I have put veggies in my blender. I usually use the leftover cooked veggies we had for supper the night before and mix them will almond milk, some berries, protein powder, psyllium, etc. I did learn not to mix too many at once. It gave me horrible gas.
I'd experiment and see what works best for you. However, start with small amounts. As mentioned before, we are all unique and therefore tolerate things differently.