Don’t you just love early spring? I do! March is a great time to start sowing vegetable seeds for a successful growing season. So let’s see what we can get in pots and the ground this month!
Vegetables to Sow Indoors in March
March is a great time to start sowing seeds indoors. Get your vegetable garden off to an early start by focusing on crops that need warmth and longer growing seasons.
Tomatoes
Start tomato seeds indoors at the right time for early varieties. Use seed trays with multi-purpose compost and keep them on a sunny windowsill or in a heated greenhouse. They need warmth for quick germination, about 18-21°C. I use a heat mat for mine indoors.
Pick varieties suited for your space—outdoor sowings work well later, but indoor starts give plants a head start. Thin seedlings into small pots as they grow stronger by late spring to prepare them for planting out after the last frost date.
Chillies
Chillies thrive with early planting as they take so long to grow, especially during March. Sow seeds in small pots filled with light soil on a warm windowsill or use a heated propagator.
These fiery plants love warmth and need consistent temperatures for early growth. Chilli plants have a long growing season, so this time of year is perfect to give them an extra early crop boost. Keep the soil surface moist but not waterlogged to avoid issues like rot.
Late frosts can harm young plants, so wait until late May or June before moving them outdoors.
Sweet Peppers
Chillies and sweet peppers share similar growing needs. Sweet peppers are tender plants, so sow them indoors in early March for the best start. Use a heated propagator or warm windowsill to help germination since they love warmer weather.
Plant seeds about 1cm deep in moist soil. These crops grow slowly but reward patience. Once small plants form, transfer them into larger pots with fertile soil. By late May or early June, move them outside after all risk of frost has passed.
Keep soil well-drained and feed regularly for healthy summer crops.
Celeriac
Celeriac grows well when started indoors in March. Sow the seeds into trays filled with rich, organic matter. Keep the soil moist but not too wet. A heated propagator helps maintain good light levels and warmth for germination.
Thin seedlings as they grow to avoid overcrowding. Later, transplant young plants outdoors in late May or early summer after frost risk passes. Celeriac loves fertile, well-drained soil for strong roots by late August or early autumn harvests!
Vegetables to Sow Outdoors in March
March offers the perfect time to start sowing hardy vegetable seeds outside—get ready for a productive growing season!
Broad Beans
Broad beans are hardy and perfect for colder temperatures. Sow them directly outdoors in a shallow trench or individual drills. They grow best in sandy soil but can handle heavier ground if it’s well-drained.
Sow seeds early in March if the soil temperature allows it. Cover the planting area with a cold frame or clear plastic bag to protect against late frosts. By late summer, you’ll have a great addition to salads, stews, or stir-fries!
Carrots
Sow carrot seeds directly into shallow drills outdoors. Choose a sunny spot with light, well-drained soil. Early varieties can handle lower temperatures, making March the best time to start planting.
Cover seeds lightly and keep the soil moist during germination.
Avoid sowing in wet weather as this can compact the soil. Thin seedlings once they sprout to give them room to grow straight roots. Carrots grow well alongside onions or shallot sets, which help deter pests like carrot flies.
Beetroot
Carrots love well-drained soil, and so does beetroot. This vibrant root veg thrives in early spring if you sow directly into the ground by mid to late March. Choose outdoor varieties for best results during cold snaps.
Beetroot seeds prefer fertile, loose soil with plenty of sunshine. Leave 10cm gaps between each plant for room to grow. Early varieties like Boltardy are perfect at the start of the growing season.
Harvest tender baby beets or let them mature for a sweeter taste!
Kale
Kale is tough and loves the cold, which makes it perfect for March sowing. Direct sow kale seeds outdoors in well-drained soil by mid-March. Space them out to allow room for growth, ensuring each plant gets plenty of sunlight.
Hardy varieties like ‘Nero di Toscana’ grow best during chilly months.
This leafy green is packed with nutrients and thrives even in cold springs. Protect young kale plants from pests like cabbage white butterflies using fine netting. Sow now to enjoy fresh leaves throughout summer and beyond—a great addition before planting peas next!
Peas
Peas love cooler weather, making March a good time to sow them outdoors. Choose hardy varieties like “Early Onward” for reliable growth in early spring. Plant the seeds directly into well-drained soil that’s free of weeds and stones.
Place seeds about 5 cm apart in rows, leaving at least 30 cm between rows. Protect seedlings from birds with netting or cloches until they are stronger. By the end of March, your peas should show signs of sprouting, ready to grow into sturdy plants for an abundant summer harvest!
Tips for Successful Vegetable Sowing in March
Use a heated propagator for tender crops
Heated propagators speed up the germination of vegetable crops like early varieties of tomatoes and chillies that need more warmth. They provide a warm, controlled environment, perfect for starting new plants in March.
Place your celery seed or tomato plants inside and watch them thrive even during late winter chills. These devices protect young seedlings from frost, giving you healthy vegetable plants ready for spring planting.
Ensure soil is well-drained and fertile
Good soil is the key to healthy crops. Make sure it drains well to stop water from pooling and rotting seeds. Adding compost or manure can boost fertility, giving vegetables like carrots or leafy greens a great start.
Test soil by digging a small hole; if water sits, improve drainage with grit or sand. Fertile ground helps plants like peas and sweet pea plants thrive throughout spring. Don’t skip this step for plenty of vegetables later!
Protect young seedlings from late frosts
Cover seedlings with cloches, fleece, or old sheets during cold nights to trap warmth. This helps shield salad leaves, pak choi, and lettuce seeds from frost damage.
Plant hardy annuals like sweet peas in sheltered spots or use a cold frame. Early potatoes and onion sets can benefit from a thick layer of mulch for extra insulation against unexpected chills.
Conclusion
March is the perfect time to kick off your planting season. Sow indoors or outdoors, and enjoy watching your crops grow as spring unfolds. With a bit of care, you’ll have fresh veggies ready in no time! Get started now—your garden will thank you later!
Related posts: