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Are T-12s that bad?

I, like many others here, have started plants indoors only to see them out in to the yard come Spring. I have an old T-12 fixture...with new 6500 K bulbs. It's 4 ft and 2 bulb. I am starting about 100 seeds (overkill..but I want a failsafe for each variety). Can I get by with this lighting set up for about 2 nursery trays of plants? (they fit perfectly under the fixture) Or is a T8 with 4 bulbs that much of an upgrade? I am trying to do the best with the least amount of cash spent...I am not going to spend more than what it costs for the T8.
 
Thanks for chiming in!
 
-Mike
 
T12's work great. Two 4 ft x 2 bulb fixtures would be ideal, keeping them as close to the plants as possible. They can even be touching without burning the plants.
 
A T8 4 ft x 4 bulb vs a T12 4 ft x 2 bulb is no comparison. You can probably do 4 trays under the T8 4 ft x 4 bulb.
 
I thought my old fixture would be fine. It is quite bright. I have them on an adjustable chain so they are pretty much touching the plants (once they sprout). I just didn't know if there was a reason to upgrade to the T8 fixtures.
 
Should be fine.
I will use T12's for starting my plants until they are no longer available.
From my experience T8's can't be right up against the plants or the leaves will burn. With T12's I have had plants grow up in between and against them with nothing more then some purpling on the leaves.
willard3 said:
The problem is that there aren't T12 lamps around much......hard to find. T5 and T8 have replaced them.
Have read they are being phased out, but most of the big box HW stores(at least around here) still have them.
 
Have any of you guys using T-12s tried T-5 fixtures and bulbs?

I think that T-5 bulbs are way more efficient, and cost cheaper per lumen. I just paid about 6 dollars for a T-5 HO 3200K bulb. That is a 54 watt bulb. (Only at 1/3 of my bulbs are 3200K. The rest are 6500K)

T-12 bulb (4 foot, 40W 2,325 lumens) 6500K

T-5 bulb (4 foot, 54W 5000 lumens) 6500K

If you have more lumens for almost the same wattage used, you don't need tour lights as close. I have only had 8ft HO T-12s for general shop lights. I was using T-8s for grow lights till I saw the difference with the little 2 foot HO T-5 fixture. Seedlings just sprang up. Seeing is believing. My Hydro shop guaranteed that if I didn't like the light within 2 weeks, I could bring it back. I kept it.

Also I never had a polished reflector with any T-12 fixtures. My T-5 fixtures have polished reflectors.
 
I wouldn't mind using some t-5's or even some 8's but it would cost me a small fortune to light up 2000 pepper plants. the 12's  work perfect for the setup i'm using. 50 4' shop lights keeps them all happy till I put them in the greenhouse.
 
That was kind of my initial question. I'd rather not have to spend any more money if I get decent growth until the Spring plant out. I got the fixture for free, and the T12 6500K bulbs were like 10-20 bucks. I don't even count that as an expense because I got them last year. T5 fixtures are kind of pricey for a newbie/novice/hobby grower. Even though I always like the best of the best in other hobbies, I hope these little guys grow a bit with the old school bulbs I have.
 
I'm going to be spending enough once Spring hits on soil, boards, bricks, and other landscaping/gardenscaping items.
 
I suffer from a few issues. I have limited space and with my movable shelves have found the t-5's are too close. This makes t-12's perfect since contact with the plants doesn't burn. The more I think about it, my space constraints may be more what makes me biased. If I had great open space like some of the indoor starting setups I see on here, I probably would give the t-5's a good healthy shot to see. Also, I don't tend to want to fix something that is not broken for me.

As many have told me through the years, especially here, "If it works for you, stick with it"

Best of luck with whatever you choose, I am positive you will find someone on here that has had stellar results with whatever you decide to make yours. :D
 
for 4 trays you usually need 4 bulbs of t12, or 3 bulbs of t8, or 3 CFL.
 
t12 fixture 20$ x 2 = 40$
t12 4 bulbs = 8$ (probably have to buy pack of 10, or 2x2)
t12 total 50
t12 output 9.4k lumen
Fluorescent-Dual-Strip-Fixture-Large.gif

 
t8 fixture 20$ x 2 = 40$
t8 4 bulbs = 8$
t8 total 50
t8 output: 10.4k lumen
(they are the same looking as t12)
Fluorescent-Dual-Strip-Fixture-Large.gif

CFL "fixture" 12$
CFL 4 bulb 32$
CFL total 44
CFL output 11.2k (you get full spectrum which is good aswell)
 
MwROcwI.jpg

detail on cfl "fixture" ( power strip 4$ + light socket to plug adapters 8$ + some alum foil from your kitchen free?)
 
 
as you can see CFL does best bang for buck but is a little ghetto looking, make your own choices based on the data.
 
Any light will "work". I dont think 4 trays or 100 plants will enjoy 3, t8s let alone 2, t12s. A window "will work". Im probably missing something but id want more light. Plants want more light or else summer sun wouldt be a big deal.
 
I got about 80% germination, and the 2 trays of seedling in root riot plugs are under my one t12 fixture with 2 bulbs for the past two weeks. I have them as close as they can get to the seedlings. Most have only the cotyledons, but about 20 are showing signs of true leaves forming. I lost a few due to the plugs drying up, so I'm down to about 70 potential transplants to the 4" pots that fit in a nursery tray. I figure 3 trays is what I'll end up with. To keep the lights close enough, I will need a 2nd fixture. I've read a ton, and would love a T5 4 ft. 4 light fixture, but can't seem to get an accurate price on one. What is the best deal for a T5? Is it that big of an upgrade, or should I just grab another T12/T8 2 light fixture? I know...I know..there's no exact answer. I appreciate all of your insights.
 
-Mike
 
Go to lowes and look for a T8 4 bulb fixture, the plug in type, I found mine for $40 or so, I found the bulbs themselves for around $15 in total, and it puts out 13,000 lumens. I have grown 4 1020 flats under that one fixture. So I put them in the greenhouse in a small "cage" I made, ( wood lined with aluminum foil covering all sides) So as little light escapes the setup. So it can be done with T8's, but it can be done with T12's as well. You may be able to find higher lumen per watt bulbs for the T12's
 
http://www.lowes.com/pd_283285-1390-GU9804-T8-BKSS_1z0y5pd+1z11ovb__?productId=1208545&Ns=p_product_qty_sales_dollar|1&pl=1&currentURL=%3FNs%3Dp_product_qty_sales_dollar|1%26page%3D1&facetInfo=Fluorescent%20shop%20light
 
These are the bulbs I use but my Lowes had them in 2 bulb boxes. I'm sure your lowes or Home depot would as well!
 
http://www.lowes.com/pd_105826-16841-21763_1z0yax2+1z0ybpn__?productId=4564466&Ns=p_product_qty_sales_dollar|1&pl=1&currentURL=%3FNs%3Dp_product_qty_sales_dollar|1%26page%3D1&facetInfo=48.0
 
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