The gardener must at times give plants protection against too intense light and against excessively high temperatures.
Damage from intense light is most likely to occur when naturally shade loving plants are exposed to direct, strong sunshine; when sun loving plants, comparatively soft and tender from being grown in a greenhouse or cold frame, are transferred outdoors; and after plants are transplanted. The trunks of trees that have been growing closely together in woodland or nursery may be damaged by sunscald on their south facing sides following their transference to sunnier locations; by heavy pruning, branches previously shaded by foliage may be exposed to sunshine sufficiently strong to sunscald them. Damage by sun occurs not only in summer; in winter, when the ground is frozen, evergreens, especially, are likely to suffer from this.
The provision of shade is the obvious method of avoiding damage by light that is too intense. Shade needing plants should be grown in naturally shaded areas, such as woodland, under solitary trees or groups of trees, and areas shaded by high walls or buildings or in locations artificially shaded by lath houses, lath or burlap screens or other appropriate means.
The trunks of trees may, with advantage, be wrapped in burlap or in special tree wrapping
paper for a season or two following transplanting. When annuals, vegetables, young biennials and perennials are set out in hot sunny weather they should be shaded for a few days following the transplanting operation.
Not a great deal can be done to lower summer temperatures; but in every garden some locations are noticeably warmer than others. At the base of a south facing wall, for example, the temperature is very noticeably higher than at theRead more on backyardgardener.com