For House Plants A plant setting in a sunny window receives less light than it would in a greenhouse or garden. A plant growing in a window gets light from only one side.
Plants show sensitivity to one sided light by leaning toward the light.
Light intensity varies with the season. Maximum light is available in summer, declines in autumn, and reaches a minimum in winter. During late winter and spring the amount of light increases toward the summer maximum. Watch plants for signs of light deficiency during the autumn or early winter. Deficient plants have pale spindly growth and may be gradually shifted to brighter windows.