We have smoothies pretty much every day. You can throw a handful of any fresh greens in there and it won't really change the flavor. Baby spinach is very tender and will disappear the most. Kale is tough and will change the texture, if not make it a bit chewy. Most people who like green smoothies swear by frozen berry blends and say that they go best with the tougher greens. I just chuck a handful oh spinach into anything and everyone, including Hubs, drinks it right up. We almost always start with a banana and add things like mango and peach, strawberries and watermelon, avocado and sometimes red grapes for sweetness. So far for veg we've tried spinach, baby spinach, kale, peas, fresh basil and mint. I often add yogurt. Have fun with it! Think of your favorite juice combinations and buy those fruits.