Wondering what vegetable seeds to sow in March?

I love growing my own vegetables.  Growing your own food is one great way to take real positive action against climate change.  And growing your own vegetables brings your food miles down to zero!

If you’re a novice gardener here are some pointers of what seeds to sow in March.

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The Seeds to Sow Outside in March

what to sow in March


Sow your seeds 1cm deep into the soil. Space the seeds 10 cm apart, with 30 cm between rows.

Early Peas

Make a flat-bottomed trench around 5cm deep and 15cm wide. Sow the seeds evenly in the trench about 7.5 cm apart, before covering them with a light layer of soil.  If you sow a second row, space it at a distance equal to the height of the final pea crop.

Kohl Rabi

Sow seeds, 1 cm deep in rows 30 cm apart.


Sow thinly at a depth of 1cm, leaving 30 cm between rows.


Sow parsnip seeds thinly at depth of 13 mm, at 15cm intervals.  If growing in rows, sow each row 30 cm apart.

Early Turnips

Broad Beans

Sow seeds at a depth of 5cm, with and 20cm between each seed. They are best sown in double rows, with the rows 20cm part.

Brussels Sprouts

Sow seeds thinly at a depth of 13mm, with 15cm between rows.


Sow at a depth of 1 cm, 15 cm apart.  Leave 30 cm between rows.


Sow seeds thinly at a depth of 1cm, with a spacing of around 2.5 cm between each seed.  If sowing in rows, aim for 15 cm between each row.

Spinach Beets

Sow your seeds 2.5cm apart, at a depth of 1cm.  Leave 30 cm between rows.

The Seeds to Sow Undercover in March

March sowing ideas

Sowing undercover means in a greenhouse.  However, if you don’t have a greenhouse, or don’t have space for a greenhouse a simple cloche (a plastic or glass dome) or mini polytunnel will suffice.  We use plastic food pots rather than buying cloches to recycle and save money.

Summer Cabbages

Sow at a depth of 2cm, 25 cm apart.  Leave 30 cm between rows.

Early Cauliflowers

Sow seeds thinly at a depth of 2cm. Depending on the size of the variety you’re growing, rows should be between 15 cm apart for small varieties to 60 cm apart for larger ones.

Early Carrots

Thinly sow the seeds, at a depth of 1cm, in rows 15–30 cm apart. Thin out seedlings if necessary – you should aim for your carrot plants to be 5 – 7.5cm apart.

The Seeds to Sow in Heat in March

what should I sow in March

To sow in heat you can buy electric seed propagators.   If you’re looking for a thriftier option, you can plant seeds in small pots and sit them on a sunny windowsill.  You can pop a clear plastic bag over them to help trap heat and mositure.

It does mean for a couple of months your windowsills might be overrun with plant pots, however your efforts will be rewarded later in the summer when you have a substantial bounty of fresh vegetables that you’ve grown with your own fair hands!


Sow in small pots, then either place in a propagator or cover each pot with a clear plastic bag and place on a sunny windowsill. The seedlings need to be kept at around 18°C. Once two true leaves have formed, transplant them into 9cm pots.


Sow celeriac seeds in March in a pot in a propagator, at 15-18°C.  Once the seedling are hardy enough to be handled, transfer single seedlings to individual small pots.  Maintain temperatures of 15-18°C, as excessive cold can lead to premature flowering (bolting).


Sow seeds in small pots.  Place the pots in a heated propagator at about 18–21°C, or on a warm windowsill.  If you don’t have a heated propagator, cover your pots with a clear plastic bag or clear lid to trap moisture and warmth.  Transplant your seedlings into 7.5–9 cm pots when two true leaves have formed.


Sow at 18-21°C in small pots.


Sow cucumber seeds on their side, at a depth of 1cm, in small pots. Keep them warm in a heated propagator, greenhouse, or on a sunny indoor windowsill.

Hopefully, this guide on seeds to sow in March will keep you right this spring.  However, it’s not just about the vegetables in March.  Sowing some flowers, such as marigolds and nasturtiums at this time of year is also beneficial by way of companion planting.  These are good at discouraging pests from eating your precious seedlings, as well as being good at attracting pollinators, such as bees.

What seeds are you sowing this March?

Come back soon and visit my post on what seeds to sow in April.  In the meantime, happy growing!   I also have lots of other useful gardening guides on Moral Fibres.  From some great sustainable garden ideas to why you should choose peat-free compost. and how to attract bees to your garden.

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