you wont be able to grow more than 1 or at most 2 plants with those. id go with long 4 foot tubes and use em vertically so you can get light to as much plant as possible. or if you grow your plants horizontally you could max your light eff. just make a square out of wood 2foot by 2foot, then put chicken wire over it(making it look like a tennis racjet.) attach this to the top of your pot about a foot off it and train your plant to grow horizontally. then cut off all the extra growth

I have the same setup exactly (minus the hydro) and I've had no problem growing tomatoes with it. What kind of tomatoes are you planning to grow? I would stick to dwarf determinate varieties. If you use a fixture with a reflector, the light should cover a 3x3 foot area and you can grow more than 2 dwarf tomato plants under it.

I have a similar deal and am looking into lighting now. I have two tomato plants in a solarium facing the north. There is less light now that it's changing seasons and the weather is colder. What is CFL (150watts)?

I'm looking into cool white fluorescents.

Any help would be appreciated.

Thanks,
Sarah

Just thought I'd throw my two cents in since I've been experimenting recently with lighting while growing tomato plants from seed. I have two 4 foot shoplights, each having 1 Cool White and 1 Sylvania Gro-lux tube.

I tried using a 150-watt CFL (compact flourescent) but the plant I tried using it on didn't respond well at all to it. At first I had the CFL about 2 inches above the plant and it started basically baking the top leaves. I thought it was mold at first but realized the light was cooking the plant. After I raised the CFL to about 6 inches above the plant it started growing in an odd way. The top leaves were reaching straight up towards the light but the plant itself did not grow much taller.

On the other hand, I had set two plants under each 4 ft. shoplight and they have grown very nicely. They are tall and bushy for the most part. I transplanted them to 10" pots when they were between 3 to 4 1/2 inches tall on October 22. Today (Nov. 2nd) the tallest is 7 1/2 inches with the others not far behind, except for the one that had been under the CFL. And that one is about 5 inches or so tall.

For vegetative growing flourescents in shoplights work great. The problem is flowering/fruiting plants need more intense light according to alot of grow guides I've read. I'm going to try it with my shoplights anyways as an experiment to see if I can get anything to produce fruit/vegetables. I live in an apartment and can't justify the expense of a Metal Halide or High Pressure Sodium system. So I'm having fun seeing what I can grow under flourescents.

Good luck to all those growing indoors under lights, Jeff

Are we talking about the 42W spirals sold as 150W equivalent? Or the monster 150W CFLs which are about a foot long?

I used the 42-watt spiral that puts off 150-watts according to the packaging. I'm confused about CFL's now. Didn't really realize they come in tubes also. It would make sense though that a CFL tube would work better than the spiral. I think with the spiral all the light was too concentrated in one small area on a small plant.

BTW, that plant is responding better now that it's under the shoplight with the other plants.

Jeff

Well that's Jeff's bulb identified. I suspect the OP is referring to the monster 150W ones?

Anyway, a quick lesson on CFLs. Stands for Compact Fluorescent Light. All it means is that the big straight tube is bent up into a more compact shape. The technology is the same, although the tubes are generally thinner, T4 or T5 size. Sometimes they come with a built-in electronic ballast and you can just screw them into a standard bulb holder. This type is often labelled with the wattage of the equivalent incandescent bulb, ignore this information for plant purposes.

A compact fluorescent spiral bulb is fine for growing seedlings, it is convenient for lighting a small area such as inside a propagator. But you are correct that the light needs to be spread out somewhat because it is such a compact bulb. I use it about a foot from the seed trays inside a white propagator so the light is very even over all the trays. For providing moderate light intensity over a larger area, straight-tube fluorescents are better since a wider range (of colours and spectrums) is available, they are cheaper (for the same temperature and spectrum), they last longer (roughly twice as long), and they are more efficient (the best T5 and T8 bulbs produce about 50% more light for the same power).

Jeff, when it says a 42w spiral CFL is equivalent to 150w, it's just a marketing gimmick and all it really means is it's as bright as 150w incandescent bulb (for comparison sake), but it is still just a 42w bulb. It does not have the same high lumen output as a 150w CFL.

The one I was referring to is the monster 150w CFL (the "REAL" 150w). It is extremely bright. When I first got it, it hurt my eyes to look at it and almost triggered a migraine, but my plants love it and bloom their little heads off under it. This is not a light where you can grow plants right up against it like you can with the tubes, because it WILL fry your plants. It needs to be kept about a foot away from your plants, as Shrubs mentioned. You can get away with it a little closer, but if it's too close you'll get crispy foliage.

It's fine for growing small patio-type tomato plants. How you decide if you should go with fluorescent tubes or a CFL, it all depends on your growing space. Use the CFL wherever you can't fit 4 foot shoplights and need more light in a smaller space. It is ideal for a 2-3 foot growing area.

I learned some important information today about CFL's. Thanks Shrubs_N_Bulbs and Dana.

It sounds like the "real" CFL's might be better for flowering/fruiting plants than regular shoplight flourescents. Please correct me if I'm wrong.

Just curious, are these "real" CFL's available at places like Menards or would I have to buy them on-line?

Thanks for the advice. I have a feeling you helped Padma out also (the OP).

Jeff

shop lights are by far better if you use the same amount of wattage as compact flourescents. just run them vertically as close as you can to the plants, this way even the bottom gets light, plus since they run cooler you can get them closer,almost touching sometimes.

Thanks utsharpie. I have my shoplights hanging over the plants. They're doing well. Not sure how I could hang them vertically with the set-up I have now. But for future reference that'll be something for me to ponder and work on. Appreciate the advice, Jeff

As I said before, two good 2x40W (or 2x32W or 2x34W) shoplights will put out a lot more light than a 150W CFL and last a lot longer. Two old T12 shoplights will put out the same, or even less, light as the CFL. The CFL will also lose 20%-30% of its light as it ages, while a good fluorescent tube will lose 5%-10%. The CFL will be about half as bright at the straight tubes by the end of its short life.

So the choice is whether you want a single bulb to deal with or four tubes in two separate lamps. Use the single bulb if you need really intense light on a small area (want your Ferocactus to flower at Christmas?), otherwise you will get more light for your money with some good shoplights.

I agree with Shrubs and also said this before, that it's better for smaller growing areas and if you need more intense light in a smaller space. This would be better for someone in an apt. with limited space. I have it in 3 foot windowsill where I use it to supplement natural light. Obviously I can't fit 4 foot shoplights there. But I also use shoplights in a larger growing area where I have more room for it.

CFLs should be replaced every 1.5 - 2 years. That's confirmed by a hydroponics dealer who sells them and the manufacturer. That's good enough to me.

You really need 400, 600, or 1000 W HPS or Halide to do tomatoes unless you're talking a single plant.

The important thing to look for is the light spectrum. Fruit or flowering plants require red light and many fluorescents use only blue. Foliage plants do well with only blue. A fuller spectrum including the red is the best choice, brightness is not the issue.