You can't place small dripleaf on any block.

Put the summary of the bug you're having here

What I expected to happen was...:
The small dripleaf would have been placed.

What actually happened was...:
The small dripleaf did not get placed.

Steps to Reproduce:
1. Place a moss block
2. Then place a small dripleaf on it.
3. See you can't.
Edit = sorry for wasting time i messed up a little, you can only place it underwater.