What to Sow and Plant in the UK Each Month: A Seasonal Checklist

The British growing year rarely follows the calendar neatly. A mild Cornish spring can race ahead of a late frost in Aberdeenshire, and a wet July can make a mockery of carefully timed sowings. What follows is a practical month-by-month guide to what to sow, plant out and harvest, with the caveat that your own soil, shelter and local weather always have the final say. Treat it as a framework, not a rule book.

January and February: The Quiet Start

January. January is for planning and protected sowing. If you have a heated propagator or a bright windowsill, sow onions, leeks, chillies and aubergines. Chit first early potatoes in a cool, light room. Outdoors, plant bare-root fruit trees, roses and hedging whenever the soil is not frozen or waterlogged. Harvest leeks, parsnips, kale, winter cabbage and sprouts. Force rhubarb by covering crowns with a bucket. Check stored onions, squash and apples for rot.

February. February often brings the first real sowing window. Under cover, sow tomatoes, peppers, aubergines, cucumbers and celery. Outdoors, if the soil is workable, sow broad beans, peas, spinach, radish and early carrots. Plant out onion sets, shallots and garlic if you did not plant in autumn. First early potatoes can go in at the end of the month in milder areas. Harvest purple sprouting broccoli, leeks, winter salads and the last of the parsnips. Prune apples and pears while dormant.

March and April: The Engine Room

March. March is the month when everything starts to move. Direct sow carrots, beetroot, parsnips, lettuce, spinach, chard, peas and broad beans. Under cover, sow tomatoes, peppers, cucumbers, courgettes and squash. Plant out onion sets, shallots, early potatoes and strawberry plants. Harvest spring greens, purple sprouting broccoli, rhubarb and overwintered salads. Keep an eye on slugs; they wake up hungry.

April. April is for main sowings and hardening off. Direct sow carrots, beetroot, radishes, lettuce, spinach, chard, peas, mangetout and broad beans. Sow sweetcorn, courgettes and squash under cover. Plant out maincrop potatoes, brassicas and leeks. Harden off greenhouse-raised plants before planting out. Harvest asparagus from late April, plus rhubarb, spring onions and cut-and-come-again salads. Watch for late frosts; keep fleece handy.

May and June: The Great Outdoors

May. May is the traditional planting-out month, but wait until the last frost has passed in your area. Sow runner beans, French beans, sweetcorn, courgettes and squash outdoors. Keep sowing salads, radish, beetroot and carrots in small batches. Plant out tomatoes, peppers, aubergines and cucumbers under cover, and courgettes, squash, sweetcorn and beans once hardened off. Harvest asparagus, early potatoes, strawberries, peas, broad beans and salad leaves.

June. June is for succession and winter planning. Sow French beans, runner beans, beetroot, carrots, lettuce, radish and spinach for autumn. Sow winter brassicas, kale, purple sprouting broccoli and leeks. Plant out sprouts, cabbages, sweetcorn and squash. Harvest strawberries, raspberries, broad beans, peas, new potatoes, courgettes, cucumbers and salads. Water deeply and mulch to lock in moisture. Stake tall crops before the wind does it for you.

July and August: Peak Harvest

July. July is about keeping crops happy and sowing for later. Sow salads, radish, spinach, chard, beetroot and carrots for autumn and winter. Sow spring cabbage, winter kale and turnips. Plant out leeks and winter brassicas. Harvest tomatoes, courgettes, beans, cucumbers, potatoes, onions, garlic and soft fruit. Feed tomatoes and peppers regularly. Remove side shoots from cordon tomatoes.

August. August is the month to fill gaps and prepare for winter. Sow overwintering salads such as corn salad, land cress, winter radish and spring onions. Sow green manures on empty beds. Plant out spring cabbage and kale. Harvest maincrop potatoes, onions, garlic, tomatoes, beans, courgettes, sweetcorn and early apples and plums. Prune summer-fruiting raspberries after fruiting. Keep picking beans and courgettes to encourage more.

September and October: The Turning Point

September. September is for harvest and winter preparation. Sow winter salads, spinach, rocket and broad beans for overwintering. Plant out winter cabbage, kale and leeks. Harvest apples, pears, plums, squash, pumpkins, maincrop potatoes, onions, garlic and beans. Clear spent crops, sow green manure and start collecting leaves for leafmould.

October. October is planting time for next year. Plant garlic, onion sets, broad beans and overwintering peas. Plant bare-root trees, shrubs, roses and hedging as the soil is still warm. Sow winter salads under cover. Harvest apples, pears, quince, squash, leeks, kale, parsnips and celeriac. Mulch empty beds and protect tender plants. Clean and store tools.

November and December: Harvest and Plan

November. November is for bare-root planting and final harvests. Plant bare-root fruit trees, roses, hedging and bulbs if you have not already. Plant garlic and broad beans. Sow winter salads under cover. Harvest leeks, parsnips, kale, Brussels sprouts, winter cabbage and celeriac. Prune apple and pear trees, clean the greenhouse and insulate pots.

December. December is quiet, but not empty. If the soil is workable, plant bare-root trees and shrubs. Sow winter salads under cover or on a bright windowsill. Harvest leeks, parsnips, Brussels sprouts, kale and winter salads. Order seeds, plan rotations and service tools. Use the slower weeks to note what did well and what you would change.

A Workable Year-Round Rhythm

Climate, soil and shelter vary enormously across the UK. A south-facing wall in London can be weeks ahead of an exposed allotment in Yorkshire. Use this checklist as a prompt, then adjust. The best guide is your own soil and the weather forecast.

Three habits make the monthly checklist work:

• Sow little and often: a short row of salad every fortnight beats one giant sowing that bolts.
• Harden off gradually: move plants outside for a few hours each day before planting out.
• Keep a notebook: record sowing dates, first harvests and failures. Your own notes will soon outrank any generic guide.

If you garden on heavy clay, wait for it to dry before sowing; on light sand, water and mulch more often. And when a cold snap is forecast, fleece, cloches and a little patience will save more than any rushed sowing.

Photo: Micheile Henderson / Pexels