A sepal is one of the small, leaf-like parts that protect a flower bud before it opens. If you look at a rosebud before it blooms, those green, leaf-looking pieces wrapped around the outside are sepals. They form a protective layer around the delicate petals inside, keeping them safe from insects, weather, and damage while the flower develops.

Once the flower opens, the sepals usually stay attached at the base of the bloom. Sometimes they're green and hardly noticeable, like on a daisy. Other times they're colorful and showy, like on a fuchsia, where the bright red sepals look almost as beautiful as the petals themselves. On some flowers, like lilies, the sepals and petals look so similar you can barely tell them apart.

Together, all the sepals on a flower form the calyx, which sounds fancy but just means the outer protective cup. Next time you pick a flower or look at one closely, check the base: those sepals are nature's way of keeping something beautiful safe until it's ready to show itself to the world.