Shishito pepper is small and finger-long, slender, and thin-walled. Although it turns from green to red upon ripening, it is usually harvested while green. The name refers to the fact that the tip of the chili pepper looks like the head of a lion , and in Japanese it is often abbreviated as shishitō.
About one out of every ten peppers is spicy. The occurrence of pungent fruit is induced by such factors as illumination, and other stress may predispose the peppers to turn spicy. The prefectural agricultural testing center at Kishigawa, Wakayama stated in 2005 that capsaicin forms more easily in hot and dry conditions in the summer, and even experts may not be able to distinguish relative hotness on the same plant.