Whether there is already enough shade elsewhere in the garden or there is not enough space for more trees, planting more shade trees is not always an option.

Finding plants that like heat is as easy as finding plants that like full sun exposure. The difficulty is finding plants that tolerate both in extremes. Heat enhances exposure like exposure enhances heat. Glare from reflective surfaces enhances both. During very warm weather, even the most resilient of plants can be damaged in areas of the garden that are near pavement, walls, fences, windows or even parked cars--anything that creates glare. Roofing material can create glare that can be just as damaging to trees that are still too small to provide their own shade. Light colors are more reflective than dark colors.

Too much exposure to sunlight, heat and glare can cause wilting, foliar scorch or sunscald (of the cambium). Wilting can usually be corrected by a quick and generous watering (if the soil is dry) and spraying the affected foliage with water. Plants that are susceptible to fungal diseases should not be sprayed with water frequently or so late in the day that the foliage will remain wet overnight. Scorch cannot be corrected because it usually becomes apparent the day after the damage is incurred.

Sunscald only affects bare stems or trunks. This is why the trunks of so many young orchard trees that occupied the Santa Clara Valley so many years ago were painted white. Although white paint effectively reflects sunlight, it would be rather unsightly in the garden. Trunks of young trees that are sensitive to sunscald, such as flowering cherries and maples (shade tree types), can be shaded by wide stakes attached to the south-southwest side of the trunks. Unless these stakes are also needed for support, they do not need to be attached too firmly. As the canopies grow large enough to shade the trunks, the shading stakes can be removed.

Small plants are more susceptible to damage from over-exposure. As plants grow and produce more foliage, they absorb more ambient glare. Larger plants may likewise absorb glare that might otherwise damage nearby smaller plants, even if the smaller plants are completely exposed. Many plants are more sensitive when first planted also because they are more exposed in the garden than they were in the nursery.

Plants that are resilient to heat and sun exposure are, of course, more practical for the most harshly exposed areas than plants that will need protection. Fig, olive and various melaleucas and eucalypti are some of the toughest trees. Pomegranate, bottlebrush, oleander, photinia and various pittosporums and junipers are excellent shrubs or small trees. Red trumpet vine and bougainvillea are vines that are comparably resilient.

A few plants that are too aggressive or too awkward for more cultivated areas of the garden are just fine for areas that are so exposed that not much else will grow there. The voraciousness of some types of bamboo is precisely what makes them ideal for inhospitable situations. Most palms can be damaged by extreme exposure when young, but quickly outgrow this sensitivity. Whether shrubby or tree-like, yuccas are happy in any location.

Flower of the Week:
Fringe flower

Contemporary cultivars of fringe flower, Loropetalum chinense, with purple foliage and pink or purplish pink flowers have recently become more popular than the traditional fringe flower, with 1 1/2- inch-long soft green leaves and pale white flowers. Clusters of five or so flowers bloom most profusely in spring, and individual flowers bloom throughout the year. Each flower has four narrow, twisted petals that are about an inch long.

Mature plants are about 3 feet tall, but may get considerably larger. Unless pruned, the limber branches arch softly outward. They like partial shade, rich soil and frequent watering.

Horticulturist Tony Tomeo can be contacted at 408.358.2574 or at LGHORTICULTURE@aol.com.