The woolly butterfly bush (Buddleia marrubifolia) is an evergreen, round shrub that reaches 5 feet tall. This plant grows in the same conditions as the crown of thorns. When exposed to drought conditions, the leaves develop a silver color.
The best location is one that never floods, since both plants cannot tolerate wet roots. Place these plants in full sun and limited shade. Use sandy, gritty soil amended with peat moss or rotted compost.
These plants require little water. Let the soil dry out to the depth of 1 inch between watering sessions. Water the soil around the base of the plant. Do not water the leaves, since this promotes plant disease and leaf rot.