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3/3/2003 7:07:00 PM
just beginning

Am an experienced outside organic gardener who struggles to produce own transplants each spring. I've used shop lights with cool white bulbs for years in combination with a cold frame outside. My biggest problems have been the relative height difference of every vegetable. For instance today I started all my onions, leeks and celery. Adjusting long shop lights to respond to fast growing allium and slow growing umbelliferae is a hassle. Also, certain plants get real leggy (tomato and squash). In general I'm not real happy with the quality of my transplants. I do not think I need HPS; just metal halide. I need enough watts to cover up to (6) 10x20 flats at any one time. Depending on the arrangement of the flats, I need to cover either 5.5 or 7.5 sq ft. Either a 250 or 400 watt bulb might work; I think. I also need to hang it from my basement celing. Any advice would be greatly appreciated
The Green Thumbs
3/3/2003 11:30:00 PM
Re: just beginning

Forgive me if I'm wrong, but I'm pretty sure the only question you have is regarding what we would suggest for a light. Given the dimensions that you provided, I would suggest a 250w MH system. That system alone is designed to cover up to 9 sq ft. I think the 400w MH light system would be overkill, as it is designed to cover 25 sq ft. Also, if you are just growing to transplant, it sounds like your plants aren't getting that tall before you transplant them. Plants in their early growth stage don't need high amounts of light anyway.

If you have any more questions as to what light produces what, check out our catalog that you can download. On the left menu click on "Request Catalog", and download our full catalog. On page 12, you will see a complete light chart that covers lumen output, and area coverage.
3/4/2003 11:46:00 AM
Re: just beginning

Do you think In need to replace my cool whites with full spectrums flourecents? Will this take care of the legginess? Do I need a 250w metal halide. Some of my plants will be under light conceivably for 12 weeks. Peppers, eggplants, and tomatoes started this early can get 12'' high. Is this considered "early growth" stages. Do this need require high amounts of light?
The Green Thumbs
3/4/2003 1:01:00 PM
Re: just beginning

If you are not transplanting until some of the plants are 12" high, then you will definitely need something more than cool whites. You should think about getting a 250w MH system. The cool whites will be sufficient until the plants get to about 4" high (or 2 sets of leaves have emerged, whatever comes first). The plants should then be subjected to the MH light. I almost guarantee that this should stop the legginess, as the plants will be getting more lumen output from the MH light.
9/8/2003 2:25:00 AM
Re: just beginning

I may be out of my league here, but I have been doing a fair amount of research into starting out an indoor tomatoe garden and so far I have found other interesting discussions concerning "stretching" if I am correct this is what you mean by "legginess" kind of thinning and sparce growth.

Taking into consideration the square footage of your provided dimensions 5.5'x 7.5' I would round it off to 6'x8' and that would mean for roughly 48 square feet you would need at least 50,000 lumens requiring a 400w HPS lamp and I would suggest using an enhanced HPS 400watt bulb suspended 2'-5' above the plants. The enhanced HPS provides a wider blue spectrum which will inhibit a more robust vegetative growth, stronger stalks and branches and will prevent the legginess or stretching of the stalks themselves.
9/8/2003 7:26:00 AM
Re: just beginning

actually, Jesse's square footage is "5.5 OR 7.5 sq ft" not 5.5 BY 7.5, so the 250w MH would be just fine.

also, yes the enhanced HPS puts out a blue spectrum, but it doesn't produce enough lumen output in the blue spectrum to make it worth your while. if you are primarily looking to promote vegatative growth, then MH is the way to go, as that's what it's designed for. studies will always show better results using straight MH (for vegatative growth) and then straight HPS (for flower/fruiting growth) over using an enhanced HPS for veg.

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