greenhouse lighting question

Discussion in 'Gardening & Plant Propagation' started by pickapeppa, Aug 19, 2005.

  1. pickapeppa

    pickapeppa Well-Known Member

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    We are currently having a debate on which lighting to use in the greenhouse. The two options are: flourescent fixtures with one UV and one regular, or flood lights.

    If anyone has any advice or experience on the matter, I would be interested in any recommendations.

    Would the flood light be enough if it was placed several feet above the plants, or does the lighting need to be 12 in. above the plants regardless of type? How many lights would be needed in a 16 X16 gh full of raised beds? It is a little shaded on the east side by some trees. Light quality is poor in there pretty much year round. :stars:
     
  2. Marcia in MT

    Marcia in MT Well-Known Member Supporter

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    Usual recommendations are for one cool fluorescent tube along with one warm one. This produces the entire spectrum of light, which plants need. The lights need to be set right above the plants, as the intensity drops off pretty quick the farther the leaves are from the fixtures.

    No matter what you use, electricity is *expensive!* Any chance of moving your greenhouse so as to be able to get more sun?
     

  3. rzrubek

    rzrubek Flying Z

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    Do some searching for hydroponics and lighting. You will find talk about metal halide lamps and sodium halide (or something like that) lamps. You will need alot of expensive lamps for that size of greenhouse if you are not getting good sunlight. Reg flourescent lights cannot provide near enough light for plants. Any chance of moving the greenhouse to a better location? Good luck, Randy

    Here you go, this will get you started http://www.sea-of-green.com/store/index.php?cPath=61&osCsid=48ca62912ae37504246f9067cdb12769
     
  4. pickapeppa

    pickapeppa Well-Known Member

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    Well, we really don't have anywhere else for the greenhouse to sit, except right where the garden is. It might still be possible to cut the tree down, it is only going to get bigger and cast more shade, duh! Our electricity rates may not be as high as they are in Montana. Whenever we add something new to our usage the rate changes are usually cost effective. This is an area that I wouldn't mind experimenting with solar in the near future. Thanks for the link, rz, but these fixtures are outside our current budget for the project. I will try the cool and warm fluorescents for now and see how it goes. I was asking about the flood lights because we have leaks that won't hold a seal for some odd reason. Our greenhouse roof is 4 industrial sized skylights. My husband has been up there several years in a row with that black tarry stuff coating everything that could possibly be leaking, and nothing even puts a dent in it. I've given up on the leak proofing. He mentioned that flood lights wouldn't be as likely to corrode as a shop light fixture. Although, I have figured out a way to hang shop lights that will avoid drips directly on them.
     
  5. rzrubek

    rzrubek Flying Z

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    Yeah i figured they were out of reach, i just wanted to illustrate how much the proper lights cost. Outdoor type flood lights would be your best bet as far as corrosion is concerned. Your husband may have to remove and reinstall the skylights in order to get them sealed up, sound like they weren't installed right. Is it possible to just trim the tree? Is it evergreen or decidious? Good luck with it, Randy
     
  6. mightybooboo

    mightybooboo Well-Known Member

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    Then cut the tree now,if its in the early growth stage,it will cost a ton more to cut in a couple years if paying to have it done.

    BooBoo
     
  7. pickapeppa

    pickapeppa Well-Known Member

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    I think the tree might have to stay where it is. It's a half-grown soft maple. We can trim up some of the smaller branches to let in another hours worth of light. That is in the plan. The problem is that we just installed a pool and between the greenhouse and the pool, there just isn't a way to get the tree down without damage. In addition, there is another maple behind this one that shades as well. Come to think of it, there are about 4 trees casting shade from the east side, lol. All blocked in by the pool.

    My husband just decided yesterday to remove the front two skylights (they are tinted a brown shade) and put plexiglass on that front half to allow in more sunlight. He's also replacing the south facing wall with plexiglass, which will also allow in more sunlight than those cloudy poly rolls.

    Between the tree trimming, plexiglass and roof configuration, I think we might only need to add lights to the back half of the space. Randy, how many flood lights do you think I might need for the back 8 x 16 area, and how close should we have them to the tops of the plants? Are there many choices in light qualities as there are with fluorescents? ie, cool, warm, etc.

    My husband was under pressure when building this greenhouse. I'm sure he didn't research info on how to install skylights. We had just gotten married 9 months prior, were expecting a baby and bam, he developed a health condition for which the prognosis was "grave". He made it his mission to fulfill my greenhouse dream in case he didn't make it. Thankfully he survived, and now we are just optimizing on what is already there. He is really good about changing things around if the originals don't work. Being that we are both inexperienced on this subject, there is a lot that doesn't work, lol.