Thanks for the info Art!

I'm planning on growing my tomato and pepper plants indoors for about a month or two then bring them outside when the weather gets warm. I don't want them to start flowering yet so would a 5,000 lux light setup work just fine for now?

I guess if I knew the exact lux output from my light setup I could figure out if it would be best to put them outside or keep them in. A light meter sounds very handy.

oilrigg,

First of all let me say that I don't grow vegetables under lights, just flowers. So, I'm probably not the best one to give you suggestions :-) If tomato plants are anything like the flowering plants I grow, keeping the lighting low may not be a good idea. My guess is that the tomato plants would simply react to the low light by stretching out, reaching for more light. That of course would cause the plants to grow tall and leggy. And, if you increase the lighting, I don't know how long you could keep the plants from trying to flower :-) I do think that growing them in a cool area would be helpful.

I don't know how far your lights are from the plants but your 1600 lumen CFL's are probably already giving them more than 5000 lux. If you don't want your plants to flower and they're looking healthy, you might be just fine to stick with what you have and keep the plants inside.

One good thing (about tomatoes) is that if the plants do get a little leggy, you can always plant them deeper, when you move them outside. Anyway, sorry I can't be of more help but maybe someone with tomato growing experience will come along with some better ideas.

Art

Art,

I think if it starts flowering I would probably prune it back and remove any flowers. But I don't think it would flower for another 2 months and by that time I should be able to leave them outside.

The distance varies. The closest is about 5" while the furthest is maybe 12-15" away.

I'm not sure what the lumen to lux conversion is but if I have 4 1600 lumen CFLs, would my total output be 6400 lumens?

I did plant my tomato and pepper seedlings deeper after they sprouted. I have some tomatoes growing faster than others and some which seem to not grow at all, which is why I was thinking that my lights were inadequate.

Thanks for the info Art.

"I'm not sure what the lumen to lux conversion is but if I have 4 1600 lumen CFLs, would my total output be 6400 lumens? "

Well, yes you would have a total of 6400 lumens but not in any one area over your plants. Unless, of course, the four bulbs were all in a small bundle where they would act, more or less, as one large bulb. Normally, when you're using several bulbs, they're spaced apart to cover a larger area over several plants. Just as four 100 watt light bulbs separated some distance apart would have a different effect on a light meter than one 400 watt bulb.

Can i use a regular light bulb for light

What your plants get out of the bulbs depends on how close the bulbs are to the plants. Standard fluorescent bulbs lose 4 times the power if that distance is doubled. There is an inverse square involved here. A standard photographer's light meter can be a big help.

". Standard fluorescent bulbs lose 4 times the power if that distance is doubled. There is an inverse square involved here. "

Wrong. The inverse square relationship only applies to a point source of light. A single fluorescent tube roughly approximates a linear source of light with a simple inverse relationship. And, many long fluorescent tubes next to each roughly approximates a planar source of light, for which, the light intensity is constant with distance.

So youre the expert. Whatever you say, but I will continue to successfully grow my plants under lights according to my own understanding, something has worked for me for decades. I have to admit I am still not on your scale; so sales mean different things to me than to a "real" expert like you.

I suppose it is best that I leave this topic altogether. You have the whole thing to yourself as far as I am concerned.

👧👧🧓

Hi Sam,

I am still trying to figure out some way I can be offended by those three little people. I can't think of any way, and that offends me no end. (Grin)

I bought 2-bulb T8 fluorescent shoplights a long time ago (2005 & 2006) in Maine and I still use them in our basement utility room here in Kansas to grow plants.

I actually have a lot to learn about growing plants under lights. That doesn't offend me, and kind of gives me a sense of optimism. Lot's of "room to grow" for me, if not for the plants.

ZM