Unless one visits a greenhouse or someone with a lot of indoor plants, cacti aren't common in Iowa. But, on a recent trip to an indoor growing facility, I spotted all sorts of cacti with blooms -- what a treat! And, after reading about these spiny wonders, I now understand that cacti are considered flowering plants capable of blooming when mature; however, whether or not a cactus actually flowers depends on its age and growing conditions. For example, the tall, columnar Saguaro cactus (found in the Desert Southwest) may first flower after 40-55 years of growth.
Enjoy a close-up view but be careful when you touch!