 Flowers blue. Plant without underground runners. Leaves usually with a heart shaped base. (Viola canina)
by Rogier van Vugt
|  Flowers small (Around one cm), white or yellow rarely faint blue in the upper petals. (Viola arvensis)
by Rogier van Vugt
|  Viola
by Douglas Houck
|  Anual or short lived perrenial plant. Flowers bicoloured with purple. A plant of arable and disturbed soil (Viola tricolor)
by Rogier van Vugt
|  Flowers fragrant, dark bluish lilac. (sometimes white). Forms colonies by means of thin runners. (Viola odorata)
by Rogier van Vugt
|