Little thinks that this slow ripening may have been what happened with his indoor coffee, possibly improving the taste. It just so happened that Little"s office also provided some other key climatic conditions for coffee growth. "The average temperature for coffee growth is 19C," he says. "It"s not like some tropical crops that need heat and humidity, so our office is about right. It never freezes, never falls below 19C in winter in the daytime: perfect for a coffee tree. In terms of humidity, the UK is about 60-80%. It"s not perfect but it is not far off."