Artificial lighting

[Sara]

I have a 48" flourescent fixture with two 40 watt grow light bulbs. It worked really well for African Violets. What species of Orchids can do well under these lights? I don't have a lot of money to add or change anything to the fixture, just want to know what I can put under them. Thanks!

[mayres]

As far as the main genera of orchids that people grow you have TWO options. Phals and Paphs. You will want to grow them as close as possible to the bulbs - literally an inch or two if possible. Ideally bulbs should be replaced every 6 months for optimum light output or at least every year - even though they will look to the eye to be normal. You can put medium and high light level orchids under them and keep them alive for a long time, but they will not bloom and thrive. Good luck! mike

[jbigio]

I would go with either of the 2 that mike suggested. Also it would depend on the height from the shelve to the lights some Phals can get long spikes. I've gotten hooked on phap's of late and just got some big boys also.

[Fabolusus]

In addition to phals and paphs, you could also do some bulbophylums, depending on your humidity and water quality. I have a Bulb. medusae that is thriving under 2-23 watt cfls.

[Nancy]

Is there an easy way to tell how much light I have? I grow phalaenopsis on a window seat and a dendrobium, an oncidium, and three cattleyas on the window sill. I would like to supplement the light just on the sill. I can figure out how to do it, I just need an easy way to read what I have so I know where to start. Thanks.

[kmarch]

Originally Posted by Sara

I have a 48" flourescent fixture with two 40 watt grow light bulbs. It worked really well for African Violets. What species of Orchids can do well under these lights? I don't have a lot of money to add or change anything to the fixture...

If you want to save some money, don't use grow lights. Instead use one ordinary "cool" flourescent tube and one "warm" tube. They will cost about half (or less) than 2 grow lights and will produce almost exactly the same spectrum of light.

I grew under this sort of set up for about 5 years. I don't agree that you have to have the lights only an inch or 2 form the plants, in my set up the lights were on average 4-8 inches form the plants.

Under these conditions i successfully grew and bloomed:
Paphs - especially the Brachypetalum and mottle-leaf hybrids, a few mottle leaf species (P sukhakulii, P appletonianum, P wolterianum). Multi-florals need more light.

Coelogyne - especially C. fimbriata, C. ovalis, and C. speciosa. These all bloomed twice a year under these lights. Also you could grow other speciosa-type like C. xyerekes.

Phrags - I grew and flowered P. besseae, P. schlimii, and P xerophyticum. Many Phrags will require more light than this to bloom well so choose carefully and avoid the caudatum section species and hybrids.

And a variety of other orchids like: Masdevallias, Restrepias, Dendrobium moniliforme, Haraella retrocalla, Phal deliciosa, and a few others that I am forgetting.

Do some research before you buy and choose orchids that do well in medium-to-low light conditions.

Avoid most Cattleyas, Oncidiums, and all Vandas/Ascocentrum/Ascocenda.

If you have questions abour or have a difficult time finding info about a particular kind of orchid, let us know.

Happy growing!

[kmarch]

Originally Posted by Nancy

Is there an easy way to tell how much light I have? I grow phalaenopsis on a window seat ....

Where are you located (roughly) and what direction does your window face?

[kmarch]

Oh yeah, I forgot about Bulbos. Most of them do well in med-to-low light but you do have to have the humidity for them.

[mayres]

I do not doubt you CAN grow low light orchids at greater distances than a few inches (as I have and do do it with many of my own plants - in less than ideal conditions). However, the light intensity drops off dramatically with distance from the tubes - note a comment I made from a previous post:

Here are light intensities in footcandles noted from the University of Missouri Extension Service for fluorescent 40 watt tubes - depending upon lumen output of individual bulbs - your results may vary slightly - but will give you the general concept/intensity to expect:

2 tube fixture at 6" 500 footcandles, at 1 foot 260 footcandles, at 2 feet 110 footcandles, at four feet 40 footcandles

[Nancy]

I would say my window seat faces pretty much due north. This is the reason I want to supplement the light. The phalaenopsis appear to be doing fine in this light. I worry about the higher light demanding plants.

[mayres]

Due north windows is an EXCELLENT reason to add supplemental lighting! Have you gotten your phals to rebloom in the north window(s)? Someone I know here keeps her plant looking fairly healthy in a north but no reblooms - leaves are very dark green too (which generally indicates insufficient light). mike

[digitalgate]

hey i grow my phals, oncidium,mini cattleya, brassovola under FL. My
mini dendrodrium has bloom a few time under this arrangement.
Before you jump into buying plants. You must know , i am a orchid
hardcore. I spent a lot of money into the lighting, CO2 injection..
Your 80W is not enough to grow what I have. To do what I do
you need to do the follow
1)highly reflective aluminium reflector cost $15 , you need two so $15x2
2)four PL Osram Dulux constant each generate about 4500lux
each $15 so $15x4
3)electronic ballast dual tube connection each$10 you need two so $10x2
4) clip, wire,socket about $10
Total $120
plus you need to wire everything yourself.
you also need to change the PL FL tube every year.
Then your orchid will be happy.

[kot444]

Hi Digitalgate!
Can you clarify a little bit about ballast, Dulux need magnetic ballast, can it be obtained separately, where?

[digitalgate]

I am using ebiru electronic ballast 54W (on a 55watt PL) it work fine. I guess any e-ballast work just fine(proper wattage) . Dont use those that need to use
a starter , osram tube did specify that.
I stay in Asia. I remember when i was in Minneapolis
i had a hard time looking for electronic ballast. May be you can try google.
try google for eballast. that might help. But if you intend to go for my kind of
setup. I suggest trying the lastest in FL technology - T5HO. It rival
HID output without the heat.
I guess heat might not be a problem for you up north. it is also found on the osram website.
sorry I dont know any shop or site that sell eballast and T5 HO tube.
I just went to my local hardware shop for it.

[digitalgate]

e ballast come separately with the PL tube

[kmarch]

Or......

You could go to Lowe's and buy 2 2-tube shoplights (about $15 each) and 4 flourescent tubes (2 cool, 2 warm, about $4 each).

Total: about $46.

Mottle-leaf Paphs can grow well in the same light s your Phal.

[digitalgate]

ordinary FL is fine with Phal but you will be changing light tube very frequently.
Like the old saying , you get what you paid for.

[Nancy]

I added supplemental light to the window this p[ast weekend. I'm going to have to wait to see if there are any results. I added two 100 watt daylight bulbs in reflectors. My collection is small so hopefully this is enough light added to the natural light to keep the orchids happy. I have one shining directly down on the oncidium Sharry Baby, which is completing a new growth. Please let me know what you think.

[mayres]

The first winter I had orchids (about 3 years ago) I only had 6-8 plants and placed a 100 watt tungsten bulb w/reflector over them as you describe. It worked OK for a few plants, but was poor use of resources. A much better choice would be a CFL bulb in the same reflector - you should be able to find a compact fluorescent bulb at a place like Home Depot or Lowes that is the equivalent of a 150 or even 200 W tungsten bulb - that uses less electricity and provides more light for your orchids. They do not waste energy producing heat like conventional bulbs. Because they are not hot you can get them a lot closer to your plants too - which is good - generally the closer the better with non-commercial lighting.

[Nancy]

The two bulbs are flourescent. My husband is obsesively cost conscious about lightbulbs.