How Shade Plants are Different
Plants use the energy from sunlight to produce the food they need in order to grow. In this sense, all plants need some light to survive. But don’t confuse light with direct sunlight; many plants can exist on relatively small amounts of reflected light.
As light falls on the plant’s leaves, the chlorophyll (green pigment) inside the leaf uses the energy contained in the light to convert water and carbon dioxide into oxygen and sugar, which, in turn, power the plant’s growth process. The plant receives most of its water from beneath the surface of the soil; the carbon dioxide is taken from the air surrounding the plant and processed through the pores of the leaves. This miraculous process is known photosynthesis, and to this day it is not completely understood. The accompanying illustration shows how this complex system works.
Some plants are adapted to growing in shady locations. These “shade lovers” usually have more chlorophyll than plants adapted to the sun. Their leaves are more sensitive to light and better able to make use of a small amount. But the price they pay for this sensitivity is that they are not tough enough to tolerate direct sun for long. The brightness of direct sunlight bleaches their leaves to a yellow or gray color by destroying chlorophyll.
Then these bleached leaves are not able to protect themselves from the heat of the sun. On warm days, they overheat and die, either by scorching at the edges, or by developing burned spots on the surfaces that face the sun.
Even a cursory understanding of how a plant works can greatly increase your competence as a gardener—especially when it comes to gardening in the shade.
