ALTITUDE, SOIL, AND RAINFALL: WHY WHERE COFFEE GROWS CHANGES EVERYTHING
Bean Knowledge — 1 July 2026
Coffee is an agricultural product. Like wine, its flavour is shaped by the conditions in which it grows. Here is what terroir means in coffee — and why it matters.
The word terroir comes from wine. It refers to the complete natural environment in which a grape is grown — the soil, the climate, the topography, the microorganisms — and the way that environment expresses itself in the flavour of the wine. Coffee has terroir too, and understanding it is the key to understanding why coffees from different origins taste so different.
Altitude is the most significant single factor in coffee quality. Coffee grown at high altitude — above 1,500 metres — develops more slowly than coffee grown at lower elevations. The cooler temperatures and lower oxygen levels slow the ripening of the cherry, giving more time for the plant to develop the sugars, acids, and aromatic compounds that produce complex flavour. High-altitude coffees are typically brighter, more acidic, and more complex than their low-altitude counterparts.
The relationship between altitude and quality is not absolute — other factors matter too — but it is consistent enough that altitude is one of the primary criteria used by specialty buyers when evaluating potential lots. The coffees that score highest on the SCA quality scale almost always come from high-altitude growing regions: Yirgacheffe in Ethiopia (1,700 to 2,200 metres), Huila in Colombia (1,500 to 2,000 metres), the highlands of Guatemala (1,500 to 1,800 metres).
Soil composition affects flavour in ways that are less well understood but clearly significant. Volcanic soils — found in regions like Sumatra, Guatemala, and parts of Colombia — are rich in minerals and have excellent drainage properties. They tend to produce coffees with distinctive earthy, full-bodied character. The red clay soils of Kenya's Central Province are associated with the intense blackcurrant and tomato notes that define Kenyan specialty coffee. The organic-rich soils of Yirgacheffe contribute to the floral, tea-like quality of the region's best coffees.
Rainfall patterns determine the timing and consistency of the harvest. Coffee requires a distinct dry season to trigger flowering, followed by sufficient rainfall during the development of the cherry. Regions with well-defined seasons — like Colombia's Huila, which has two distinct harvest periods per year — can produce more consistent quality than regions with less predictable rainfall. Irrigation can compensate for inconsistent rainfall, but it is expensive and not available to most smallholder farmers.
Temperature variation between day and night — diurnal variation — is another key factor. In high-altitude growing regions, the temperature can drop significantly at night, slowing the metabolism of the coffee plant and concentrating the compounds that produce complex flavour. This is one of the reasons why the best coffees in the world come from equatorial regions at high altitude: the combination of tropical sunlight and cool nights creates ideal conditions for slow, complex cherry development.
When you taste the floral brightness of an Almond Blossom or the dark intensity of a Starry Night, you are tasting the accumulated effect of all these factors: the altitude, the soil, the rainfall, the temperature. You are tasting a place.