Marsilea mutica

Despite its common name and appearance of a 4 leaf clover or shamrock, the Marsileas are actually a fern that reproduces from spores. The Four Leaf Clover is easy to grow and its attractive green leaves close up at night which sort of resembles butterflies resting with closed wings. The Four Leaf Clover differs from our other Marsileas in that the leaves float on the water's surface. Hardy in zones 5-11.