Dutch irises (Iris x hollandica) grow from bulbs on 2-foot tall stems. Unlike most irises, they have grassy foliage. The falls, or lower petals, of the flowers are oval or circular, and the upper petals, or standards, stand straight. Dutch irises make wonderful cut flowers.
Find a sunny spot for your irises where they'll get direct sunlight at least six hours a day.
Make sure the place has well-drained soil. To check this, soak the ground completely and time how long it takes the water to drain away. If puddles are standing five hours after you water, you should pick a different spot or amend the soil with compost.
Dig up the flower bed thoroughly, to a depth of 4 or 5 inches. If you need to amend the soil, mix in enough compost to bring the level of the soil up 2 to 3 inches higher than it originally was.
Dig individual holes for each Dutch iris bulb, 4 inches deep and 3 inches apart.
Put each bulb in its hole, pointed side up.
Cover each bulb with 4 inches of soil.
Water the bulbs until the soil is soaked.
Check on your irises every three or four days to see if they need more water. Stick your fingers in the soil to see if it's still moist. If it's drying out, water the bulbs until the ground is soaked.