While specialty coffee “elevates” our coffee experience every day, many folks don’t know why the elevation of a farm might be shared on a coffee bag or profile. Today, we’ll get “high” on the impact of elevation on coffee: How it’s grown, how it’s roasted, and — of course! — how it tastes.
When you see the elevation of a farm (or mill) on a coffee bag, what that means is how high above sea level that particular parcel of land or fixed geographical point is. It’s often listed in either meters above sea level (sometimes written as MASL) or in feet, though the latter is less commonly found in coffee. Often, the elevation is written as a range, starting from the lowest point of the farm or the group of farms and extending up to the highest: For example, a coffee that is blended from lots grown by many different producers in Colombia might be listed as having an elevation of 1,200 to 2,000 meters, accounting for the variety of the farms represented in the blend. Or a single-farm lot might have an elevation of 1,800 to 1,850 meters, accounting for the slope of the individual property.
Why does elevation matter?
Arabica coffee, the kind that we associate with high-quality flavors in the cup, is a sensitive tropical plant that thrives in specific environments: It loves a rainy season and needs one in order to start flowering (but not too much rain); it loves warm and sunny days during gestation and maturation (but not too hot); and cool overnight lows will help with developing those sweet and fruity flavors both on the plant and in the post-harvest processing (but no frost, please!).
All of this combines to mean that Arabica thrives in high-elevation environments because, as author Robert W. Thurston explains, “Altitude is in effect a temperature variable.” Terroir located farther from sea level is typically cooler than terroir closer to sea level, and those cooler temperatures can cause coffee plants to produce denser seeds (beans) than ones grown in warmer areas. This is caused in part by the fact that the plants tend to produce fewer seeds overall, diverting more of their nutrient resources to the ones that do develop. It’s also caused by the fact that cooler temperatures mean longer, slower gestation periods: The plants, their blossoms, and their seeds take longer to mature, often producing only one crop annually. (We’ll come back to this density point in a moment.)
Higher-elevation coffees, as a result, have the potential to be fruitier and more floral, with nuance, sparkle, and more articulate flavors than, say, the same coffees planted at lower elevation. When we think about high-elevation coffees, we imagine the delicate jasmine and lemongrass of a washed coffee from 2,000 to 2,200 meters in Yirgacheffe, Ethiopia, or the juicy red fruit and sugar-cane sweetness of smallholder lots from 2,200 to 2,300 meters in Nariño, Colombia.
We’re not saying that low temps and slow maturation are the only way to grow quality coffee — and lots of farmers have found ways to grow fantastic crops lower down. In fact, farmers at lower elevation may be able to simulate the effect of vertical distance by planting extra shade trees, which can keep it significantly cooler over their coffee farms and encourage slower maturation and development. Some varieties actually prefer lower elevation, and really shine when they are allowed to thrive there; some coffees will experience “die back” when planted too high up.
In other words, your mileage — and your meters above sea level — may vary.
One of many variables
One of the main reason that farm elevation isn’t the only marker of high quality is that there are myriad variables in creating a fantastic cup: Not only the elevation of the farm, but its soil quality, the varieties planted there, how ripe the coffee is picked, how expertly it’s processed, how it was stored, how quickly it shipped, how and when it was roasted... and don’t even get us started on brewing!
Elevation is one part of the 1,000-piece puzzle that comes together just right in order to express beautiful, truly special coffees. Even still, for many producers, traders, roasters, and coffee drinkers, it offers a significant clue about the potential of a coffee.
In some producing countries, elevation is used to establish the standardized grades that are assigned to every lot that leaves as export: In Guatemala, for example, the highest quality grade for commercial coffee is SHB (or Strictly Hard Bean), which is reserved for coffees grown at or above 1,370 meters. In El Salvador, the highest grade is SHG or Strictly High Grown, coffees from farms at or above 1,200 meters. These classifications, while helpful for writing contracts, don’t necessarily correlate with flavor, but rather with physical characteristics that can be measured without tasting.
Another thing to consider is that farming coffee at high elevations is really, really hard: Imagine simply walking along a slope at 1,800 meters — and now imagine walking along that same slope while picking and carrying nearly 100 kilograms of coffee cherries! Harvesting coffee is no easy work even on level ground, but adding a slant to the land itself can mean fewer passes through the trees to pick ripe, and it can also make it difficult to apply fertilizer, prevent erosion, and protect the plants against wind and rain.
Elevation and roasting
Remember that bit about bean density above, and how high-elevation farms tend to produce denser coffee seeds? This is actually very significant for a coffee roaster, who will often use bean density as a way of determining how to approach the design of a roasting curve. Scott Rao writes in The Coffee Roaster’s Companion, “For a given bean size, it requires more energy to penetrate the core of denser beans.” This means that the roast master may need to hit the coffee with a higher temperature in the roasting machine, and they need to consider this temperature as they design both the individual process and their order of operations for the day.
For this reason, the elevation classification for a particular lot is important information for a roaster to have, as a piece of starting information to help them consider the best way to approach and express a coffee. For anyone who is particularly interested in the art and craft of roasting, elevation is a fun and fascinating topic of conversation!
Elevation versus altitude: a note for the word nerds
You may see the word “altitude” used synonymously with “elevation” on coffee packages and in marketing, and in fact, you may even see it more commonly. While both words do refer to a measurement of “height” in some way, they differ slightly: Altitude is the measurement of vertical distance of something above sea level, such as a plane flying through the sky, while elevation is the measurement of distance from sea level on land.
Why “altitude” gets used more often is anybody’s guess — and quite honestly, I’m not sure it really matters — but there you have it. Feel free to use this fact at your next coffee-trivia night.
Noticing the elevation at which a particular coffee was grown can not only give you a clue about its complexity, quality, and overall flavors, but it may also give you a small glimpse into the life those beans lived before they arrived in your mailbox.
The next time you brew a high-elevation coffee, imagine the crisp mountain air, the low-hanging clouds, the hard work of the pickers’ expert hands, and the amazing topographical diversity of the places on earth that grow these beans we love so much. If that doesn’t send you soaring, we don’t know what will.