Extremely light-loving plants are relatively few in number. They are plants native to open areas where there is no shade of any kind, such as deserts, semi-deserts, steppes, salt marshes and exposed rocks. House plant varieties have, of course, already been adapted by Man. Therefore, cultivated forms of a naturally extremely photophilic species differ in their toleration of the lowered light intensity and shorter overall period of illumination found in the home.
Even the most light-loving plants defend themselves against the harmful effects of direct sunlight by a variety of methods. These include a variously fashionedepidermis, furling the leaf blade, and a covering of hairs. Some plants secrete essential oils that form a kind of protective coat to diffuse the light rays. Besides the intensity and property of light, the duration of daylight is also an important factor. The number of hours of daylight to which a species is adapted depends on the latitude of its natural habitat.
The best places for growing house plants that require lots of light are, windowboxes or windowsills facing west, southeast or southwest.