How To Grow Japanese Roof Iris

The colony will slowly increase in size or you can speed the process along by dividing the plants in the fall.

How to grow japanese roof iris.

The rhizomes should be spaced 10 16 inches apart planted at 1 2 inches deep and will mature at soil level. Japanese iris require a minimum of 6 hours of full sun each day. By dividing rhizomes tubers corms or bulbs including offsets. Rich moist well drained and slightly acid.

Full sun preferred but some shade tolerated unlike many other iris soil. Japanese irises prefer a rich loose soil with ample organic matter. Japanese iris can be among the largest of the iris. They like moist well drained soil that is more on the acidic side.

How to grow japanese iris. Plant the rhizome with the roots spread out and the crown of the plant where the leaves and rhizome meet 2 to 3 inches deep. If a pond or water feature is not available growing japanese iris plants is best done in an area that remains damp and moist for best performance and easiest care of japanese iris. They are often planted on stream banks their natural habitat where the soil remains constantly moist.

In warmer climates shade in the afternoon is preferred to keep them from drying out. Like all irises it should be planted with the rhizomes just at the surface of the soil. Once planted and placed in the pond japanese iris care is minimal. One to two tablespoons complete fertilizer 10 10 10 before blooming.

This three year clump is ready for division. The soil ph should be slightly acid ideally between 5 5 to 6 5. Limit fertilization to plants with a well developed root system and only use plant food that is high in nitrogen. The japanese roof iris is unique amongst irises because it grows about as well in the shade as in the sun.

An addition of well aged manure and compost will help in water retention as well as adding nutrients. Water daily for a few weeks and then give them 2 inches of water a week until they are established. Japanese irises grow from a finger shaped fiber covered rhizome which grows in a more upright position than the creeping bearded iris rhizome. A tall growing iris reaching nearly 1m iris tectorum flowers in late spring to mid summer depending on climate and it does not like hot dry conditions.

They prefer a sunny to part shade location in rich well drained soil and benefit from the shelter of a wall with western or southern exposure and winter mulch.