According to the Wiki:
https://rats-mod.fandom.com/wiki/Ratlantis

I should be able to grow ratglove flowers by putting bonemeal on grass in Ratlantis.

This is not working for me and I am just growing regular grass.

I am on Minecraft 1.15.2
Forge 31.2.29
Rats 5.3.2

Fixed in 5e55839

Same problem

Minecraft 1.16.4
Forge 35.1.13
Rats 7.0.1-1.16.3
Ratlantis 1.0.0-1.16.3

Modpack Allthemods 6-1.3.7