Yes, it is February....still mid-winter for us here in the Chicago area.  Thus it may seem a bit strange to be bringing up the subject of sunburn.  However, it is important to remember that your orchids can get scorched this time of year. 

 

Starting in mid-February the sun's rays begin to gain strength.  At our latitude, we welcome the increased daylight hours and the higher arc of the golden globe as is warms the greenhouse (despite sub-zero temps outside!)  The cold weather makes it easy to forget that the same rays that warm us and provide plant growth can also burn the leaves of orchids that sit naked in an unfiltered windowsill or a "shade-less" greenhouse. 

                               Sunburn Spot!

If you are growing in a south or west-facing window, you may want to begin to shade your orchids this time of year, especially on sunny days.  Partially closed blinds or a sheer curtain work well.  If you have a greenhouse, your shading compound (or cloth) should be in place by the end of February or early March.  If this isn't possible, you might have to move your plants out of the direct, mid-day rays of the sun.  You can also minimize the chance of sun damage by misting the plants lightly on sunny days. 

 

Brown burn spots will occur even on higher-light plants like Vandas and Cattleyas if the direct hot rays hit the leaves for extended periods of time.  So make sure to protect your plants as you enjoy the warmth and brightness of the sun! 

 

Happy Growing,

Liese