Mentha aquatica, aquatic mint, has a minty-fresh fragrance and lots of lilac to lavender-pink flowers that attract butterflies and butterflies. It tolerates full sun to partial shade and is hardy in zones 5 to 11. Use aquatic mint in the moist soil around your pond or grow it in water up to 2 inches deep.
Invite hummingbirds to your pond with the violet-lavender flowers of purple pickerel (Pontederia cordata). This fast-growing plant blooms from spring to fall in sun to part shade. Also known as pickerel rush or pickerel weed, it grows in water about a foot deep.