Which statement about plant hardiness zones is true?

• A. Zone 3 plants cannot survive in Zone 5
• B. Zone 5 plants cannot survive in Zone 3
• C. Zone 5 plants thrive in Zone 3
• D. Zone 3 plants thrive in Zone 7

Answer: (B)

Plant hardiness zones show the coldest winter temperatures a plant can endure. Higher numbers are warmer, meaning a plant rated for a given zone can survive winters typical of that zone or milder, but not much colder ones.

A plant that is hardy to Zone 5 can survive winter temperatures around -20 to -10°F. Zone 3 experiences far colder winters, so those colder conditions exceed the plant’s tolerance and it would not survive there. That’s why the statement about Zone 5 plants not surviving Zone 3 is true.

In contrast, a Zone 3 plant can typically survive in Zone 5 because winters are milder there, and a Zone 5 plant would not survive a Zone 3 winter. The idea that Zone 3 plants would thrive in Zone 7 is not guaranteed, since thriving depends on more than just winter tolerance.