When using the mixer to create biomass, it simply cannot be done.

To reproduce:
Just go into a singleplayer world, set up a blaze burner, basin, mixer, and whatever you like to use to power the mixer, I just used a creative motor, since I was testing stuff in creative, and throw in your items you need to craft biomass into the basin. I tried using sticks, leaves, flowers, and mushrooms, and none of them worked. The mixer would spin, but wouldn't lower into the basin to mix the materials.

Note: There is a strange bug for me where it doesn't show the full recipe with JEI, so I may be missing an ingredient, if so, please let me know

• Mod version: createaddition+1.18.2-fabric-1.18.2-20221218a
• Fabric version: Fabric 0.14.12
• Create version: create-fabric-0.5.0g-792+1.18.2

I belive this was fixes