I'm really amazed at how they manage to push their way through those curved 'fishook' spines. I don' think I have ever got close to this plant without being snagged, and the hook is not easy to remove. That was how the plant came into my possession a couple of years ago at the cactus sale. I picked it up and it snagged my shirt. 'Take me home' it said. It has been a star performer though cold and heat.
It flowered in response to watering having been dry all summer.