Purple and Blue Hawaiian Flowers Shown here are Hawaiian plants with conspicuous purple, blue, or violet flowers. Ageratum spp. – Ageratum Bougainvillea spp. – Bougainvillea Calathea burle-marxii – Ice Blue Calathea Commelina diffusa – Climbing Dayflower Desmodium intortum – Greenleaf Ticktrefoil Dichorisandra thyrsiflora – Blue Ginger 1 of 31>Last