The busiest sowing month. Hold the tender crops back a little longer.

The month ahead

April is the month everything starts moving. Soil is workable across most of the country, the days are noticeably longer, and there is more to sow than any other month of the year. It is also the most deceptive month ; a warm, sunny week can convince you the frosts are done, and then a clear night in late April will blacken every tender plant you put out too early. More Scottish gardeners are caught by April frost than any other month.

Start hardening off any plants raised indoors. Stand them outside during the day and bring them in at night for a week, then leave them out in a sheltered spot for a few more days before planting. Sow sweetcorn and outdoor cucumbers under cover for planting out in June. Sow quick crops of radish and salad leaves between slower rows.

Trays of young seedlings standing outside on a garden table during the day as part of hardening off
Outside during the day, in at night for a week, then left out a few more days before planting.

What to do in April

Sow indoors

Under cover: windowsill, heated propagator or greenhouse.

Sow outdoors

Direct into prepared ground (or under a cloche/fleece where noted).

Plant out

Move transplants, sets, tubers or cloves into their final spot.

Harvest

Ready to pick or lift this month (windows are approximate).

Fruit

Weed thoroughly around fruit bushes and canes now, before the weeds set seed. One hour spent weeding in April saves ten hours in July. Mulch around strawberries, raspberries and currants with well-rotted compost. Tie in new growth on climbing plants and put supports in place early ; it is always harder once the plant has grown through them.

Key jobs in April

  • Sow hardy crops outdoors: carrots, beetroot, salad, spinach, peas, kale.
  • Plant maincrop potatoes and onion sets.
  • Sow courgettes and beans indoors, ready to plant out after the last frost.
  • Harden off any plants raised indoors before they go outside permanently.
  • Start earthing up early potatoes as shoots emerge.
  • Sow sweetcorn and outdoor cucumbers under cover for planting out in June.
  • Weed thoroughly now. One hour now saves ten in summer.
  • Keep fleece to hand: a clear night can still bring a damaging frost inland.
  • Tie in new growth on climbing plants and put supports in place early.
  • Sow quick crops of radish and salad leaves between slower rows.

The Scottish picture this month

Growth accelerates and soil is workable across most regions. Frost risk is easing on the coasts but very much alive inland and up high. A late cold snap catches more Scottish gardeners in April than any other month.

Frost: Mild lowlands (Central Belt, Highlands coast, Southwest, Islands) reach their last-frost band late April; the Northeast, Borders and all upland areas run into May.

Region-aware toolFrost Date CalculatorYour local last and first frost bands: the single most useful number for timing everything above.

Watch out for

Damping off

Seedlings started under cover in cold, low light are prone to collapsing at the base. It is tied to early-spring propagation, exactly when Scottish growers start sowing indoors.

Vine weevil (larvae)

The lethal stage: grubs eat roots from autumn to spring, worst in pots and containers. Check the roots of any plant that wilts for no clear reason.

Allium leaf minerRHS UK timing · uncertain in Scotland

Two egg-laying periods on alliums: March–April and late summer–autumn. Covering leeks, onions and garlic with fine mesh over those windows is the main defence.

UK timing, and conditional: the pest may not be established across all of Scotland, and where it is, Scottish generations have consistently lagged the UK ones. Treat these as a UK guide, not a Scottish forecast.

Mint rustbroad seasonal window

Symptoms can appear from spring until autumn. Cut affected mint to the ground and never propagate from infected plants.

Timing is broad, close to "the whole growing season", so treat it as a standing watch rather than a monthly alert.

These problems track the weather, not the calendar. Their month-by-month activity isn't sourced, so we tie them to the conditions that trigger them rather than pretend a date:

Slugs & snails

Watch when: mild, wet, damp conditions, worst around soft young growth

Activity tracks moisture and temperature, so risk climbs in any mild damp spell. Pressure is highest on tender seedlings in spring and again in a wet autumn.

Sources
  • RHS: grow-your-own guides: sowing, planting and harvest timing for all 25 crops (each window hand-derived from the crop's own RHS prose)
  • GrowScotland: pest activity framing: which pests to flag each month is our own reading of RHS activity data. We surface only what RHS sources, and frame weather-driven diseases by trigger conditions rather than inventing a Scottish calendar