Bok choy is best left to harvest as a whole head. Wait to for it to be nice size and remove the entire boy boy for your next stir fry. All other Leafy greens are easy to harvest. Go out with a big bowl in the garden and harvest the outer leaves of our leafy greens (kale, swiss chard, lettuce, tatsoi, roquette). Harvest your salad daily and enjoy these tasty greens.