When I first got these a few years ago, they were rare, and I had to order them online. Since then they have become common in Home Depots, etc. But if you really want the vivid color of the leaves, there are some tricks that I have discovered.
• Cut them back viciously. The beautiful leaf color is only from new growth, so chop the old canes down to the ground. I use a small curved saw.
• Cut off the blooms as soon as possible. The flowers look ratty pretty quickly, so that's not a problem. Remember that you are growing this plant for its gorgeous foliage, not flowers. The flowers are nice, and I leave them on for a while, but remember that flowers sap energy from the plant that could be used for foliage.
• Give them a lot of water. Find a boggy part of your yard. They love to have their *feet wet*. If you don't have an automatic watering system, I can't recommend growing cannas.
• Give them shade. Don't plant them out in full sun! A little bit of morning sun, like where these are, is OK.
• Feed them. All tropical plants are heavy feeders. Give them any brand you like, but feed them. A lot!
With care, cannas can be gorgeous in the Phoenix, Arizona area. Without care, they will grow, but will look starved, burnt, and ratty. And who wants that?