🥢 Yardlong bean
The bean that shrugs off high summer — the hotter it gets, the harder it sets pods.
Yardlong bean at a glance
Is Yardlong bean frost tolerant?
No. Cold hurts it even above freezing: damage starts at 4°C and it is killed below 1°C. Sow or plant it out only after your last frost.
What temperature does Yardlong bean grow best in?
It grows best between 18 and 33°C. Below 12°C it stops growing altogether, and above 37°C it slows down.
How many days does Yardlong bean take to mature?
About 60–80 days. That is a typical figure: it needs roughly 980 °C·d of warmth above 12°C, so a warm season gets it there sooner and a cool one later. The city calendars below give the sow and harvest dates for each place.
Is Yardlong bean a cool-season or warm-season crop?
A warm-season crop. It needs warm days and nights, so it goes in after the last frost, once temperatures are reliably above 18°C.
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, 35) − 12), and Yardlong bean is ready when that total reaches 980. That is why the same seed takes a very different number of days in Dublin and in Guangzhou.
| Base temperature | 12°CBelow this, the plant accumulates no growing degree days at all. |
|---|---|
| Degree days to maturity | 980 °C·dThe heat budget it must accumulate before it is ready to pick. |
| Comfortable range | 18–33°CWhere it grows without stress. |
| Frost damage below | 4°CLeaves start taking frost damage below this low. |
| Killed below | 1°CBelow this it does not come back. |
| Heat stress above | 37°CAbove this the plant slows down and stops setting fruit well. |
| Typical time to harvest | 60–80 days |
| Yield per bed | 25 pods |
Things worth knowing
- The pods reach 40–80 cm, which is exactly how it got the name yardlong bean.
- It far out-performs French beans in heat: those drop their flowers above about 32°C, yardlongs keep setting.
Where and when to sow Yardlong bean
Pick your city to see the months when Yardlong bean scores well against that city's real climate records: