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I’ve grown my own fruit and veg for about fifteen years, the last three on an allotment in East Sussex. March is the best month to get ahead, and the worst month to rush.
The jobs below run in roughly the order they come up, from early March to the end of the month, with an early, mid and late March summary further down.
1. Walk the plot and take stock
Before you pick up a single tool, walk every bed slowly. Note what survived the winter, what’s bolted, and where the ground is waterlogged. Ten minutes of looking saves hours of wasted effort later. A small notebook helps — jot down which beds need clearing, where the soil looks compacted, and anything that surprised you. On chalk, also look for where the surface has panned over winter and needs loosening.
2. Clear winter debris
Pull up spent brassica stalks, old bean canes, and anything that’s been sitting since autumn. If it’s woody, chop it small and add it to the compost. Leaving this stuff another month just makes the job worse. While you’re at it, turn the compost heap with a fork, working from the outside in. A heap left since autumn has gone airless, and turning it restarts the breakdown, so it is usable by early summer rather than sitting as a dense, half-finished block. Add what March gives you: kitchen scraps saved over winter, torn cardboard (spring heaps are usually short of brown material) and the early weeds pulled from paths. On chalk, which loses organic matter quickly, that compost is the most valuable thing the plot makes. This is the unglamorous work of March, but arriving at a clear plot in April — when everything is pressing — is worth every muddy hour of it.
3. Start chitting early potatoes
If you haven’t already, stand your seed potatoes upright in egg boxes or old trays somewhere cool and light indoors. You’re looking for short, stubby green shoots rather than long pale ones. A spare bedroom windowsill works perfectly. In the south of England, first earlies can go in from mid-March. Further north, wait until the soil has warmed more. On an exposed coastal plot it pays to wait until the soil is reliably above 7°C, which may not be until late March or early April.
4. Prepare potato trenches
Dig trenches roughly 15cm deep and 60cm apart. If your soil is chalky (common across the south-east), adding organic matter makes an enormous difference to moisture retention — chalk drains fast and potatoes need consistent moisture to bulk up properly. Work a generous shovelful of garden compost into each trench before the seed potatoes go in; on chalk, the difference compared with unimproved ground is usually very noticeable.
5. Sow under cover
March is prime time for getting things going on the windowsill or in an unheated greenhouse. Good candidates: tomatoes, peppers, aubergines, lettuce, leeks, and early brassicas like calabrese. Use modular trays rather than scattering seeds into larger trays — each seedling develops its own root system without disturbance, and you waste far fewer seeds. Once you’ve sown in modules, it’s hard to go back to open seed trays for anything that will be transplanted.
Also worth starting under cover now: celery and celeriac (sow on the surface, as they need light to germinate), onions if you grow them from seed rather than sets, and sweet peas if you didn’t sow them in autumn. Peas can be started in pots or lengths of guttering under cover, ready to plant out in April. Courgettes and squash can wait until late March or April; they grow fast and gain nothing from an early start.
Seed starting essentials
- Modular seed trays with clear lids — the most useful propagation kit for any size plot
- Peat-free seed compost — not multipurpose; seed compost drains better and has the right nutrient level for germination
- Plant labels and a pencil — a pencil outlasts any pen in a damp shed
Budget around £15–20 for the basics. Thompson & Morgan carry seeds and propagation kit.
6. Direct sow hardy crops
If your soil isn’t waterlogged and the worst frosts have passed, you can sow directly into prepared beds. Broad beans, early peas, radishes, spring onions, and parsnips can all go in now. Cover rows with fleece or cloches if cold nights are forecast. My half plot is on chalk with thin topsoil, on an exposed coastal site, and that is a fair illustration of the two things to weigh: chalk drains quickly, so it is usually workable early in March, but on an exposed site a cold wind overnight can check early sowings, so they are worth covering from the start.
7. Plant onion sets and shallots
Push onion sets gently into the soil so the tips just show. Space about 10cm apart in rows 30cm apart. Shallots want a little more room. Birds can be a nuisance, pulling sets out for fun — keep some netting handy. Net onion sets the same day you plant them; waiting until you notice the problem is usually too late.
8. Mulch fruit bushes and trees
Spread a generous layer of well-rotted compost or bark around the base of fruit bushes, raspberry canes, and any fruit trees. Keep the mulch a few centimetres away from the stems to avoid rot. On chalk soil this is particularly valuable — it feeds the soil, suppresses weeds, and conserves the moisture that chalk drains away so quickly. One of those jobs that pays back all season without requiring any more attention.
9. Check and repair structures
Walk along your raised beds and check for loose boards. Inspect bean frames, fruit cages, and netting. Replace rotted string with fresh jute or biodegradable twine. If your shed needs a coat of wood preserver, March is the time — a quick treatment now means it’s protected before the growing season absorbs all your weekends.
10. Top up paths
Allotment paths take a battering over winter. A few bags of bark chippings spread along main walkways keeps mud at bay and makes the plot much more pleasant to work. Many sites get free wood chip from local tree surgeons — well worth asking around if yours doesn’t already have a supply.
11. Plan your crop rotation
If you haven’t done this over winter, sketch a rough plan now. The basic principle is simple: don’t grow the same family of crops in the same bed two years running. Rotate brassicas, legumes, roots, and potatoes around four beds on a cycle. Even a rough rotation reduces soil-borne disease and keeps fertility more balanced. A phone photo of last year’s beds is an easy reminder of where things were.
12. Enjoy being there
This might sound daft, but it matters. March on the allotment is quiet, uncrowded, and full of potential. Bring a flask. Sit on your bench for five minutes. Watch what’s happening. The plot doesn’t need you to rush. The light in early March — low and clear, longer than February — makes it one of the most pleasant times of year to be there.
Check the soil before you dig
March soil is often wetter than it looks, and digging or walking on wet ground compacts it and damages the structure for the whole season. Squeeze a handful: if it forms a ball that holds together when you open your hand, it is too wet; if it crumbles, it is ready. To get ahead on a particular bed, cover it with cardboard or black plastic a few weeks before you want to sow. It keeps the rain off, warms the soil a little and stops early weeds.
Pick and clear overwintered crops
Purple sprouting broccoli is often at its best in March. Keep picking the side shoots before the flowers open and it will keep producing. Leeks that have started to bolt are still usable at the base, so use them soon. Once a crop is finished, compost the healthy material; a bed cleared in March can be prepared and resown almost straight away.
Prune fruit bushes and get ahead of weeds
If redcurrants, whitecurrants and gooseberries weren’t pruned in winter, do it now: take out crossing and congested branches to leave an open goblet shape. Annual weeds such as chickweed, hairy bittercress and groundsel are young and shallow-rooted in March, so a hoe on a dry day knocks them back quickly. Perennial weeds — bindweed, couch grass, dock — are best dug out now, with as much root as you can get, before they put on growth.
Sharpen and oil your tools
Half an hour in the shed before the season starts pays back all year. Clean the blades, sharpen spades and hoes with a file or whetstone, and oil secateurs and anything with a hinge. A sharp spade takes noticeably less effort, and secateurs that cut cleanly do less damage to plants.
In the garden this month
If you have a garden as well as a plot, March is the time to cut back perennials left standing over winter, and to cut ornamental grasses to about 10cm before new growth appears at the centre. Remove old hellebore leaves to show off the flowers. Lift and divide congested clumps of hostas, hardy geraniums and sedums with two forks back to back, replanting the vigorous outer pieces and discarding the tired centre. Prune bush roses to an outward-facing bud if you haven’t already. Give the lawn its first cut, on a high setting, once the grass is growing and the ground is dry; bare patches can be reseeded once the soil has warmed, because seed sown into cold soil just sits there.
What can wait until April
Courgettes, squash, French beans and anything else frost-tender should stay off the plot for now; sown outside into cold soil they stall, and an April start catches them up. A nitrogen-rich lawn feed can wait until the grass is growing strongly, and spring-flowering shrubs such as forsythia are pruned after they finish flowering, not before.
March at a glance: early, mid and late
- Early March: walk the plot and note what needs doing; clear winter debris; chit seed potatoes; check the soil before digging; start tomatoes, peppers, aubergines, celery and leeks under cover.
- Mid-March: plant onion sets and shallots; first early potatoes on sheltered southern sites; direct sow broad beans, early peas, spinach and radishes once the soil is workable; mulch fruit; cut back and divide perennials.
- Late March: sow parsnips (fresh seed — old parsnip seed germinates poorly) and spring onions direct; beetroot under fleece; prune currants and gooseberries if not done; hoe annual weeds; plant first earlies further north once the soil has warmed; first lawn cut if the ground is dry.
Looking ahead: April and May
March is for preparing beds and starting things off indoors; April is for sowing direct and hardening off; May is for planting out and the first harvests. In northern England and Scotland the season usually runs two to three weeks behind the south. A checklist for the next two months:
- April: sow beetroot, carrots, lettuce, radishes, spinach and spring onions direct once the soil has warmed; finish planting onion sets; plant second earlies; put up bean supports before the plants need them; sow courgettes and squash in pots indoors towards the end of the month; keep sowing salads little and often, every two to three weeks.
- Hardening off: put indoor-raised seedlings outside in a sheltered spot for longer each day over a week or two, bringing them in on cold nights, and keep fleece handy if frost is forecast.
- May: after the last frost (often mid-May in the south, later in the north) plant out tomatoes, courgettes, squash, French beans and basil; plant out leeks sown in March; earth up potatoes as they grow; check for slugs after rain; keep sowing salad leaves every couple of weeks.
- First harvests: radishes are ready about four to five weeks after sowing, with early lettuce, spring onions and spinach not long after.
Resist the urge to rush: a plant started at the right time in April usually catches up with one that sat cold from February.
Where to buy seeds and plants for your March allotment
Thompson & Morgan are excellent for vegetable seeds — wide variety, clear UK growing notes, and reliable germination rates. Peter Nyssen offer quality spring bulbs and sets at sensible prices, including onion sets and seed garlic.
What to Have Ready Before You Start
Module trays and peat-free seed compost are the two things worth having before anything goes into the ground. A pack of module trays with lids costs under £10 and lasts several seasons. For seeds, Thompson & Morgan is a long-established UK seed supplier, with a variety selection that is genuinely useful for UK growing conditions.
What can I plant on my allotment in March UK?
You can sow broad beans, early peas, radishes, parsnips, and spring onions directly outdoors. Under cover, start tomatoes, peppers, lettuce, leeks, and brassicas in seed trays. Plant onion sets, shallot bulbs, and chitted first early potatoes from mid-March in milder areas.
Is it too early to dig my allotment in March?
Not necessarily, but avoid digging waterlogged soil as it damages the structure. If the ground sticks to your boots in heavy clumps, wait a week or two. Light, free-draining soils — including chalk — are usually ready to work from early March.
When should I plant potatoes on my allotment?
In the south of England, first earlies can go in from mid-March. In the Midlands and north, late March to early April is safer. The soil should feel warm to the touch and not be sodden. If frost is forecast after planting, cover emerging shoots with fleece.
You’ll find more growing guides and seasonal advice in our Garden & Outdoor.
How do I prepare my allotment for spring?
Start by clearing winter debris, turning compost, and assessing which beds need attention. Top up mulch around fruit, repair any structures, and prepare trenches for potatoes. Sow hardy crops directly and start tender crops under cover. A calm, steady approach now avoids overwhelm in April and May.
March in one sentence: Show up, do a few useful things, and enjoy the quiet before the growing season really kicks off — the plots that do well in summer are almost always the ones that were ready by the end of March.
