- Protect your plants from strong sunlight and heat
- Use appropriate shade cloth
- Water and mist several times a day
Low light for orchids is about 1,000 to 1,500 foot-candles. This is the amount of light they would get naturally in the lowest levels of a heavily canopied tropical forest.
Orchids such as Paphiopedilum and Phalaenopsis thrive in low light and will burn and fail to flower in higher light levels. In a greenhouse or shade house, use 70% to 80% shade cloth
Medium light orchids such as Cattleyas need about 1,500 to 3,000 foot-candles of light.
This is the amount of light an orchid would get growing midway in the canopy of a tree where the branches begin to open up a bit. In the greenhouse or shade house, use 50% shade cloth.
High light orchids tolerate light levels of 3,000 to 4,500 foot candles of light. This is the amount of light that reaches the dappled shade of the uppermost canopy of a tree.
Some high light loving orchids are Vandas and some Cattleyas. In the greenhouse or shade house, use 20% shade cloth.
Very few orchids like full sun all day
Measuring Light Levels
Measuring light levels for orchids takes some experience, but there are some ways to help. A light meter is the best way, but light meters can be expensive.
An alternative is to use the shadow cast by your hand on a sheet of white paper 1 foot away.
Full sun at noon in the summer is around 10,000 foot-candles, and your hand will cast a clearly defined dark shadow, under low light conditions, the shadow of your hand will be blurry, and it may be difficult to make out a distinct shape.
Under medium light, you will have a clearly defined shadow that is slightly blurry. In high light conditions, the shadow will be dark and crisp, but not as defined as under full sun.
What is shade cloth and do I need it?
Shade cloth is a commercially available material for placing over your greenhouse or shade house to cool it in the summer and provide a lower amount of light.
It is usually made of loosely woven polyester and can be found in varying densities or degrees of shade from approximately 5% to 95%.
If you live in a humid area, misting or fogging may not be enough to cool your greenhouse or shade house in the hot, humid summer months. When all else fails, you can create your own shade by using shade cloth.