The Cacao Tree and the Narrowest Belt

Goal: After this lesson you can describe what cacao needs to grow and why its growing range is the narrowest of any major commodity. Subject: Geography | Run time: about 7 minutes

Quick recall

Last time we set up the episode. Two quick questions. One: what does Theobroma cacao mean? Food of the gods (Coe & Coe, 2013). Two: what was xocolatl? A bitter drink; the word means bitter water (Coe & Coe, 2013).

Why this matters

Coffee grows in a wide belt. Tea grows in a wider one. Cacao grows in the narrowest band of any major commodity, only about 20 degrees north to 20 degrees south of the equator (Coe & Coe, 2013; International Cocoa Organization, 2023). And inside that band it is even fussier than the latitude suggests, because cacao does not really want to be a farm crop at all. It wants to be a forest tree.

The idea

Theobroma cacao is what botanists call an understory tree, a tree that grows beneath a taller forest canopy rather than out in the open (Coe & Coe, 2013). It wants 50 to 70 percent shade, steady warmth between about 65 and 90 degrees Fahrenheit with no frost ever, heavy and even rainfall, and high humidity (Coe & Coe, 2013; International Cocoa Organization, 2023). Unlike coffee, it likes neutral soil, and unlike tea, it cannot take a cold season. Now the strangest part. Cacao flowers are pollinated mainly by tiny flies called midges, which live in the damp litter of a real forest floor (Coe & Coe, 2013). No forest, fewer midges. Fewer midges, less fruit. So cacao is not just a plant that tolerates the forest, it depends on the forest to reproduce. That is why growing cacao well often means growing it under a managed canopy, a practice called agroforestry. Put it together and you see why the belt is so narrow. Cacao needs a hot, wet, shaded, frost-free, low-elevation, biodiverse place near the equator. There are not many of those, and the next lesson shows where they are.

Picture it

Picture the green belt from our coffee and tea episodes, then shrink it. Coffee ran to 25 and 30 degrees. Tea ran past 40. Cacao stops at about 20 north and 20 south, a thin green ribbon hugging the equator. Now picture the plants inside it not in neat rows in the sun, but tucked in the shade under taller trees, waiting on a fly the size of a pinhead.

Remember this

The fact to carry out: cacao is the most place-bound of our commodities. It needs a hot, wet, shaded, frost-free forest near the equator, and it depends on forest midges to set fruit (Coe & Coe, 2013). That dependence on a living forest is why deforestation and climate change hit cacao so hard, which is the climate lesson coming up.

Quick check

Quick check. Cacao is an understory tree. What does that mean? It grows beneath a taller forest canopy, in shade, not out in the open sun (Coe & Coe, 2013).

Key Takeaways

Cacao grows only between about 20 degrees North and 20 degrees South, the narrowest belt of any major commodity (Coe & Coe, 2013; International Cocoa Organization, 2023).
Theobroma cacao is a forest understory tree that wants 50 to 70 percent shade, steady heat, no frost, and heavy rain (Coe & Coe, 2013).
Cacao depends on tiny forest midges for pollination, so it needs real forest biodiversity to fruit well (Coe & Coe, 2013).
Growing cacao well often means agroforestry, growing it under a managed canopy.

Sources

Coe, S. D., & Coe, M. D. (2013). The true history of chocolate (3rd ed.). Thames and Hudson.
International Cocoa Organization. (2023). Quarterly bulletin of cocoa statistics (Vol. XLIX, No. 1). https://www.icco.org