Soil temperature map

Soil temperature in the UK today

The map above is a soil temperature map for the UK and Ireland — and for the northern US and Canada — built from the same forecast models that predict the air, run for the ground. Each figure is the modelled temperature at 6cm depth, the layer that roots and seed sit in, and it is the number worth acting on: soil warms and cools far more slowly than air, so a mild afternoon moves it hardly at all while a cold week pulls it down steadily. Air temperature tells you what to wear; soil temperature tells you what the grass can do.

Today means the current model run for your area, not a reading from a probe in someone's border, and modelled figures carry that caveat openly. They are still the right tool for the decision, because what matters is the trend across the days ahead rather than the exact decimal at this moment. Every town we cover has a full page behind its dot — soil temperature, mowing windows and growth for that place, with the seeding thresholds for the grasses that grow there. Find yours on the map, or enter a postcode at the top of the page.