Iris ensata Aichi-no-Kagayaki - Japanese Water Iris

They thrive in damp and marshy soil, free from limestone. They also tolerate moist soil, as long as it doesn't become waterlogged, provided it doesn't dry out in summer. However, they prefer relatively dry soil in winter. At Le Clos, we have planted them near an artificial stream, keeping the water level high during the summer. In winter, we let the water level drop by about 15cm (6in), so that the stumps are above the water, just like in nature where river levels decrease in winter and rise again in spring with the melting snow. Their cold resistance is excellent, up to about -12°C (10.4°F). It is even greater if the soil is dry.