🫘 Broad bean
The hardiest bean there is. Sow in autumn, overwinter it, and crop a month before a spring sowing.
What the numbers mean
These are the actual parameters this game runs on. Growth is driven by growing degree days: each day contributes max(0, min(mean temp, 26) − 3), and Broad bean is ready when that total reaches 950. That is why the same seed takes a very different number of days in Dublin and in Guangzhou.
| Base temperature | 3°CBelow this, the plant accumulates no growing degree days at all. |
|---|---|
| Degree days to maturity | 950 °C·dThe heat budget it must accumulate before it is ready to pick. |
| Comfortable range | 6–22°CWhere it grows without stress. |
| Frost damage below | -6°CLeaves start taking frost damage below this low. |
| Killed below | -12°CBelow this it does not come back. |
| Heat stress above | 26°CAbove this the plant slows down and stops setting fruit well. |
| Typical time to harvest | 90–120 days |
| Yield per bed | 12 pods |
Things worth knowing
- Broad beans survive to around -6°C, one of the very few beans that can stay out all winter.
- Their root nodules fix nitrogen — dig the plants in after cropping and the next leaf crop notices.
Where and when to sow Broad bean
Pick your city to see the months when Broad bean scores well against that city's real climate records: