I see. The picture looks exactly like mine...but I don't know if it is. It wasn't that expensive.
I made a drink last night with cucumber, chard, parsley and wheat grass...with a splash of apple juice. No cubes, but I have used cubes before...and/or frozen fruit.
It had a little trouble getting started but I just added a bit more juice and then it was fine. Liquified everything in the blink of an eye...and the drink was smooth and delish. (I didn't strain this, I drank it whole. I will only strain when fasting.)
I do use my VM dry to chop carrots when I make dog food, but other than that I always add liquid.
I can see where it might be difficult with just grass and cubes.