What do I do with early spring planted cool-season annuals when summer arrives?

FAQ
Question: 

What do I do with early spring planted cool-season annuals when summer arrives?

Answer: 

Cool-season annuals are annual plants that prefer cool temperatures, growing best in spring or fall. Many are tolerant of a light frost often surviving down to 28°F or sometimes even 25°F with little damage to flowers or leaves.

Since nearly all cool-season annuals do not grow well in warm temperatures, especially those that exceed 80 to 85°F, they can be replaced with summer annuals once the danger of frost passes in early to mid-May for much of Iowa.