Nyeri and Kirinyaga are definitely the most popular counties for traders and roasters in origin. As a consequence of the above, they are also the ones that obtain the highest prices in the auctions of the Nairobi Coffee Exchange.
And the answer is not as obvious as you might think.
Let's look at the altitude, the average range of altitude in the cultivated areas is higher in Kiambu with 1860masl, followed by Nyeri with 1760m and Kirinyaga with 1605m.
Rain patterns. In the three counties are also similar, there are bimodal rain patterns which brings two wet seasons a year (therefore 2 flowerings and two harvests a year), with annual rainfall averages of 953 mm for Nyeri, 1098 mm for Kiambu and 1518 mm for Kirinyaga .
The composition of the soils is similar in all three counties. They are all red volcanic soils, rich in nutrients and organic matter.
And the processing method, exactly the same, fully washed process with double fermentation and sundried on African beds.
From the above we can conclude that the success of the "trademark" Nyeri and Kirinyaga in detriment of Kiambu, is due exclusively to a matter of quantity and therefore overexposure in international markets, and not to the potential to produce quality. From a macro perspective, the various factors influencing high quality production are virtually identical in all three counties.
To finish, just say that it is undeniable that in Nyeri and Kirinyaga there are exceptional lots, but they are also in Kiambu; It's just a matter of seek, discover and blind cupping!
Enjoy your coffee ... from Kiambu