What Seeds Should I Be Sowing in March?

9th March 2023

Spring is trying its best to reach us and in a few weeks, we are sure the weather will begin to turn making it the ideal time to start sowing those seeds ready for a good summer crop. But which seeds should you be focussing on first? Which seeds should we be sowing in March?

March is a great time to start sowing seeds for the upcoming growing season in the UK – albeit some will need sowing indoors before transferring outside later on in the year as seedlings.

Here are some seeds that can be sown in March:

Indoor Sowing

Some seeds need to be started off indoors to give them the best chance of growth at this time of year. Our UK weather can be pretty unpredictable so the use of a windowsill inside the home, a greenhouse or a garden room are some of the best ways to get your seedlings to pop up strong and healthy. The warmer the spot the better it is.

• Tomatoes
• Cucumber
• Celeriac
• Celery
• Chillies
• Sweet Peppers
• Kale
• Rocket*
• Spinach*

*Depending on your garden type and the weather you can choose to do these indoors or outdoors.

You will need:

• Sowing trays or individual growing tubes – these can be easily made out of toilet roll tubes
• Peat free compost
• Trowel
• Watering can
• Pen and labels
• Possibly a heat lamp if your chosen location isn’t warm/sunny enough

Once your seedlings begin to outgrow their tray you can thin and transfer them to either your greenhouse or straight out into beds or pots.

Sowing Outdoors with cover

Some seedlings are a little hardier and can be started off outside but with cover from a cloche or alternative just to protect them from those chilly nights and unexpected frost… and of course from the greedy birds!

Seeds that you can start off outside at this time of year include:

• Brussels Sprouts
• Summer Cabbage
• Beetroot
• Cauliflower
• Leeks
• Onions
• Peas
• Spring Onion
• Turnips
• Spinach
• Rocket

Sowing Outdoors

In March, the weather in the UK can still be quite cold, so it’s important to choose seeds that are hardy and can withstand lower temperatures. Here are some seeds that you can consider sowing outdoors in the UK in March:

• Peas – peas are hardy and can be sown directly into the ground in March.
• Broad beans – broad beans are another hardy crop that can be sown directly into the ground in March.
• Spinach – spinach is a hardy leafy vegetable that can be sown directly into the ground in March.
• Lettuce – lettuce is another leafy vegetable that can be sown directly into the ground in March.
• Carrots – carrots can be sown directly into the ground in March, but it’s important to choose a variety that is suited to cooler temperatures.
• Radishes – radishes are a quick-growing crop that can be sown directly into the ground in March.
• Onions – onion sets can be planted in March for an early crop.

Flower Seeds

This is the perfect time to get those hardy annuals out. to bring colour to your garden. Lots of lovely flowering plants can be planted right now, and these include:

• Sweet Peas 
• Wildflower Mixes
• California Poppies
• Cornflowers

Sowing these seeds in March will give you a really good start and you’ll soon discover that growing your own can be really satisfying and with the right seeds, growing location and care and attention you could be eating crops right straight from your garden in no time.