I need help with biomes

Hello, for some time I have been working on a mod where I implement a new biome, the only problem I found and I don't know how to solve it is that grass does not grow in my biome. I remember that in previous versions of MCreator there was the option "Grass per chunk", but I can't find it anymore.
I know that since 1.17 temperature, humidity and many other options have been implemented, but I don't know if they have anything to do with the growth of grass in my biome.

Note: Sorry if some words are not understood, I speak Spanish and I am using the google translator.