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Growing Perennials As Annuals
Disregarding Mother Nature's intentions
Sometimes the plants don't give you any choice. Like kids approaching adulthood, they find more nourishment in the big bad world than in their cozy homes. Leave them confined too long and they start to lose their spark. On the other hand, some plants thrive in confinement, but may be too tender to withstand adverse weather conditions. Unless you have room to move them indoors, the temperate season is the only time you have to enjoy them.
Other plants may grow too fast and too big and will burst their bounds and escape unless we quickly put an end to their antics. You shouldn't be limited to growing annuals in containers out of fear of breaking the rules of perennials. Be brave, experiment with whatever you can find. If you want to keep a plant around, keep it. Enjoy the process - it's your garden, you can do what you want.