About
When to plant is a calendar for people growing vegetables and fruit in the UK. It answers a practical question: what can I sow, plant out or harvest this month, where I live.
Why a UK calendar
A lot of planting advice online is written for the United States. Those frost dates and variety lists do not match a British spring, which is long, damp and very different from Cornwall to Caithness.
The month pages and crop guides on this site follow published UK guidance, chiefly from the Royal Horticultural Society and BBC Gardeners' World. Figures for spacing, depth and timing are taken from those sources and cited on the page. They are not guessed.
What the dates can and cannot tell you
A month is a window, not a promise. Soil temperature, a late frost and a wet clay bed all move the right day. The frost page shows how far those windows shift between regions, using Met Office air-frost averages and RHS planting-out advice.
This is general guidance for home gardeners. It is not a forecast, and it is not a substitute for the instructions on your seed packet.
How the site is put together
The pages are generated from data files: one for each month, one for each crop, plus a single list of kit that can later carry shop links. New crops can be added without rebuilding the design.