Zones 6–10 or 7–9, depending on the cultivar. Japanese spirea (Spiraea japonica) is a tough flowering shrub that never fails—one reason it’s often called a “gas station plant.” ...

For those seeking a tropical flowering shrub, growing ixora in the yard will certainly add color and impact. Ixora will grow happily outdoors in US hardiness zones 9 - 11, 'doing well in the heavy ...