tedln
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Building a light box?

I built a small light box this past spring using an under the counter fluorescent fixture which was only 18" long with two bulbs. It worked, but just barely. It didn't provide as much light as the seedlings wanted or needed.

I will build a larger box this winter for my spring seedlings using two standard sized ceiling fixtures mounted side by side with two bulbs each. Does anyone know what the width and length of the standard fixtures is? What bulbs should I use?

I will build the fixture assembly for the bulbs to be only 3" above the seed trays during germinating and early growth and elevate the fixtures as the plants grow. Any other special requirements for the bulbs, fixtures, distance between bulbs and plants?

I don't plan on providing heat pads, but the seeding trays will be sitting on a rubber surface on top of a heavy metal work bench which is enclosed underneath. I plan on using an incandescent light in the enclosed space underneath the seeding trays to maintain a growing surface temp of about 80 degrees during germination. Does that sound about right?

The fixtures will be on a timer set for sixteen hours on and eight hours off each day. The incandescent bulb will stay on to maintain bottom heat until all the seeds have germinated.

Ted

TZ -OH6
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Shop light tubes are 48", so add a few more inches for the ends of the fixtures. Width varies depending on the reflector. Unless you need a tight box to keep heat in, I have found it easy to simply lean reflective materials around the lights (foil covered cardboard etc.) It makes it easier to remove the "walls" to work with the plants, raise the lights etc. and it provides some openings for convective air flow to keep humidity down. Its also good for off season storage.

Of the off-the-shelf standard tubes, the 6,000K (6300K?) daylight tubes are the most energy efficient for seedlings in that they produce more blue light for the little plants. You should be able to find them at Lowes/HD.

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gixxerific
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Th O.D. of my main lighting units is 48' 1/8", that is the dimension of my light housing.

I would also recommend the blue spectrum (I want to say it is 6500K) of lights sold at Lowe's and HD etc. I would also recommend T-8 at a minimum they are high output low consumption. I would really recommend T-5 which are very high output and very low power consumption. Just because they are smaller bulbs don't let that fool ya.

I want to go with some HO T-5's if I can afford the bulbs this winter. I can run them with my setup. Right now I have T-10's (or is it T-12's) and T-8's. The T-8's put off more light amazingly with a smaller bulb surface.

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Halfway
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I used a 48" fixture with 2 bulbs. Shop between lowes, HD, Menards, Ace etc. for the best price. You should be able to get a great fixture for 10 buck or less. Don't pay the typical 25-35, they will go on sale.

Bulbs are rated at 6500k.

I also set my timers for 16 on / 8 off and kept the bulbs between 2-4 inches above the plants.

My starters did very, very well and the neighbors I shared them with were all thrilled at the size and health of them.

I also use them for lettuce and spices in the heat of summer as the basement stays around 58-60 degrees. Since the bulbs are blue wave (ideal for vegetative growth), the lettuce and spices do well and do not have a need to flower.

I am seriously looking into hydroponics to extend my gardening throughout the winter.

Hope that helps. 8)

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Halfway
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Ted, also keep in mind the need for a fan in the grow area. I ended up with a medium size oscillating fan that covers the whole room and "sideswipes" the plants providing a gentle breeze toughening their stems.

Small fans work well, but I wanted more coverage of the whole room to prevent stale air.

Best of success!

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gixxerific
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My starters also did very well with the 6500K lights. They will tell you that you need the red spectrum for flowering or fruiting. But I had tomatoes with tiny fruit on them under my "blue's"

Ted my main setup is 2 separate 4 bulb 48" units. They will take 4 flats under them each. I also ran out of room and bought two more 2 bulb setups which I would like to build something to make them work like a four bulb system. Basically it will just be a plywood top to mount them to.

https://i272.photobucket.com/albums/jj185/gixxerific/Gardening/DSC03356.jpg

You can see in the pic above I have a small efficient oil based heater I used to heat mine with.

Just some ideas hope this helps.

P.S. the heating mats work wonders and don't use much power. I started using them halfway through last seed starting season and wish I would have had it the whole time. :wink:

tedln
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I lucked out on the lights. The wife and I went to our little country church this morning to help prepare it for the 107 th yearly homecoming tomorrow morning. I remembered we had replaced all of the old fluorescent fixtures with the big ballasts in the sanctuary during the summer. I assumed the old fixtures had been carried to the dump ground. I was wrong. The old fixtures were stuck in the cardboard boxes the new ones came in and stored until someone was ready to make a trip to the dump. They all still have the plastic dispersal lenses and they are in good shape.

I now have as many fixtures as I need with the remaining heading for the Habitat For Humanity retail store for resale.

Ted

tedln
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Dono,

Did you find a place with the heating pads reasonably priced? Forty+ dollars is a little expensive for what you are getting. and then you need two of them to cover most areas.

Also, did you find reasonably priced seeding pots and trays anywhere on the internet? Considering the costs of some of the required materials, it would be cheaper to drive to southern Florida, plant my seed in a roadside ditch, stay in a motel, and dig them up in six weeks and head home.

Ted

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applestar
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It sounds like your project is well on its way! :D

Ted, I suspect you're going to want neat and ordered look of identical containers, but [url=https://www.helpfulgardener.com/forum/viewtopic.php?p=117566]this thread[/url] may give you some ideas anyway. :wink:

tedln
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Applestar,

You know me pretty well. I do have a tendency to want everything lined up perfectly and looking like little toy soldiers in battle formation. I am a little more relaxed about my garden though. That was a good thread and I read it when it was originally posted. I have containers from tiny to huge. I have sour creme, cottage cheese, milk, and yogurt containers. I have containers in every color of the rainbow. I still have experimented with newspaper containers and have the method pretty well mastered. I just need to buy a few newspapers and I am ready to start a container factory. With all that said, I'm afraid my personality will win out and I will have the neat and orderly containers of equal size when my plants are germinating.

Thank You

Ted

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engineeredgarden
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Ted - I have constructed 4 completely different enclosed systems in the past, and am partial to the T8 light fixtures. A combination of cool white and daylight bulbs works really well for me.

EG



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