I have seedlings that will be brought into the house for Winter. I want to provide light for good growth until next Spring when they will go back outside. Home Depot has a 4 foot shop light that uses 2 T8 bulbs with great reviews for $20. It is grey and in the reviews some suggested painting the reflector white. Home depot carries a 4 foot T8 32 watt, cool white (4000K), LED light bulb. And a 4 ft. T8 32-Watt Daylight Deluxe (6500K) Linear Fluorescent ALTO II Light Bulb (2-Pack).
Lowes carries a 4 foot white fixture with great reviews for $11.98. It uses T12 bulbs. 2-Pack 40-Watt 4-ft Bright White (3500K) or 2-Pack 40-Watt 4-ft Daylight (6500K) or 40-Watt 4-ft Cool White Fluorescent Light Bulbs (4100K) , all under $10. The T8's are energy star rated, the T12's are not.
My question is what would be the best for the seedlings?

@RickCorey has done a lot of research on this subject. Hopefully he'll be along to give some insight, or at least a link to what he's written.

Go ahead Rick, Dave has given you the lead. I will correct your mistakes.

Rick has info about the bulbs in his blog:

http://garden.org/blogs/entry/...

Thank you for the link. I found it very informative. Now it will be much easier to make my decision.

I was "out sick" for several days.

My take is that T12 bulbs are obsolete but still cheaper than T8s. T8s are cheaper to buy than T-5s, and much cheaper to run than T-12s.\

Maybe LED lights will replace all florescent tubes sometime in the future, but I'm going to wait for LED fixtures to keep dropping in price before I buy any.

Both T8 and T12 use new technology similar to "Compact Fluorescent Lights" (CFL), so they are much more efficient than the old-style T-12 bulbs. They also use a different ballast than T-12 fixtures used to use.

In addition, T-8 and T-5 bulbs can be made brighter than T-12s, and that seems to me like a great big thing for growing seedlings. Giving them "plenty" of light seems better than noodging T-12 lights up an inch at a time, trying to keep them super-close to the seedlings to make them effectively brighter.

I know that lots of very experienced people grow many seedlings with nothing brighter than T-12s, but my small setup would be greatly improved by something brighter (and some carpentry to hang them from).

Other T-5 bulbs and some T-8 bulbs were designed not for extra brightness, but for long-life or extra-extra efficiency. You have to read the details if you buy a box of T-5 or T-8 bulbs, and decide whether you want to pay extra for even more brightness or even more efficiency, or pay less up front for the bulbs, or get bulbs that won;t need to be replaced as often.

My "color" advice for starting vegetable seedlings and common flower seedlings is traditional: "one warm bulb and one cool bulb".

Ken, I hope you do correct me, and/or extend these comments into the land of orchid-growing, because I have a caveman approach to lighting seedlings. "Brighter is better." "More photons!" (Maybe African Violets are fussier than seedlings.)

"Some blue spectrum and some red spectrum" gives the plants everything they need for basic growth. Fluorescent lights are never going to give a continuous emission spectrum like the Sun, they only emit "lines" - light at specific frequencies - determined by the particular phosphors they are coated with.

"Broad spectrum" tubes have a tri-phosphor coating that spreads out those "lines" somewhat, but chlorophyll doesn't actually need that. You can grow many plants successfully under sodium lights that emit just one or two sharp lines (as long as they get enough red for proper elongation and enough blue for whatever - blooming?).

Some sources claim that "Grow Lights" are nothing more than "broad spectrum" (tri-phosphor) tubes with a fancy name stenciled on, and a much higher price. They also don't last as long as regular tubes, and are less right. "Give me more photons" - generic photons - for my seedlings, and fancy color spectra for portrait photography!

Ken?

I agree with everything you say, but I use the upper range spectrum, something at or greater than 5000 K. I use T-8's and have eight bulbs per 10x12' greenhouse. They are generally named "Daylight" and/or "Broad-spectrum". I am not only growing orchids but other tropical plants as well (staghorn ferns, fiddle leaf ficus, tillandsia, bromeliads, etc. I also use some LED lights, both reds and blues, but they are terribly expensive, and I use them just for my orchid seedlings. Since I am using my lights out in greenhouses, I only use those fluorescent and LED lights from 3:00 PM until 10:00 PM. My plants need their rest period and I am not trying to force them. I am just supplementing the lack of bright daylight hours.

Did I miss something?

I have a faint recollection of SOMEONE explaining that some plants have more demanding needs than seedlings in the first few weeks or months.

I thought it might have been you talking about orchids ... and I often see African violets as houseplants under those ugly purple lights. I figure there must be SOME reason for people to pay more for an ugly light.

But maybe not! Marketing and advertising are pretty effective at making people pay for things they don't need and wouldn't want if they hadn't been hypnotized.

I agree, Rick. People don't really know what they want/need and when they see those magic words "Gro-Light", they think they are getting something really special. In most cases they are only paying a premium for something that is readily available at the big-box stores. All eight of my fluorescent fixtures are two-tube ones and now I wish I had spent a little more and gone with the four-tube fixtures.

Thank you Rick. You provided me with the info I need. At this time I am going with the T8. The model I am looking at uses 4 bulbs, so I figure on 2 warm and 2 cool. I think I have 3 more weeks before bringing all my plants in.

FOUR T-8 bulbs ... nice! That should be plenty bright enough for just about anything short of growing a row of corn indoors.

And I think it is the best lumens-per-dollar and dollars-per-hour choice available at this time.

I'm envious!

I hope you take and post a photo once it's set up and your plants are under it.

I will post a photo. The nights are getting cooler.

There was a recall at Home Depot of some of the two light shop fixtures.
The bulbs were not held properly in the fixture and had lead to smoking etc.
This was earlier this year.

Some of the shop light fixtures are so cheesy-cheap anymore! I still have a few of my older ones (like from early 1990s) left, out of the 6 that I use for seed starting, and they are SO much sturdier than the newer ones.

Thanks for the information Caroline and weedwhacker. The fixture I am looking at is from Lowes made by Metalux. An electrician friend said that brand makes good products. I didn't care for the reviews on some of Home Depot fixtures. I pray I am making the right decision on this fixture. I have never grown under lights before. This is going to be interesting.

If you're a late sleeper like I am, a timer is a worthwhile investment.

I don't know for sure that irregular day lengths and "sunrise times" confuse plants, but I know that plants don't want to "sleep 'till Noon".

BTW, ONCE I had a brainstorm that I could get more light to some tall plants if I set on 4-foot, 2-tube fixture upright, sitting on the floor, aiming into the foliage.

Then, a while later, i watered heavily because I was going away for a few days. Luckily I happened to smell something funny just before walking out the door. At least one plant overflowed it's saucer and the water (of course) found its way to the point where 120V AC was sitting flat on the floor.

Don't make that mistake!

Thanks for the advise. A timer will be needed.
I sure am glad you found the water and electricity mix before you left.

Me, too!

I was feeling proud of myself for having watered heavily, then stood next to my suitcase at the door thinking "Is there anything I forgot? What's that funny smell?"

Steam coming up from the light fixture.

It reminded me what the British Columbia police were alleged to have said, back in the 1980s, when asked what resources they devoted to tracking down and arresting indoor cannabis growers.

"Oh, we catch THEM when they burn their house down."

Rick -- oops! A couple of friends have offered the advice that I am likely to burn the house down with my grow lights...

Reine -- yes, absolutely use a timer... and give your plants around 16 hrs of light daily, keeping the lights quite close to the plants (an inch or so).

The one thing I really haven't figured out is how to conveniently raise and lower the lights... (Rick ?? or anyone??)

I am planning on hooks and chain. I am using a heavy duty shelf system and will hang the light from the upper shelf and use hooks and chain to adjust distance. I hope this is going to work. I better recheck all the measurements first.