What to Do on Your Allotment in January

January is the month most allotment holders dread — cold soil, short days, and very little to harvest. But it is also the most valuable planning month of the year. What you do (and decide) in January shapes everything that follows.

What to sow in January

Indoors (heated propagator or warm windowsill): - Onions and leeks from seed — they need a long growing season and should be started as early as late January. Sow thinly in trays of multipurpose compost. - Broad beans can be started in root trainers indoors in late January if you want an early head start.

Outdoors: - In mild areas (particularly the south and west), garlic planted in autumn will already be showing green shoots. No action needed. - Broad beans can be sown directly in milder regions under cloches if you haven't started them indoors.

What to harvest in January

• Leeks — pull as needed throughout winter
• Parsnips — flavour improves after frost as starch converts to sugar
• Brussels sprouts — pick from the bottom of the stalk upwards
• Kale and cavolo nero — pick young leaves regularly for best flavour
• Chard and winter spinach — cut and come again, protected from hard frost

Key jobs for January

Chit seed potatoes. Buy certified seed potatoes now and lay them in a cool, light, frost-free spot (a spare room or greenhouse shelf) with the "rose end" (the end with most eyes) facing up. By March they will have short, sturdy green shoots ready for planting. This is one of the highest-return 10 minutes you spend all year.

Force rhubarb. Place an upturned bin, bucket, or purpose-made forcer over an established rhubarb crown to exclude light. The plant will produce sweet, tender pink stems 4–6 weeks sooner than open-grown crowns. Remove the cover after harvest to let the plant recover for the rest of the season.

Plan your crop rotation. Draw your beds on paper (or in a planning app like RootPlan) and decide which crops go where. A simple 4-bed system groups brassicas, legumes, root vegetables, and alliums into separate beds that rotate one space each year. This interrupts pest and disease cycles and reduces the need for sprays.

Dig and improve empty beds. If your beds are not under green manure or mulch, now is a good time to dig in well-rotted compost or manure. Avoid digging waterlogged soil — you compact it and destroy structure. Wait for a dry spell.

Sharpen and oil tools. Clean spades, hoes, and secateurs. A sharp hoe makes a huge difference to weeding speed in spring.

Pests to watch

• Slugs are inactive but sheltering in debris, under stones, and in the top layer of soil. Clearing rough patches now removes overwintering habitat.
• Birds — pigeons will strip any brassica leaves they can reach. Net your kale and Brussels sprouts if not already done.
• Mice — if you have stored onions, garlic, or squash in a shed, check regularly. Mice target bulbs and seeds.

Quick win: order seeds now

Seed catalogues arrive in December and January. Popular varieties — particularly heritage tomatoes, unusual squash, and sought-after potato varieties — sell out by February. Order now rather than being disappointed in March.