🧅 Leek
The hardiest of the onion family — it can sit in frozen ground all winter and be lifted as needed.
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, 28) − 4), and Leek is ready when that total reaches 1150. That is why the same seed takes a very different number of days in Dublin and in Guangzhou.
| Base temperature | 4°CBelow this, the plant accumulates no growing degree days at all. |
|---|---|
| Degree days to maturity | 1150 °C·dThe heat budget it must accumulate before it is ready to pick. |
| Comfortable range | 7–24°CWhere it grows without stress. |
| Frost damage below | -8°CLeaves start taking frost damage below this low. |
| Killed below | -15°CBelow this it does not come back. |
| Heat stress above | 28°CAbove this the plant slows down and stops setting fruit well. |
| Typical time to harvest | 100–130 days |
| Yield per bed | 5 plants |
Things worth knowing
- The white shaft is made by earthing soil up around the stem; the part kept from the light stays pale and tender.
- The leek is the national plant of Wales, from a story of soldiers wearing one in their caps to tell friend from foe.
Where and when to sow Leek
Pick your city to see the months when Leek scores well against that city's real climate records: