I am trying to model a grass stalk and I want the bottom part to be brownish-yellow and the top part to be fresh-green. All I know is that we have to select regions from the mesh and assign different colors to them, but this method will not make it realistic. It will look odd. I want those two colors to merge in the middle. I think you know what I mean.
I want it like this: you can see the different colors and they are merging in the middle: