Why can’t/don’t we grow coffee/chocolate in green house?
Is it just cost or other factors.
In: Biology
They’re both notoriously finicky plants; it’s not just temperature (which is what a greenhouse mostly deals with). It’s temperature, humidity, wind, altitude (particularly for coffee), soil, day/night cycle, etc. A lot of those are either difficult or impossible to fix with a greenhouse.
Things like coffee and chocolate have a complex and nuanced flavor. Growing them in a controlled environment causes them to lose quite a bit of their complexity. Controlled environments are also quite expensive to build and maintain.
Producing something that is both expensive and poor quality is not a successful adventure.
Coffee can be grown in greenhouses, although it grows far better outdoors at certain altitudes with a certain temperature, light, and humidity variations. It would likely produce a poor crop or no crop in a greenhouse. Coffee is interesting in that it prefers to grow on sloped hillsides and just doesn’t like flat land.
There’s really not a big shortage of suitable farmland for coffee. However both cultivating the trees, harvesting the fruit, and processing the seeds is quite labor intensive. More so than most other crops. For various reasons the best quality is had by harvesting the berries by hand, using the pickers’ judgement. Unripe berries have poor flavor, low caffeine content, and high bitterness. Likewise if the berries are not processed, hulled, and dried with a great deal of diligence and judgement they don’t taste pleasant.
This is the reason for the high cost and less so growing difficulty of the coffee.
Cacao is a famously finicky plant. It doesn’t live long and doesn’t bear fruit in greenhouses. It requires full sun during a few hours of the day and shade during the rest of the day. It’s interesting that stops growing if it gets full sun all day or is fully shaded. It prefers partly cloudy weather most of the year. It requires more than 90% humidity all year but well drained soil with a moderate alumina clay content and pH of around 6-6.5. It also probably requires the presence of certain kinds fungi in the soil that need special soil conditions. It needs to be partially shaded by another larger tree. It is an understory tree that normally grows around clearings in rainforests.
It also needs to be pollinated by certain kinds of tropical midges. It’s possible to pollinate by hand but that’s not efficient and too often damages the flowers.
Likewise harvesting and processing the cacao nibs is a labor intensive process.
So again, “just plant it inside a greenhouse, easy peasy” doesn’t nearly do the subject of growing conditions justice.
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