Orchid 101

[Maleficent2]

inspired by the thread on orchids. I thought I would post a how to grow thread....

TOO LITTLE LIGHT - -

How do I know if I am not getting enough light?

If your orchid is showing any of these signs, chances are it is not getting enough light.

Dark green leaves with no luster to them. The roots system is fine.
Each new growth is smaller than the last growth.
Your orchid is floppy and very weak looking.
It has not bloomed or it has very few blooms.

How can I increase my light?

You need to move your orchids into a better light source, a different window, open the curtains, remove objects that maybe shading the window such as a tree or awning.
Be very careful when introducing you orchid (or any plant, for that matter) to more light because a plant that has been in poor light for any length of time will have very delicate leaves that can burn easily. Move your plant to a higher light level gradually over several days. If you notice the plant leaves burning (they will turn brown and be very dry), move the plant further away from the light source or provide some shading for a week or two until the plant gets used to the increased light.

If you are growing your orchids under electric lights: ( I don't use electric lights but some do)

Reduce the distance between the light and the plant.
NOTE: If you are using incandescent lamps, be careful not to place the plants too close to the hot light.
Move the plant toward the center of the light.
You should operate your lights 14 to 16 hours a day.
Make sure the bulbs are not over a year old, older bulbs tend to give out less light.
Use a special "grow light" in your fixture.

 

[Maleficent2]

How do I know if I am getting to much light?

There are several ways you can tell if your orchid is getting too much light:

The leaves are showing burn spots. The spots can be yellow or brown dry patches on the leaves. They could also be rough and slightly raised.
The leaves feel hot to the touch. Leaves should be cool to the touch.
The leaves start turning black and dropping off. A plant exposed to too much sunlight will eventually die.
The plant's growth is stunted and the leaves start to turn yellow.
On some orchids, the color is bleached out of the leaves.

How can I reduce the amount of light?

This is easier to control than not enough light.

Move the plant away from the hot sun. Remember that the sun coming thru a window and maybe intensified by the glass.
Afternoon sun is also much "hotter" (brighter) than the morning sun, so move the plant to a East-facing window.
Place shear curtains in front of the windows.
Provide shade if growing out doors. A plant that may be fine in the spring but could get burned as the sun moves higher in the sky toward summer.

If you are growing under lights, you usually don't run into this problem unless you leave your lights on all the time or the lights are too close to the plants.

 

[Maleficent2]

Light is measured in a unit called a footcandle (fc). A footcandle is equivalent amount of light that is produced by a candle at the distance of one foot. To give you an idea of light levels, on a clear sunny summer day at noon, the light in the sun would be over 10,000 fc. At the same time of day on a overcast winter day, the light level may be less than 500 fc.





Phalaenopsis 1000-1500 fc Never exposed to direct sun light.
Paphiopedilums 1000-3000 fc Expose to only early morning sun.
Miltonia 1000-3000 fc Keep in diffused light.
Odontoglossums 1500-2000 fc Expose only to morning or evening sun.
Cattleyas 1500-3500 fc Give plenty of light without burning their leaves.
Vanda 1500-4000 fc They like strong light, full morning sun.
Oncidiums 1500-4000 fc Same as above.
Dendrobiums 1500-4000 fc Same as above.
Cymbidiums 7000-8000 fc Give as much light as possible without burning the leaves. Provide lower light (2000-3000 fc) when flower spike appears.

NOTE: as with most plants there are species in these genera that may require different light levels.

 

[DebºoºS]

Thank you very interesting information. Encouraging for me because if I can get a dendrobium to bloom then maybe I can try another.
Uh oh, I may just have to start orchid shopping.

What about humidity? Do some require more than others? I have mine next to the kitchen sink so it gets some moisture. Do you mist yours?

 

[grlpwrd]

Yes, thank you for such great info. After reading about orchids here I think I'm going to give it a try. I am from Hawaii and I grew up on the Big Island where orchids are prolific yet I didn't have a clue until now. Thanks again.

 

[Maleficent2]

no I never mist...Deb I think you can do it just pick a healthy plant and go for it!!!!


more how to to come....

Mal

 

[Maleficent2]

I don't worry about this maybe because I live in the south and it humid here I don't need to. I dunno. I water my plants one by one in the kitchen sink and give them a bath everytime I water so maybe that helps also.

Orchids lose water through pores (stomata) found on their leaves. The drier the air, the faster the orchid will loose its moisture. Keeping the humidity high reduces the speed of water loss (dehydration). Orchids prefer a location where there is a range of humidity between 40% and 70%.

You should not try and keep your humidity at the same percentage all the time. A fluctuation of humidity is desirable and gives the plants a chance to "dry out." A 40% drop during the day for short periods can be beneficial to your orchids.

CONTROLLING HUMIDITY - -

Raising humidity

In a greenhouse, you can wet down the walks and floors to increase the humidity.

In your home, a humidity tray works very well. A humidity tray is any kind of shallow container that will hold water. Just add some pebbles and water. Place the orchid above the tray making sure the pot does not touch the gravel. You can also increase the water evaporation from the tray by adding a heating cable (sold for germination of seeds) under the gravel.( I don't use these but if your house is dry it is an option.)

Group your plants together but allow space so that it there air movement around each plant. The grouped plants will assist each other in forming their own beneficial micro-climate cause by their own evaporation.

Humidifiers before buying one, if you do not already own one, test your air with a hygrometer to see if you really need one.

If possible, grow your orchids in the kitchen by the sink, in the bathroom, the wash room, or anywhere hot water is used. The evaporation of the water adds moisture to the air. Although I grow mine all over the house.

Make sure your furnace and air conditioning units are not blowing hot or cold air directly on your orchids

Misting does little for raising the humidity. The water in the air quickly evaporates. If you mist be sure and do it early in the day so that any moisture on the plants leaves will be dry by evening.

Lowering Humidity


Excessive humidity is rarely a problem for orchids grown in the home. High humidity is usually more prominent in a greenhouse because of the greenhouse's sealed environment. This is especially true if you live in an area where the climate is damp or in and area where winters are dull and cloudy most of the time.

A sign of excessive humidity or damp stagnant air is the formation of brown water spots on the leaves, small pink or brown spots on the blooms, and the flower sheaths turning black (in extreme cases).

To correct the problem, you need to increase the air movement with fans to dry out the area. Vent the area to the outside if the humidity outside is lower than inside. Be careful not to introduce hot or cold drafts on your orchids while venting. Decrease watering if possible and DON'T mist.

 

[Maleficent2]

Orchids do not like stagnant air. In their natural habitat, most orchids grow high up in trees where the breezes are always blowing. Wind cools the leaves when it is hot, and helps dry excess moisture that may have accumulated on the plant. Wind also helps distribute warm and cold air so harmful air pockets don't form.

At home in spring, summmer and fall you can open a window. Although some people like to summer their orchids outdoors be careful of sunburn if you do this.

Ceiling fans work well.

You should never smoke around your orchids. If you do smoke, be sure you wash your hands before handling your orchids to prevent spreading a deadly virus called Tobacco Mosaic Virus to your beautiful orchids.

Viruses are the most worrisome threat to cultivated orchids. The two most common are cymbidium mosaic virus and tobacco mosaic virus. The effects are overall yellowing (chlorosis), death of tissue, and restricted or stunted growth. There may also be streaking in the floral parts. Ringspot on the leaves is a sign of tobacco mosaic virus. Be aware that almost any of these symptoms can be traced to problems of nutrition, chemical imbalance, excessive salts in the water supply, insects, or damage from sprays. Be finicky about cleaning and grooming your orchids and the area in which they grow. It’s the best defense against virus and most other orchid pestilence.

Keep your orcids and your apples away from each other, A basket of apples can generate enough ethylene gas to cause your flowers to wilt and turn black.

 

[Snowwark]

This is wonderful, Mal, thank you very much!!

Beautiful pic!

 

[Maleficent2]

will do that soon. Just wanted to say if this makes them sound difficult they really aren't.

I hardly give mine a second thought and they do very well...maybe that is why

Mal

 

[DebºoºS]

Thank you so much for posting these tips. You're giving me confidence