Life Span
Type
Origin
Types
Number of Varieties
Habitat
USDA Hardiness Zone
AHS Heat Zone
Sunset Zone
Habit
Symphytum officinale (common comfrey), Symphytum asperum (rough comfrey)
Cold Regions, stream banks
Southern Asia, India, China, Melanesia, Micronesia, Australia
Zingiber officinale, Alpinia purpurata
agricultural areas, Moist Soils, Warmer regions
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21