When it comes to lights, more is better. ;) Definitely 2 and with 30" of width, 3 would be even better. That way you would have full coverage of even the outside edges of the shelf.

Dave

Johndoug, there's an additional advantaged to be gained by using 2 fluorescent tubes - one can be cool and the other warm.

This will broaden the spectrum without buying a wide-spectrum tube. I haven't priced "grow lights" lately but buying two of the "regulars" may save you some money. There's very little difference in the price of the 1- or 2-light fixtures.

Steve

Actually, i probably didn't word my post correct. I was planning one light fixture. This light fixture has 2 lights in it. If i add a second light fixture, that would have 4 bulbs.

Another question i forgot to ask. I built shelves two levels high, and i was planning to seal with plastic around the shelves. I'll post a picture tonight. My worry is about the humidity in the area, and even drips from the bottom of a pot onto the flourescent light fixture. Has anyone had problems with this?

More light the better.

Patti
www.gardengirltv.com

Instead of worry about drips, place your containers in shallow pans (like small cat litter pans). You can slide them out easily, like drawers, to see what's going on.

Cheap roll-down vinyl shades on the outside of your shelf will do plenty to hold in humidity at night, if you're that worried about it. Until seeds germinate, covering them with wet newspapers is the next best thing to having plastic domes. Once seeds are up, too much humidity can lead to problems.

Here is a link that might be useful: my website

Wow...I'm using 4 in 22" and was thinking about adding another.

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For a 24" width I used 4 lights. Two won't do a good job.

tom

I use 3 overdriven fixtures (6 tubes) for the same space.

Macheske,

GREAT job on your stand. Thanks for posting the pics.

I just read somewhere that if you use flourescent bulbs you need two different type, on emits red and the other blue, This is a Quote from that site below.

"FLUORESCENT BULBS produce two to three times more light than incandescent bulbs for the same amount of energy. They are the most inexpensive lights for indoor gardening. The color of light produced is determined by the phosphor coating on the inside of the bulb. Cool white bulbs are a good source of blue and yellow-green light, but are a poor source of red light. They are used for interior lighting in schools and office buildings, and are the most commonly available type of fluorescent bulb. Plants grown under cool white bulbs will be stocky or even slightly stunted. Warm white bulbs emit plenty of orange and red light, but less light in the blue and green spectrum. If you are growing seedlings under 2-bulb fluorescent fixtures, you can usually achieve a good color balance by combining one cool white and one warm white bulb. "

Interesting, I hope this helps.

Here is a link that might be useful: http://www.gardeners.com/Gardening+Under+Lights/5080,default,pg.html?SC=LNA7002A

This is my setup. I use only cool white bulbs that I buy in boxes of ten at Home Depot. Everything grows fine, but mixing the bulb types might be better, I don't know. I use insulating foam as reflectors to concentrate the light.

Here is a link that might be useful: {{gwi:9572}}

There is a point where you get a bit of overkill. Two fixtures are better than one. Are three, four or five going to provide any real difference in plant performance? I tend to doubt it especially considering the fact that you need to raise the lights as the plants grow and here are other means like plant spacing or using reflective surfaces to get light through an increasingly dense plant canopy.

When you are building this stand, John, you would be better advised to adjust the stand dimentions so that it will meet your future needs. Most of the double bulb fixtures that people use are 4 foot long. Therefore, I'd make the length of the stand slightly longer so that the fixtures arent pinched within the framework as you will need to raise or lower them. iprefer a dowel rod above each fixture with finishing nails inserted in the ends. Then with 2 sets of chain draped over each end of the structure you can simply slip the nail out of one chain link and into another to adjust height.

But your 30" width is a bit confusing. Standard flats are 11" x 22". Newly germinated plants (first two weeks) need to have the lights just above the leaf canopy and so placing two trays/shelf parallel with the light tubes makes good sense. Once plants are forming a second set of leaves you should transplant them into larger cell packs unless you have already wasted space under lights by starting seeds in larger cells. My point is that at this next growth stage you can get reasonably good light coverage by placing 5 trays/shelf perpendicular to the light tubes. For this tray positioning a 23" wide shelf will work fine. You can staple a 3/8" cord around the shelf perimeter and just cut open a larger garbage bag as a liner. The cord will keep water contained nd the plastic will hold small amounts of water until it evaporates.

I would not recommend watering plants on the shelves. You'll need to get them out from beneath the lights to do a good job and it can get a bit messy. I like to use a combination of watering methods: Bottom watering by wicking action, sprinkling can and mister for fragile plants. All of these watering methods are best done in different location. Once trays are allowed to drain of excess water set them centrally on an opened section of your favorite newspaper and by extending your arms under the tray and usung your hands to fold up the opposite newspaper corners around the tray corners you can transport trys accross your house without drips as long as you gently tip the tray away from you toward the folded corners.

I can provide you with some guidelines for different 3 tier stands. I have two wooden frame stands, one simply cheap PVC frame stand and a ceiling supported 33 flat setup that get me through the "Free heat" phase of plant starting. After that the trade off of supplemental heat
for free light begins to get stressing.

This is my setup for my peppers, I use only the cool whites also you do not need anything more than the cheapest bulbs you can find if you are only growing them as transplants for the garden. I keep my seedlings right under the lights about an inch away. I end up with three fixtures per shelf when all the seedlings are in there 4" pots. Racks are 48x18x74.

Dale

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The number of lights is really not an effective way of determining how much light to use. Are you growing seedlings? or transplants? or will you finish your crop under lights? As a general rule of thumb leafy plants like spinach and leaf lettuce need approximately 2500 lumens per square foot and fruiting/flowering plants require about 10,000 lumens per sq foot. As with anything there are exceptions to the rule. Unless you have a sun in your basement the plants can probably handle the amount of light. Where numerous lights becomes problematic is if there is too much heat.

Hey guys.

Thanks so much for the responses and pictures. I couldn't see them on my home computer, and it wasn't until i opened this from work that i saw them. Picture of my shelves to date is below. They are only 25 inches deep.

The question i have now is what bulbs. I bought half of 4100 "cool white" that i can't return. Should i buy the 6500 or the 5200 for the other half of the lights? Thanks again.

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You can use one of the regular bulbs and go to Home depot and get there 4' plant bulb for $10. I use the 4' fixtures on chains to adjust 2" above the tops. Been doing it for over 30 yrs with good success. A real cheap way of doing it also is just put good sheetrock anchors in the ceiling with hooks and anchors with the chain and lights. You really need it just 5 or 6 weeks per year anyway.

Dale,

Did you say you can keep your plants in 4" containers until plant out? When do you start your pepper plants again?

I'm curious because I've got some that are growing so fast they are outgrowing 4" square containers fast. I put up tons of Mylar on my basement walls and it has made all the difference in the world. We have EXACTLY the same set-up light and shelf wise. :)

Chris

Holy cow, Doug!

I get the impression this will be your first year starting plants. You're really jumping in deep with a setup that size the first year, not that that's a bad thing. I assume you're planning on twenty flats at two flats per hole, you'll definitely need two lights, if not three. If you're only doing one flat per hole you may get away with one light per hole but would be better off with two. It's a bit late now but I agree with others that going with a 48 inch setup would be better than the 24 inchers you'll have to use with your current design.

My first year was pretty sad. I had one 48 inch light on a frame sitting on a work bench. In the setup, I tried to grow FOUR flats. You can guess how well that worked. If you go back one page and select my post titled "my starting setup is ready - pics" you can see how I start plants. the frame on the left side is the original frame from my first year. I'm growing ten flats under this setup this year.

Be sure to post pics when it's all together and growing your plants!

bill,

it will be my second year doing a decent amount of plants. i do plan on going with the 48's. have them bought just need to put them up. total length is 144, so i'll have 3 wide, and i guess i'll double up and have 6 fixtures top and bottom.

i didn't want to add on next year, so i just dove in deep like you mentioned. last year, i put a few boxes on the floor, and laid two 2x4's on top. then i put a few boxes on the 2x4's, and laid more 2x4's on top of those boxes, making 2 stories/levels. it worked pretty good actually, for little to no costs. i used spotlight type grow lights, which i wasn't happy with.

i'll be sure to post when i have things growing.