🌿 Amaranth greens
A true summer green: it thrives in the heat that shuts every other leaf crop down.
Amaranth greens at a glance
Is Amaranth greens frost tolerant?
No. Cold hurts it even above freezing: damage starts at 2°C and it is killed below 0°C. Sow or plant it out only after your last frost.
What temperature does Amaranth greens grow best in?
It grows best between 16 and 32°C. Below 10°C it stops growing altogether, and above 36°C it slows down.
How many days does Amaranth greens take to mature?
About 30–45 days. That is a typical figure: it needs roughly 550 °C·d of warmth above 10°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 Amaranth greens 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 16°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, 34) − 10), and Amaranth greens is ready when that total reaches 550. That is why the same seed takes a very different number of days in Dublin and in Guangzhou.
| Base temperature | 10°CBelow this, the plant accumulates no growing degree days at all. |
|---|---|
| Degree days to maturity | 550 °C·dThe heat budget it must accumulate before it is ready to pick. |
| Comfortable range | 16–32°CWhere it grows without stress. |
| Frost damage below | 2°CLeaves start taking frost damage below this low. |
| Killed below | 0°CBelow this it does not come back. |
| Heat stress above | 36°CAbove this the plant slows down and stops setting fruit well. |
| Typical time to harvest | 30–45 days |
| Yield per bed | 6 bunches |
Things worth knowing
- Amaranth is one of very few leaf crops that keeps producing through high summer, when most greens bolt above 30°C.
- Red amaranth turns its cooking water deep magenta — the same betalain pigment that colours beetroot.
Where and when to sow Amaranth greens
Pick your city to see the months when Amaranth greens scores well against that city's real climate records: