The iris is a perennial herb that spreads by rhizomes. Irisis are planted from bulbs and can grow up to 3 feet tall. The flowers bloom in spring and are extremely showy. They range in color from red, purple and pink to yellow, white and blue. The iris is easy to grow and requires little maintenance. The iris grows best in USDA Hardiness Zones 3 through 8, which includes most of the United States.
Select a well-drained location that gets at least six hours of full sunshine a day. Plant your irises from August to September so they will be ready to bloom in the spring.
Prepare the soil before plant your bulbs. Use a tiller to work down 12 inches into the soil. Mix 2 to 3 inches of peat moss, bark or compost into the soil.
Dig a hole that is 4 inches deep and wide enough for the bulb to fit in. Bulbs should be planted about 8 to 16 inches apart to allow for spread.
Place the iris bulb into the hole and cover with native soil. The top part of the bulb should be just below the soil surface. Plant with the point of the bulb facing upward.
Water with 2-to-3 of water immediately after planting. Water with 1-to-2 inches of water in the spring during the blooming period. Do not water while the plants are dormant.