Growing Conditions · Wales
Gwynedd Growing Conditions
Soil, hardiness and a planting calendar for Gwynedd — across 10 postcode districts.
Soil
The soil most gardeners wish for: a free-draining, slightly acid loam that warms early in spring and rarely waterlogs. It suits the widest range of planting — vegetables, perennials, shrubs and trees — and asks little beyond an annual mulch to keep its structure. Because it drains freely it can dry in a hot summer, so new plants, pots and lawns benefit from steady watering through July and August. For patios, paths and walls its stability makes for straightforward foundations.
Winter hardiness
A mild area rated RHS H3 — winters usually bottom out around -4°C. Most hardy plants are safe, and you can grow half-hardy exotics that fail further north, but the occasional hard frost means tender plants still want a sheltered wall or winter fleece.
Rain & growing season
A very wet climate (1305mm a year) — drainage is the priority, moisture-loving planting thrives, and paving and lawns must be laid to drain. A long growing season (~358 frost-free days) — you can sow earlier and harvest later than most of the country, and squeeze in a second late sowing.
Planting Calendar for Gwynedd
The long season allows a second sowing of quick crops in July.
Timings are guided by this area's ~358 frost-free days and RHS H3 hardiness; adjust for a cold or sheltered garden.
Conditions by Postcode
| Postcode | Soil | Hardiness | Rainfall |
|---|---|---|---|
| LL37 | free-draining acid loam — the classic 'good garden soil' | RHS H4 | 1397mm |
| LL40 | acid clay loam, seasonally wet | RHS H4 | 1397mm |
| LL41 | shallow, free-draining acid loam over rock | RHS H4 | 1397mm |
| LL49 | coastal flat soil, high water table, some salt | RHS H3 | 1371mm |
| LL53 | light, fast-draining sandy soil | RHS H3 | 1371mm |
| LL54 | free-draining acid loam — the classic 'good garden soil' | RHS H3 | 1371mm |
| LL55 | acid clay loam, seasonally wet | RHS H3 | 1220mm |
| LL56 | free-draining acid loam — the classic 'good garden soil' | RHS H3 | 1220mm |
| LL57 | free-draining acid loam — the classic 'good garden soil' | RHS H3 | 1090mm |
| LL59 | free-draining acid loam — the classic 'good garden soil' | RHS H3 | 1220mm |
Planning work in Gwynedd?
Browse Companies House-registered landscaping businesses in the area.
