Roof Iris

The silken flowers grow on upright stems up to 45cm (though 30cm seems average) and proffer two to four flowers (Oct-Nov). Each bloom is an impressive 10cm across.

The fanned leaves are quite a handsome feature. The sword shaped leaves are light green and grow 20-60cm tall. They will form clumps at a steady rate in ideal conditions, and should be divided every three years or so. Thick, creeping rhizomes that grow gradually into clumps. In more mild climates they may remain evergreen but they generally go dormant late autumn.

Iris tectorum will grow in sun or dappled shade. Water to establish and keep moist during active growth. The more sun they are in the more water they will need. They thrive in humus rich soils and prosper when they have a decent amount of fertiliser. Native to the edges of woodlands and open fields of China, Korea and Burma.

Iris tectorum is commonly known as the Roof Iris as in parts of country Japan they have grown it on the ridges of their thatched rooves. Why? We couldn’t find a definitive answer but there are a few theories; the first is that the roots are useful for binding the thatch and clay. The second is that during Japan’s famine all grounds were to be used only for food cultivation, so flowers were outlawed. However the roots of this particular flower were used to make a white face powder for women so rather than not be able to make the powder they moved the flowers from the soil to the thatched rooves and the Iris grew well amid the clay. The third reason is perhaps because they were to ward off evil spirits.