Product Review

Zones 4 - 11. This aquatic perennial's tuberous roots colonize the soil at the bottom of earth-bottom ponds, or the soil in containers fully submerged in lined ponds. The stems of the leaves can reach the surface of water that's nearly two feet deep-and then continue upward, above the water, a few inches or even a foot farther. The roots don't tolerate frost but the tubers and roots are hardy anywhere the water above the soil is deep enough that the pond's surface-ice doesn't freeze all the way down to the soil, and yet is not so deep that their leaves can't reach at least a bit above the water's surface to get the full sun they need to grow and flower: From the frost-free tropics of Zone 11, then, all the way down to the seriously-Wintered Zone 4 of Northern Vermont and Canada. Few plants, aquatic or terrestrial, have such a world-wide versatility.