I'm currently looking at a grow light that has florescent tubes. It allows me to choose between a two foot long and four foot long lamp.

Additionally, I can choose between four or eight florescent tubes (long light bulbs) in the lamp.

What is the difference between the amount of tubes? Does having more tubes make a difference? Does this mean that if I purchase the one with eight tubes, that I'll somehow have better plants/plant growth?

I'm trying to ensure a headstart for my short growing season and I grow a lot of peppers and greens. I want to experiment with growing them indoors...please tell me what is the difference between the amount of tubes you choose? Thank you.

Fluorescent lights that are not labeled as "grow" lights will also work just fine. Often they are cheaper as well.

Or does that mean that I'll have to cram all of the plants directly underneath the lamp for them to grow? This is my first time trying to grow with lamps.

I'm also wondering how much they can grow with a light? Can it grow until it produces fruit or seeds?

Trying to produce good-tasting fruit entirely under artificial lighting is another thing entirely. The problem is that the hps lighting you would need will use more electricity than the value of the tomatoes you would produce. I don't know about producing viable seed with fluoros - enough of them will make a fruit or two, but I doubt it would be anything you want to eat.

I'm a sales rep for a hydroponic store as well as an active Hydroponic Indoor gardener. T5 Florescence are the best option for seed starts, cloning, and vegetative growth. I'd absolutely recommend a t5 florescent for your needs. You'll be able to get very healthy and tall starts out of your light. There are two ways to look at your florecent light.

T5's work best when the light is 4-8" from the plants you are growing. They produce little heat. So whatever size light you buy, 4'x1.5' (a 4' 4 lamp system), that is the area you'll be covering very well. So lets go further...

A) Seed starting/cloning/basic veg: In this situation you can raise the light up and cover a larger area because you are not focused on super productive growth. You want your seeds to pop or clones to root and that doesn't require a lot of light. When your plants are growing up, meaning they have rooted, you can leave the light 12" or higher to cover more area but the downside is that your plants may stretch for the light. But that is ok if you plan on going outdoors or wanna just start a bunch of plants for cheap.

B) Productive growing/flowering: Ideally you want that light directly on top of the canopy, 2"-8". Now your light's footprint is as large as the light fixture, but the quality of light is significantly greater and that means the plants in this area will grow rapidly. Your yield will be much greater as well if you choose to flower indoors.

The more lamps, the more area you can cover.

I hope that helps. Sun Leaves Pioneer T5's are GREAT lights. Quantum's BadBoys are really nice too.

T8 for non-fruiting is maybe the most economical depending on the vertical growth of the plant. With greens and lettuce it is a great (and cheap) approach.

Add a little mylar and extend the photons a bit further.

Does this mean that I simply have to raise the height of the lamp above the plants and adjust the height of the lamp depending on what exactly I'd like to do with the plants? (e.g. have them flower, grow peppers, etc?)

And does this mean that the taste will be off because it's indoors and with a lamp?

With flouros, keeping them as close to the plants as possible is key since they lose penetrating power quickly compared to HPS and MH.

With T5's, about an inch to one and a half inches should be correct.
Changing bulb colors will allow flowering.

As for fluorescent fixtures, depending on the fixture style, they usually throw out a useable footprint 6" wider than the fixture is. E.g., if your fixture is 2'x2', then your footprint will be about 3'x3'.

I'm growing six jalapeno plants that are each about 3 ft tall in an ebb and flow system under 216w of flouorescent lighting in a 4' - 4 bulb fixture. It's working marvelously. Product I'm using in optional link URL.

They are the most effcient. They put out more lumens per watt then even the best T5 lighting.

link to it: http://www.tomorrowsgarden.net/node/5

Heat is measured in btu, temperature in degrees. The most efficient lamp has the lowest heat output, HID in this case. Lamp temp is higher, heat output is lower.