Amplissimus Rose of Sharon produces 2-3" wide, double, purplish-red flowers throughout much of summer on this easy to grow vigorous shrub, which is very tolerant of heat and most growing conditions. Althea or Rose of Sharon is a hardy Hibiscus that naturally develops into a multi-stemmed, vase-shaped deciduous shrub that can be trained into a tree form if desired. Provide an average moist to moderately moist, fertile soil and full sun for optimum growth and flowering. Caterpillar host: Gray hairstreak. Item# 10338.