September 6, 2014
When to plant irises in the Phoenix, Arizona area - September
The best place to plant them I've found is in a sunny area that collects a lot of water. This area along the edge of the yard collected so much water that it started to sink, so I put a big piece of flagstone there recently, and made a mental note to plant irises there. In fact, many of the iris plants are still growing there from last season, as you can see. The new ones are just bulbs, you really won't see them until they start to grow. In a month, the leaves will be about two feet tall, and much wider.
In spite of their size, I have learned to keep irises as foreground plants. That's because their blooms don't last, and need to be trimmed off constantly during the blooming season. If they're way back in an inaccessible area, the temptation is to leave them alone. So keep them front and center and easy to trim the spent blooms right away. It's those ratty spent blooms that gives the iris a bad name.
Plant an iris bulb shallowly. Technically, it's not a bulb at all, it's a rhizome, and that means that it's just a giant blooming grass. Be sure to have plenty of soft potting soil for the roots to grow into (they'll try to grow in Arizona soil, but they'll look ratty). Then give them as much water and fertilizer that you want.
Personally, I love the lush blue-green foliage of an iris plant. The blooms in the spring are just the finishing touch!
Posted by Brad Hall