Harvest and Cherry Quality

When to Pick

Coffee does not ripen all at once. On a single branch, you will find green, yellow, orange, and deep red cherries side by side. This is what makes coffee harvest fundamentally different from crops like wheat or corn -- it cannot be mechanized without sacrificing quality.

On our farms in Caicedonia, Valle del Cauca, we harvest selectively. Pickers pass through the same rows every 10-15 days during the harvest season, taking only the cherries that have reached full maturity. This is slower and more expensive than strip-picking, but it is the only way to produce coffee that consistently scores above 84 on the SCA scale.

Reading Cherry Ripeness

Ripeness assessment is both a science and a skill. I train our team to evaluate cherries on:

• Color -- fully ripe cherries are deep red (or yellow for Yellow Bourbon). Under-ripe cherries are green or pale. Over-ripe cherries turn dark purple or black.
• Firmness -- a ripe cherry yields slightly when squeezed, releasing sweet mucilage. An unripe cherry is hard; an over-ripe cherry is soft and fermented.
• Sugar content (Brix) -- measured with a refractometer. Ripe coffee cherries typically read 18-24 Brix. Higher sugar means more complex fermentation and better cup sweetness.
• Taste -- yes, we taste raw cherries in the field. A ripe cherry tastes sweet and fruity. An unripe one tastes green and astringent.

One thing I always tell visitors: grab a ripe Geisha cherry off the branch and taste it. The sweetness is remarkable -- almost like a tropical candy. That sugar is what feeds fermentation and ultimately shows up as complexity in the cup.

The Conversion Factor

One of the most important quality indicators we track is the conversion factor -- the kilograms of cherry needed to produce one arroba (12.5 kg) of parchment coffee. We track this weekly across our operations through conversion reports.

• Below 55 -- excellent cherry quality (less waste)
• 55-65 -- good, standard performance
• 65-80 -- acceptable but indicating some under-ripe or damaged cherry
• Above 80 -- poor quality cherry that needs investigation

A low conversion factor means the pickers are selecting well and the cherries are at peak ripeness. When I see the factor creeping above 65, I know something is off -- either picking discipline has slipped or weather has affected ripening. It is one of the first numbers I check every week.

What Bad Picking Costs You

When unripe cherries enter the processing stream, they create defects that no amount of roasting can fix:

• Green/immature beans cause grassy, astringent flavors
• Over-ripe beans introduce fermented, vinegary off-notes
• Broca-damaged beans (from the coffee berry borer) create dirty, musty cups
• Inconsistent ripeness reduces uniformity scores in SCA cupping

The pattern is unmistakable across our cupping data: lots harvested with strict ripeness selection consistently outscore those where picking discipline slipped. Even a 5% contamination of unripe cherry can drop a lot from the specialty threshold.

The Human Element

Selective picking depends entirely on the skill and motivation of the harvest team. We employ experienced pickers who understand that quality starts in their hands. They are trained to leave unripe cherries on the branch and return for them on the next pass -- a discipline that requires trust and fair compensation.

I have worked with some pickers for years. The best ones develop an instinct -- they can scan a branch and know exactly which cherries are ready. That kind of experience is irreplaceable, and it is why the processing step that follows can only be as good as the picking that came before it.

---

This post is part of our Seed to Cup series. Want to see real conversion factor data and harvest metrics from our farms? Join the free community at skool.com/particular-3064 where I share weekly harvest numbers and cupping results.