How to Grow Iris

The most familiar member of this group is the bearded iris (Iris x germanica) that blooms in late spring. The large, handsome flowers are composed of three ruffled petals called standards, which stand upright, and three petals called falls, which hang down. The range of color is extraordinary every color except bright red; sometimes the falls and standards are colored differently. The gray green sword like leaves is easy to hide with other plants after the flowers have bloomed so they will not take up visual space. For this reason you need to use iris in the border, although other gardeners prefer to mass them by themselves, which creates a lovely effect. Heights range from to four feet. 

The two other types well worth exploring are Siberian Iris (I. sibirica) and Japanese iris (I. ensata, also called I. kaempferi). Siberian iris quickly forms large clumps of slender upright leaves. The flowers are more dainty than those of bearded iris; shades include blues, purples, rose and white, some with exquisitely veined markings. Japanese iris is same; however the flowers are much larger and bloom a bit later. 

Well, if you want to grow iris, then roots of bearded iris are fat rhizomes that are prone to rot and to infestation by root maggots. I fight both problems by dipping the roots in a ten to one chlorine solution whenever dig them up to divide them, but the best prevention for rot and maggots is to plant the roots so that the tops are visible. You can plant them on a soil mound if drainage is less than perfect. They like fairly rich, alkaline soil and are generally planted in later summer. 

The roots of Japanese and Siberian iris are long and stringy. The plants like moist, slightly acid soil that is rich in humus. Divide Japanese iris every few years. Siberian clumps can be left undisturbed, but for purposes of propagation, divide with a sharp spade or digging fork. The roots of old clumps become densely matted together but can be pried apart with two digging forks worked back to back.