Ginger is a rhizome (modified plant stem). True root vegetables are carb storage organs, either tap root or storage roots; tubers fit here also. http://www.ctahr.hawaii.edu/oc/freepubs/pdf/CFS-GIN-3A.pdf Down Under - The New Yorker. read more
Ginger is a stem vegetable because its used part is rhizome which is a modified subterranean stem. read more
Additionally, ginger root can be found in grocery stores in a vast array of forms -- from pickled, powdered and crushed to candied and dried. Because the portion of the ginger plant used is its root, the classification of ginger as a fruit or vegetable is not black and white. read more
Potato is a stem vegetable. Underground stem is modified into tubers. Sometimes we may notice that potatoes have partly or fully turned green. Green parts contain toxins and so should never be consumed. Potatoes are rich in starch and calorie content. The green sprouts arising from the potato too should not be eaten. read more