According to values and scale of color used, you're right, it should be soot black, but as I said, there is a range and the color scale may be different, I for one use
http://www.superslothdesign.com/chocobo/
It's a tough adjustment from grape, I was on a loop with it for a long time, but try to go slowly now. Better to do little adjustments. 3 pears and 1 berry should land you in soot black, but just in case, do one of each and see if currant purple, or 2 pears for loam brown. In either case, that would be closer and if you land in those, you know what to add next.
Again, I don't recommend the big changes now.