UK growing guide · Spring
What can I plant in March?
Last updated
March is the month most UK growers have been waiting for. Vegetables to plant in March in the UK cover both lists: tomatoes, peppers and brassicas under cover, and peas, onions, roots and salads outside once the soil is workable.
It is also the month that catches people out. A warm weekend is not the end of frost, and seed sown into cold wet clay often comes up with the seed you sow later, if it comes up at all.
What to sow in March
Vegetables to plant in March in the UK, split between sowing under cover and sowing outside.
Indoors or under cover
Sow the heat-lovers now if you have not already, and start the brassicas that will be planted out in early summer. Courgettes and cucumbers can wait until April unless you have room to pot them on.
Tomatoes — by the middle of the month- Chillies — if they are not already up
Sweet peppers — keep the pots warm
Aubergines — they dislike a check- Celery and celeriac — they need the whole season
Broccoli — calabrese and sprouting, for later transplanting
Cauliflower — sow in modules
Brussels sprouts — an early sowing for big plants
Lettuce — sow a small batch
Peas — in modules if the soil is still cold- Broad beans — in pots, same reason
Courgettes — late March only if you can keep them warm
Outdoors
Sow outside when the soil crumbles and is not sticking to your tools. Fleece or a cloche over the bed for a week or two beforehand helps on cold plots.
- Peas — with sticks or netting ready
- Broad beans — if you did not sow in autumn
Onion sets — firm, free-draining soil- Shallots
Carrots — a fine seedbed, thin later
Beetroot — clusters, so you will thin them- Parsnips — sow fresh seed, they hate delay
Spinach- Lettuce — and other hardy salads
Radishes — a short row, every few weeks
Early potatoes — when the ground is not sodden
What to plant out in March
Plant sets, potatoes and anything hardy you raised in pots. Leave tomatoes, courgettes, beans and sweetcorn inside. A late frost will finish them.
- Onion sets
- Early potatoes — cover shoots if frost is forecast
- Broad beans — hardened off plants from pots
- Lettuce — hardened off, under fleece if nights are cold
Garlic — last chance for a useful bulb
What to harvest in March
You are eating the last of winter and the first of spring. Don't strip purple sprouting: more spears follow if you cut the central one first.
- Purple sprouting broccoli
- Leeks — before they run to flower
Kale- Brussels sprouts — finish them before they blow
- Spring cabbage
- Spinach — overwintered plants
- Rhubarb — established crowns in milder gardens
March jobs on the plot
March fills the seed trays and the beds. Write down what went where, or June becomes a guessing game.
Prepare seedbeds, don't force them
Rake a fine surface once the soil is dry enough. If it smears, wait. Sandy soil is ready before clay.
Feed fruit trees and bushes
A handful of general fertiliser around apples, pears, currants and gooseberries, then mulch. Keep mulch off the trunk.
Put pea supports in at sowing
Twiggy sticks or netting are much easier now than when the row is a tangle.
Watch for slugs as it warms
Seedlings disappear overnight. Clear hiding places around new rows, and check after rain.
Finish winter pruning
Apples and pears should be done before the buds open. Stone fruit still waits until summer.
Frost and where you garden
North and south in March
Late frosts are normal in March across the UK. Emerging potato shoots and blossom on early fruit need fleece when a frost is forecast. A mild week does not mean frost has finished.
Further north, and high ground
In northern England, Scotland and on high ground, keep outdoor sowing for the hardiest crops and be ready to cover them. Heavy or wet soil may not be workable until late March or April. Tender plants stay indoors.
The south and sheltered coasts
Southern and western gardens can sow peas, broad beans, onion sets and early potatoes sooner, especially on light soil. Even there, have fleece ready. Coastal plots are milder, but a clear night still bites.
Easy mistakes in March
March rewards people who match the sowing to the soil in front of them, not to the date on the packet alone.
Sowing into soil that sticks to your boots
Seed rots, and you damage the ground. Wait, or start the crop in modules.
Putting tomatoes outside
They are indoor plants until your own last frost has passed, often May in the south and into June further north.
Sowing courgettes too soon
A March courgette becomes a hungry pot-bound plant long before it is safe outside. April is early enough for most of us.
One huge sowing of salad
Radishes, lettuce and spinach are happier sown every few weeks. Otherwise you get a glut, then a gap.
Keep March on the dashboard
Sproutly is a web garden diary for UK fruit and veg growers. Add the plants and the jobs, then see what's due on your dashboard.
Record your sowings
Note what you sowed in March, and which bed it went in.
Plan the month's jobs
Add planting, covering and picking as tasks with a due date.
See what's due
Your dashboard shows what's due and what's overdue. Sproutly does not email you or send a push to your phone.
Sketch the beds
Use the garden planner to try a layout before you plant it for real.
Ready to plan your March garden?
Add this month's plants and jobs to your diary. Basic is free for up to 3 plants and 3 tasks. Pro is £5 a month if you want more, including recurring tasks.
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Gardening advice is provided as a general guide based on typical UK conditions. Weather soil and local climate can vary so always use your judgement and adjust timing as needed for your own garden.