy a little challenge!
Tomatoes
- Beginner-Friendly? Yes! Tomatoes are one of the easiest and most rewarding vegetables to start from seed.
- Why Start Indoors? Tomatoes need a long growing season, and starting them indoors in March ensures they’ll be strong and ready for transplanting once the weather warms up.
- Tips: Use a seedling heat mat to help with germination and make sure they get plenty of light—either from a sunny window or grow lights.
Peppers (Sweet & Hot Peppers)
- Beginner-Friendly? Somewhat. They take a little patience but aren’t too difficult.
- Why Start Indoors? Peppers grow slowly and need warm temperatures to thrive. Starting them indoors in March gives them enough time to develop before they go outside.
- Tips: Peppers love heat, so a heat mat can help speed up germination. They also don’t like being overwatered, so let the soil dry slightly between watering.
Eggplant
- Beginner-Friendly? Somewhat. Similar to peppers, they can be slow growers.
- Why Start Indoors? Eggplants need a long growing season and plenty of warmth.
- Tips: Keep them in a warm, bright place and be patient! They take a little longer to sprout but are worth the wait.
Cabbage
- Beginner-Friendly? Yes!
- Why Start Indoors? Cabbage can be planted outside in early spring, but starting it indoors gives you a head start.
- Tips: Once your seedlings are strong enough, harden them off by exposing them to outdoor conditions gradually before transplanting.
Broccoli
- Beginner-Friendly? Yes!
- Why Start Indoors? Broccoli grows best in cooler weather, so starting it indoors ensures you get a good crop before summer heat sets in.
- Tips: Give broccoli seedlings plenty of light to prevent them from getting leggy.
Cauliflower
- Beginner-Friendly? A bit tricky. It’s more finicky than broccoli and cabbage.
- Why Start Indoors? Cauliflower is sensitive to temperature fluctuations, so giving it a strong start indoors helps ensure success.
- Tips: Be mindful of transplant shock. Cauliflower doesn’t like being moved too much, so handle seedlings carefully.
Lettuce
- Beginner-Friendly? Absolutely!
- Why Start Indoors? While lettuce can be sown directly outside, starting it indoors allows for an early harvest.
- Tips: Use shallow containers and keep the soil moist but not soggy. Lettuce doesn’t need as much warmth as other vegetables, so a sunny windowsill works fine.
Kale
- Beginner-Friendly? Yes! Kale is very forgiving.
- Why Start Indoors? Like lettuce, it can be direct sown outside, but an early indoor start leads to stronger plants.
- Tips: Kale grows quickly, so don’t start it too early unless you have space to keep it inside until transplanting time.
Swiss Chard
- Beginner-Friendly? Yes!
- Why Start Indoors? Swiss chard takes a little longer to establish, so starting it indoors gives it a head start.
- Tips: Transplant carefully since chard doesn’t like its roots being disturbed.
Leeks
- Beginner-Friendly? Yes!
- Why Start Indoors? Leeks take a long time to grow, so an early start is helpful.
- Tips: Keep the soil moist and trim the tops if they get too tall to encourage thicker stems.
Celery
- Beginner-Friendly? Not really. It’s one of the trickier vegetables to grow from seed. There are some easier varieties to grow if beginners still want to give it a try!
- Why Start Indoors? Celery grows very slowly and needs a head start. Plus this gives additional time for succession planting.
- Tips: Keep the soil evenly moist and don’t let it dry out. Celery is a bit fussy, but homegrown celery has amazing flavor!
Herbs (Basil, Parsley, Thyme, and Oregano)
- Beginner-Friendly? Yes!
- Why Start Indoors? Herbs grow well indoors and can be transplanted outside when the weather warms up. Many people grow herbs inside year round.
- Tips: Basil loves warmth, while parsley and thyme are more forgiving. Make sure they get plenty of light!
My Final Takeaways
Starting seeds indoors in March is one of the best ways to scratch that gardening itch while winter still lingers and it gives you more to add to the seeds you already started in February. Plus, you get a jump start on the growing season, which means healthier plants and an earlier harvest. If you’re a beginner, stick to easy-grow varieties like tomatoes, lettuce, kale, and herbs. If you’re up for a challenge, try your hand at celery or cauliflower!
No matter what you grow, just remember to have fun with it. Seed-starting is all about learning and experimenting, so don’t stress if things don’t go perfectly the first time. Before you know it, you’ll have strong little seedlings ready to take on the great outdoors—and a garden full of delicious homegrown veggies. Don’t be afraid to direct sow as well so you can see which ones perform better!