The yellow flag iris has brilliant yellow blooms and grows to a height which often exceeds three feet. The foliage of this iris has narrow leaves that are a unique shade of blue green. Different varieties of irises have individual location, planting, and care requirements. This should be taken into consideration when choosing a location for planting. Unless the variety chosen thrives in moist areas, a location that drains well should be chosen so the roots do not rot.
Perennial irises grow from a root which is known as a rhizome.
When planting a rhizome, begin by digging a hole that is approximately six inches deep. Soil should be mounded in the bottom of the hole so when the root is planted it will be just below the surface of the ground. After planting and tamping down the soil, the rhizome should be thoroughly watered. Be sure that any additional irises planted are at least twelve inches apart. One of the most common problems with irises is spotting of the leaves.