Hey Lendrick! Nice start on these tiles. Your dirt looks excellent.
But hmm, the grass seems too noisy. If anything, I'd have bigger strands. Get a few, well-defined blades, and draw over them. The less noise, the easier it is for it to be read, and the nicer it is for you to tile it. Your dirt doesn't look near as noisy, on the other hand, which is good.
Also, the transitions at the edge of the grass look like they need a lot more attention. Your bottom shadows on the grass transition are too small.
The strands at the "top" of your grass have blades which don't really make sense. There's only highlights at the top of the blade, and it makes it look like the grass doesn't actually poke out, because there's not enough elevation.
The colors for the grass pretty much work, I'd probably use another highlight color on that.
Also the plant on the grass seems really out of place. Now it's TOO saturated, whereas before it wasn't contrasting enough. I would draw the plant as a separate image before trying to merge it entirely with the grass, but keep its surroundings' palette in mind.
So yeah, the grass as it is needs a lot of reworking, sadly. It might be easier to start over than to clean up all the noise. I don't know.
Keep at it though!