RHS H2 UK planting calendar
When to plant peas in RHS H2 (UK)
Sowing, planting, and harvest dates calibrated to H2's 250-day UK season (Isles of Scilly, Channel Islands, the warmest sheltered pockets of west Cornwall and south Devon).
Key dates for peas at RHS H2
| Stage | When | Anchor |
|---|---|---|
| Direct sow outdoors | early February (8 February) | 35 days before last frost (mid-March (Scilly Isles, Channel Islands)) |
| First harvest (estimate) | mid-April (14 April) | ~65 days from sow |
Dates are typical for the regions H2 describes (Isles of Scilly, Channel Islands, the warmest sheltered pockets of west Cornwall and south Devon). UK frost pockets, urban heat, and coastal moderation can shift the planting window by 1-2 weeks within the same rating band. Always cross-check against your local Met Office station for current conditions.
Why this timing works at H2
H2 describes UK gardens with winter minima of minimum 1-5 °C. Last spring frost typically passes mid-March (Scilly Isles, Channel Islands); first autumn frost arrives late November, giving about 250 frost-free days. Peas prefer the cool damp weather UK springs and autumns deliver — they bolt and turn bitter once daytime temperatures climb above 24 °C, which makes the British shoulder seasons their happiest time.
Peas are the classic early-spring crop — direct-sow 4-6 weeks before the last spring frost, as soon as soil can be worked. They quit producing once daytime temperatures consistently hit 24 °C, so the sooner they go in, the longer the harvest window.
UK-specific tips for H2
- Peas grow well outdoors in the Scilly Isles and Channel Islands but are still vulnerable to occasional spring frosts — keep horticultural fleece to hand through April.
- Slug pressure is severe in mild damp winters — start beer traps and copper rings in March, not when you see damage.
- Wind exposure trumps temperature in H2 coastal pockets. Salt-laden gales burn foliage as quickly as any frost — establish a windbreak before you plant.
Quick-grow guide
- Sun: Full sun in cool weather (most UK summers qualify).
- Soil temperature for germination: 7-24 °C (45-75 °F).
- Spacing: 2-3 inches (5-8 cm).
- Days to harvest from direct sow: ~65 days.
- Sow in cool conditions — UK springs and autumns are ideal. Provide some afternoon shade if a heatwave arrives in July.
Common mistakes — H2 × peas
- Sowing too late: peas bolt in heat — UK Junes can spike to 28 °C, so the productive window is March-May and again August-October at rating H2.
- Ignoring slug pressure: damp UK springs are slug heaven. Protect rows with copper tape or wool pellets, or sow into modules and transplant when seedlings have toughened up.
Source and methodology
RHS hardiness rating thresholds from the official RHS reference. Typical frost-date averages from Met Office regional climate summaries for the geographies H2describes. Crop timing offsets calibrated against UK extension references (RHS sowing calendar, Garden Organic, James Wong's UK growing tables) and cross-checked against US Cooperative Extension Service publications. For American readers cross-referencing, RHS H2 is roughly equivalent to USDA zone 10. Curated by the Growli editorial team.
Keep going
- How to grow peas — full guide
- RHS H2 — typical regions and what else to plant
- All RHS hardiness ratings (H1a-H7)
- USDA hardiness zones — for cross-reference with US sources
- Fungus gnats in UK houseplants — guide