Lighting suggestions

[PHRAG]

I am at a cultural crossroads. For a while now I have been growing in my greenhouse using two 150w spots. I need a lighting upgrade to match how much my orchid collection has grown. I found a place where I can buy clamp-lamps for $8 each. But it would take a ton of clamp lamps to light the entire greenhouse.

I have considered stepping up to flourescent tubes in a shoplight setup, but those would be hard to hang in the greenhouse. And don't the plants have to sit within 6 inches of the bulbs? Definitely hard with the variable height my plants sit at now.

HID would probably melt the leaves off the plants and the greenhouse itself.

So what do you recommend? I measured my light output last night in lux and converted to footcandles, and I need more light. I know that is not exactly accurate measurement with a light meter, but hey, I try.

 

[Marco]

I don't use them, but I've heard of people using xenon lights. They don't give off alot of heat either.

 

[johnndc]

I use the fluorescent shop lights, the 4 feet long ones, and yes, my plants are between inch from the tube to maybe a foot. No more. That's good light for paphs, some phrags like besseae (I think), and obviously good for phals, and even several mini-catts I have that are pratically bleached yellow under them. I've also had some oncs bloom under them too, so that's not bad. But yeah, everything needs to be a foot or closer to the lights. I'm not the light expert, but if you're thinking fluoresent, then then T5, rather than T8s which I have - they're brighter, though more expensive. I just don't know about CFL's. Finally as for set up, yeah, I think a lot of us have fluorescent shop lights hanging from metal shelves, you know those big 6 feet tall shelves, 4 feet across, 18 inches depth. 3 or 4 shevles per unit

 

[littlefrog]

If you want to use clamp on lights, they have compact fluorescent spirals for relatively cheap now. I've seen them in 150W incandescent equivalent for around 8 bucks at the big box store. And I think I bought a clamp-on fixture for 5.97 (or close). Just lighting a frog tank with it, but it is nice and bright.

 

[Heather]

I'm using those CFLs, John...
They're easy if you have, um, a frequently re-arranged sort of space.

 

[kentuckiense]

I have a T12 shoplight setup. I keep it very close to the plants... Some leaves even reach up into the fixture. I wish I had researched it all more... I should've gotten T8s or T5s.

 

[PHRAG]

I guess that is the problem I had with fluorescent lights.

Shelf by shelf, I have measured my current light output. I have two clamp lamps with those CFL bulbs. Maybe I need to get the strongest CFL bulb they make. But by measuring the lux output from those bulbs and converting it to footcandles, I found the bulbs have to be within five to six inches. Now, the falloff of light from those bulbs is really bad. So I calculated that I would need at least five clamp lamps per shelf to use those. That is 30 clamp lamps! Can you imagine the octopus that would create?

So then I thought about shoplight styles. That would require 4 to 6 fixtures, somewhat more manageable, but still a logistical nightmare. With me moving alot, I can't see moving 6 shoplights every time. And the only shelf that has plants that are all the same height is the Phrag shelf. All the other shelves have really tall plants mixed with really short ones. I don't know.

So I started thinking about HID. How hot do these get? I already reach daytime temps of 78f in the greenhouse. I think the lights would bake.

Is there a fluorescent fixture that can hang a couple of feet from the plants and still be effective?

Is there another type of fixture that can hang that far from the plants and still be effective?

 

[kentuckiense]

To be honest, I have no idea. Personally, I'd think a 4 tube T5 fixture would be the best you can get in terms of fluorescent. However, I still have no idea what I'm talking about.

 

[PHRAG]

Me neither, and I feel like I am looking, again, for that magical solution to a problem that has no magical solution. Why can't anything be easy?

 

[kentuckiense]

Build this:

Problem solved. You're welcome.

 

[littlefrog]

A couple of points to ease your troubled mind... 1) remember you are supplementing your light, not using these as a sole source of illumination. As such, you don't need to achieve the full number of footcandles required for plant growth with just the lights. 2) You can make up (to some extent) for light intensity by light duration. You might need 14-16 hours per day of lighting, rather than 12.

HIDs with remote ballasts aren't furnaces... It might work...

If it were me, this is what I would do. Purchase maybe 4 of those clamp lights and the biggest meanest CFLs you can find. Use one for every 2 feet of linear bench, at a height that is convenient for you. One bench only. Of course you can have the light a bit closer to a group of shorter plants, or vice versa. Run this setup for a couple months and see how it works. You will see some improvement, for sure. If by the grace of your deity you are getting too much light (unlikely), you can pull one light out of the row and respace the fixtures, or move them up a few inches. Need more light, there is room for adding another fixture and respacing them closer together. If you are satisfied with the results, buy some lights for the other benches. This way, you aren't spending too much to test the setup.

 

[PHRAG]

Dammit Zach, you're a genius! The answer was staring me in the face the whole time. Maybe I could hire some people to go around collecting spare windows for me. There are a ton of them in the skyscrapers of downtown Phoenix.

:evil:

 

[Heather]

Dammit Zach, you're a genius! The answer was staring me in the face the whole time. Maybe I could hire some people to go around collecting spare windows for me. There are a ton of them in the skyscrapers of downtown Phoenix.

:evil:

Isn't it amusing how we all think? I was at the Kennedy Library a few weeks ago and all I could think about was how well I could grow my plants there.
Zach's suggestion is prettier though.

In all seriousness, I agree with Rob on this one. The thing I like about the clamp on lights is you can maneuver them around based on the height of the plants, something you cannot do with shop lights.

HID seems like overkill to me for your situation....good for the plants though!

 

[Eric Muehlbauer]

I would definitely avoid HID lamps in the set-up you have...even with remote ballasts they get very hot...do you have ventilation in that greenhouse? Even regular fluoreescents can cause a heat buildup....on my plant shelves (3 sets of 4 40w bulbs I keep 2 fans blowing 24 hours a day while the lights are on. Take care, Eric

 

[johnndc]

Rob, I still get confused as to which CFL to buy, how strong, and what kind of socket it goes in - I read that some of the sockets (ballasts) are good enough for a strong CFL, but others aren't. Meaning, do we have to buy some kind of special light socket or what? I"m thinking of getting a few CFLs as well as spot lights for a few plants.