Good fortune awaits the gardener who grows Crown of Thorns Serendipity. The large, 1-2 flowers have deep pink inner petals with light, cream-colored petal edges. It creates a magnificent floral show during the spring and summer blooming season. Euphorbias are indestructible houseplants that thrive on neglect. Be sure to let the soil dry out between waterings. This easy-care plant will thrive on a sunny windowsill or grow it outside during the warm summer months.