Hardiness ratings: USDA zone 5 - 8~10
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- GRIN. Taxonomical details, with common names, distribution, and synonyms.
- The Plant List. Taxonomical lookup
Links for Viola jooi
- All Things Plants - Community-assembled plant profile (2 photos)
- Alpine Garden Society - Ulster - Plant of the month profile (3 photos)
- Dave's Garden PlantFiles - Profile page with horticultural basics, and member-contributed photos and comments. (zone 5-8) (3 photos)
- NARGS Image Gallery - Photograph(s) contributed by North American Rock Garden Society members. (1 photo)
- Rob's Plants - Plant profile with basic horticultural information and often personal observations. Also seed germination records. (zone 5-10) (3 photos)