London in September: what to plant
Averaged over the last 5 years of daily records, September in London runs 12.2–20.2°C with about 77 mm of rain across the month. Here is what that climate actually supports.
❄️ No sub-zero nights in September in the last 5 years — frost is not the limiting factor here.
Best crops to sow now
- 🌱 Microgreens Fastest about 7 days to harvest 🪴 Windowsill pot — sheltered from outdoor weather
- 🍒 Cherry Radish about 27 days to harvest Recent mean 16.2°C — right in the sweet spot
- 🥬 Bok Choy about 41 days to harvest Recent mean 16.2°C — right in the sweet spot
- 🌿 Spinach about 42 days to harvest Recent mean 16.2°C — right in the sweet spot
- 🥗 Lettuce about 54 days to harvest Recent mean 16.2°C — right in the sweet spot
- 🍓 Strawberry about 62 days to harvest Recent mean 16.2°C — right in the sweet spot
- 🥕 Carrot about 78 days to harvest Recent mean 16.2°C — right in the sweet spot
- 🥔 Potato about 98 days to harvest Recent mean 16.2°C — right in the sweet spot
Leave these for another month
- 🌶️ Chili Pepper — Recent mean 16.2°C is too cold (ideal 18–32°C)
- 🥒 Cucumber — Recent mean 16.2°C is too cold (ideal 18–32°C)
- 🍅 Tomato — Recent mean 16.2°C — right in the sweet spot
Other months in London
Temperature and rainfall are 5-year daily normals from the ERA5 reanalysis via Open-Meteo. Suitability is scored with the same degree-day model the game runs on — it is not a generic planting calendar.