Moisture meters are cheap, but realistically simply laying them out on cookie sheets on warm days and turning couple times a day for a week or two does the trick. I’m jealous you are have your own plants tho, I’m still working on moving to a climate that I can grow them. Then I’m many years away... I enjoyed kona coffee in kona, don’t think it was the cultivar that made it special, just the soil and weather. It was good, very smooth, but a one note number to me without the heavy body of a good Columbian, or the complexity of an Ecuadorian.