The sowing season, and the frost gauntlet.
Spring is when the Scottish growing year truly begins, but it is also the most misjudged season. Frost lingers here long after the English lowlands have warmed, and it lifts weeks apart across the country: mild coastal lowlands in late April, the north and the uplands not until late May or June. This is the season to sow generously under cover, sow hardy crops outdoors as the soil warms, and hold the tender crops back until your own last frost has genuinely passed.
Month by month
What's in season across spring
Every crop that has a sowing, planting or harvest window in any of these three months, pooled here and detailed by month in the guides above.
🌱 To sow
🌿 To plant out
Sowing, planting and harvest windows are UK-wide guidance, adjusted only so far as to never open earlier than that guidance states. They are not Scottish-specific dates: much of Scotland runs two to four weeks later than the UK guide, and later still in the north and at altitude. For timing tuned to your own garden, use the region-aware tools below.
Region-aware toolFrost Date CalculatorYour local last and first frost bands: the single most useful number for timing a Scottish season.Watch out for in spring
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.
Leek mothRHS UK timing · uncertain in Scotland
Two UK generations: May–June and a more numerous August–October flight. Mesh over alliums is again the practical control.
UK timing, and conditional in the same way as allium leaf miner; presence in Scotland is uncertain and local timing is unverified.
Carrot flyRHS UK timing · uncertain in Scotland
The avoidance model: sowing after mid-May dodges the first generation, and lifting before late August dodges the second. A 60cm fleece/mesh barrier helps whenever carrots are up.
The generation timing is the UK model; the Scottish calendar is not separately sourced. Use it as an avoidance strategy, not a dated forecast.
These 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 season 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