I'm gonna assume that you're talking about bubble hash, where you put the plant in water filled with ice cubes.
I only use dry plants for that.. You'll get a lot of chlorophyll into your hash, if you use wet plant material, and chlorophyll tastes like garbage.
- Also.. The more chlorophyll, the more green the hash will be.
Some people say to freeze it fresh instead. so you could do that if you want.. But I really don't like the taste of chlorophyll, so I dry it, to get as much chlorophyll out of the leaves and buds as possible, before I start..