Shrubs can offer additional energy savings by shading walls and air conditioners. A shaded air conditioning unit can offer 8% energy savings over one located in the sun. Shrubs serve many important landscape functions including screenings, hedges, accents, foundation plantings, and fragrance and color. Use green plants such as cherry and Viburnum suspensum for hedge work. Let flowering plants grow naturally so you can enjoy the blooms, which occur at the branch tips. 

Q. Can I save my crotons from this powdery growth? I've lost two already. 

A. Your crotons have lichens, which do not kill the plant. Check the trunk bases for string trimmer damage, which can girdle and kill the plants. Crotons can live for many years but have thin bark. 

Q. What is causing the leaves of my pittosporum to turn a spotted yellow and fade? 

A. Pittosporum belongs to a group of plants that prefers drier conditions than they normally receive in the irrigated landscape. Others in this group include citrus, carissa, Texas sage, geranuim, cacti, euphorbia, cassia, queen and areca palms, bird of paradise, royal poinciana, bulnesia, bougainvillea, ligustrum, and most legumes. This is by no means a comprehensive list. Change your watering habits immediately. Pittosporum is subject to root rot. Your leaves have angular leaf spot. Prune out dead branches. Clean up leaves under the plants. Keep mulch away from the base of the plants. Water only in the morning, no more than twice a week. Spray with copper fungicide following label directions and repeat treatment in ten days. 

Q. My juniper has bare spots and looks like it is dried out. What's wrong? 

A. Your variegated juniper has phomopsis; twig blight, which is common on junipers this far south. It occurs most often on plants grown in shady areas or where the shrubs receive a lot of water. Irrigate in the morning only. Keep the plant on the dry side, watering about once every four to five days if there is no rain. Spray twice with copper fungicide at weekly intervals. Juniper needs full sun and good air movement to minimize fungal problems.