Texas FFA Nursery Landscape Practice Exam

Which plant hardiness zone is colder than Zone 6?

1. Zone 7

2. Zone 10

3. Zone 3

4. Zone 8

The correct answer is: Zone 3

The coldest plant hardiness zones are ranked by their minimum average winter temperatures, which allows horticulturists to determine what plants can thrive in given regions. Zone 6 has a minimum average winter temperature range of 0°F to -10°F. Zone 3, which is colder than Zone 6, has a minimum average temperature that can drop as low as -40°F to -30°F. This significant difference in temperature explains why specific plants suited to warmer zones may struggle in places classified as Zone 3. In contrast, Zones 7 and 8 are both warmer than Zone 6, with Zone 7 ranging from 0°F to 10°F and Zone 8 ranging from 10°F to 20°F. Zone 10 is even warmer, with a minimum range of 30°F to 40°F. Understanding these temperature ranges is critical for selecting appropriate plants for landscaping and gardening projects based on the climate of the specific location.