Add the apple juice to a high-speed blender first.
Add the kale, strawberries, purple grapes, and frozen banana.
Add the moringa, Zen Basil Seeds, and ground flaxseed, if using.
Blend on high for 45–60 seconds, or until completely smooth and pourable.
If the smoothie is thicker than desired, add a splash of additional apple juice or filtered water and blend again.
Pour into a glass and serve immediately.