What to Do on Your Allotment in April

April is when the allotment hits full swing. The soil is warm enough for a wide range of direct sowings, first early potatoes need earthing up, and the greenhouse or windowsill is full of seedlings hardening off for the outside world.

What to sow in April

Indoors: - Runner beans and french beans — can be started in 8cm pots. They germinate quickly and will be ready to plant out after the last frost in mid to late May. - Tomatoes — last chance for a good season. Later sowings still produce well with a long, warm summer. - Courgettes and squash — if not already started.

Outdoors (from early April): - Beetroot — sow in rows, thinning to 10cm when seedlings appear. - Carrots — second sowing under fleece. - Swiss chard and leaf beet — both are reliable and productive. - Peas — continue succession sowings every 2–3 weeks. - Lettuce, rocket, and salad leaves — ideal conditions for both. - Turnips — fast-growing, sow direct.

What to harvest in April

• Asparagus — if your bed is 3+ years old, spears will start to emerge from mid-April. Cut when spears are 15–20cm tall.
• Purple sprouting broccoli — final flushes.
• Spinach and spring onions — overwintered plants will be mature.
• Radishes — first March sowings are ready now.

Key jobs for April

Earth up potatoes. As shoots emerge, draw soil up over them with a hoe to form a ridge. This protects from late frosts, increases tuber formation, and prevents greening. Repeat every 10–14 days.

Plant asparagus crowns. If you're establishing a new bed, April is the ideal time. Dig a 20cm deep trench, mound the centre, and drape crowns over the mound with roots hanging down. Cover with soil and water. Do not harvest for at least 2 years — patience pays back for 20+ years.

Harden off tender seedlings. Start moving courgettes, tomatoes, and other tender plants outside during the day, bringing them back in at night. Do this for 1–2 weeks before planting out. Skipping this step leads to transplant shock.

Weed aggressively. April is peak annual weed germination. A hoe pass every week keeps them in check before they set seed.

Pests to watch

• Cabbage white butterflies start flying in April. Net all brassicas if not done.
• Carrot fly — the first generation starts looking for carrots in April. Sow in raised beds with a 60cm fine mesh barrier around them, or use fleece.
• Slugs and snails — still very active, especially after rain.

Quick win: plant what you bought at the garden centre

Many people buy bedding plants, vegetable plugs, or potato sets in April but leave them sitting in packaging. Get them in the ground or properly potted up within a day or two of buying — plants sitting in small bags deteriorate quickly.