The Watermelon Zkittlez strain yield is more impressive than most. Especially at the hands of experienced growers. That said, the plant is easy to grow regardless of skill level. Even a basic understanding of cultivation will go a long way. Watermelon Zkittlez plants grow to a medium height with large colas and dense, heart-shaped buds. Yield You Can Expect From Watermelon Zkittlez Watermelon Skittlez can be grown indoors and outdoors but thrives outdoors. Outdoors you can expect around 5 ounces per plant. Indoors you can expect 0.5 ounces per square foot. Researching which strains will give you the best yield can be important.