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Know what to sow, when to harvest, and discover recipes for your garden produce.
March marks the real start of the growing season. The days are getting longer, the soil is slowly warming, and the urge to get your hands dirty becomes impossible to ignore. Whether you’re a seasoned grower or picking up a trowel for the first time, March is packed with opportunity.
Here’s your complete guide to what to sow in March — for both UK gardeners and those growing in the USA.
Why March Is Such an Important Month
March sits in that exciting window where you can start sowing indoors in earnest, and in milder regions, begin direct sowing outside. Getting your timing right in March sets up your entire season — a few weeks’ head start on tomatoes, peppers and aubergines in March means a much heavier harvest come summer.
What to Sow Indoors in March (UK)
These crops need warmth to germinate, so start them on a sunny windowsill or in a propagator:
Tomatoes — Start in small pots, keep at 18–21°C. They’ll be ready to plant out after the last frost (usually May/June depending on your region).
Peppers & Chillies — These need the longest growing season so March is actually the ideal time. Keep warm and be patient — they’re slow germinators.
Aubergine — Same treatment as peppers. A propagator really helps here.
Courgettes — Sow on their sides in small pots. They germinate quickly and grow fast, so don’t start too early or they’ll outgrow their space before it’s warm enough outside.
Cucumbers — Indoor or greenhouse varieties can be started now.
Celery & Celeriac — Sow on the surface of compost as they need light to germinate. These are slow growers so March is the right time.
Leeks — Sow in a tray and prick out when large enough to handle.
What to Sow Direct Outside in March (UK)
As long as your soil is workable and not waterlogged, you can sow directly outdoors from March:
Broad Beans — Hardy and can handle late frosts. One of the best direct sows of the month.
Peas — Sow in a shallow trench or guttering. Protect from mice with wire netting.
Onion Sets & Shallots — Push into prepared soil, tip just showing.
Garlic — If you didn’t plant in autumn, March is your last chance. Still worth doing.
Lettuce — Under cloches in cooler areas, direct in mild spots.
Spinach & Chard — Both cold-tolerant and great for early salads.
Radishes — Fastest crop in the garden. Sow now for a harvest in 4–6 weeks.
Parsnips — Need a long season. Sow as soon as soil is workable.
Beetroot — Wait until late March in colder areas. A brilliant crop for beginners.
Carrots — Sow thinly in well-prepared, stone-free soil.
Kale & Cabbage — Sow in a seedbed and transplant later.
What to Sow in March (USA — by USDA Zone)
Zones 3–4 — Focus on indoor seed starting this month. Tomatoes, peppers, onions and leeks can all be started indoors 6–8 weeks before your last frost date.
Zones 5–6 — Start tomatoes, peppers, aubergine, celery and celeriac indoors. Direct sow peas, spinach, lettuce and onion sets outside if soil is workable.
Zones 7–8 — Start tomatoes indoors and transplant cool-season crops outside: lettuce, spinach, carrots, beetroot, peas and brassicas.
Zones 9–10 — Focus on warm-season crops now. Direct sow beans, cucumbers, courgettes and squash. Tomatoes and peppers can go out if frost risk has passed.
March Gardening Tips
Check your last frost date first. Everything hinges on this. The GrowMore CookMore app uses your location to calculate your personal frost dates and adjusts all sowing advice accordingly.
Prepare your beds. Dig in compost or well-rotted manure before sowing. Good soil preparation in March pays dividends all season.
Label everything. Seedlings all look the same when they first emerge. Label as you sow — you’ll thank yourself later.
Harden off before planting out. Any seedlings started indoors need to be gradually acclimatised to outdoor conditions over 7–10 days before planting out permanently.
What the GrowMore CookMore App Does in March
The app shows you exactly what’s ready to sow in your specific location this month — both indoors and out. It tracks your growing days so you know when each crop is likely to be ready for harvest, and then suggests recipes matched to what you’ll be bringing in from the garden later in the season.
It’s the gardening companion that bridges the gap between the seed packet and the dinner table.
Tony Smith is a gardener, YouTuber and the creator of the GrowMore CookMore app. He grows vegetables in the UK and shares the journey with 50,000 subscribers on YouTube.
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