South and east-facing windows work best for orchids. West_windows can be too hot in the afternoon and north-facing ones are usually too dark. A sheer curtain will cast light shade. Too much direct light causes leaves to sunburn - so it may be necessary to re-position plants as the seasons change. Move plants away from or toward the window to manipulate the amount of light. Make sure the leaves are not touching the glass. In winter in a cold climate, leaves touching the windowpane may freeze.

Leaf color indicates if the amount of light is adequate. The lush, rich, dark green of most houseplants is not desirable in orchid leaves. A grassy green color (light or medium green with yellowish tones) means the plant is receiving sufficient light to bloom.