Lights for seed starting

[imp]

I think my head ache is from trying to read and understand all the stuff on t8, t5 and LED lights for seed starting!! And, I am still not sure what would be best. So much of the information is just not clear to me.

My shelves are 4 foot long, so probably need 4 foot long lights?, maybe for 2 shelves.

Any suggestions, other than some ibuprofen?

[ContainerTed]

I use 4 foot T12 fixtures from Lowes at about $12 bucks for a two light fixture. I fill these with "Daylight" bulbs with 6500 kelvin output. It does the job for me. 10 daylight bulbs for about $40 is reasonable as they last for about 3 or more years.

Tomato seedlings don't care about light spectrums. They want the sun which is full spectrum and the "Daylight" bulbs take care of that. Nothing complicated to get good transplants.

All that other stuff is meant to get you to buy something that will increase the profit margin of someone's bottom line. Don't fall for the hype on supposedly "new technology". Mother Nature has been at the same technological level for a long time.

[luigiwu]

I have the T8s. I think my restaurant shelves are 18-inches deep so I need two sets of shoplights per shelf (4x T8 bulbs total per shelf!)

[Worth1]

Originally Posted by ContainerTed

I use 4 foot T12 fixtures from Lowes at about $12 bucks for a two light fixture. I fill these with "Daylight" bulbs with 6500 kelvin output. It does the job for me. 10 daylight bulbs for about $40 is reasonable as they last for about 3 or more years.

Tomato seedlings don't care about light spectrums. They want the sun which is full spectrum and the "Daylight" bulbs take care of that. Nothing complicated to get good transplants.

All that other stuff is meant to get you to buy something that will increase the profit margin of someone's bottom line. Don't fall for the hype on supposedly "new technology". Mother Nature has been at the same technological level for a long time.

I totally agree with Ted.
What else is there to say.


Worth

[Cole_Robbie]

I would probably make a simple fixture by using a hole saw to drill about four holes in a 4' shelf board, and mount ceramic sockets through those holes, wired in series. Then put a splitter in each socket so it would fit two cfl bulbs. The 150 'watt equivalent' would be fine. They make bigger ones, too. The sockets are like $2; the splitters are less than a dollar. Wire is cheap. You can use an old cord cut off anything, or a cheap extension cord to plug it in. Making your own fixture is the way to get the most for your money.

[Worth1]

Originally Posted by Cole_Robbie

I would probably make a simple fixture by using a hole saw to drill about four holes in a 4' shelf board, and mount ceramic sockets through those holes, wired in series. Then put a splitter in each socket so it would fit two cfl bulbs. The 150 'watt equivalent' would be fine. They make bigger ones, too. The sockets are like $2; the splitters are less than a dollar. Wire is cheap. You can use an old cord cut off anything, or a cheap extension cord to plug it in. Making your own fixture is the way to get the most for your money.

I agree but many people cant do this sort of thing or are afraid to.
I wish we could all get together and teach and help each other with a lot of this stuff.
It is so easy for some of us but not others.
I wish I could come to everyone's house that needed help and help them but I cant.
Worth

[dmforcier]

How deep are your shelves, Suzy? Double T12s might be all that fit, and are cost effective from the POV of the cost of the fixtures.

IMO if you have 12" deep shelves, a 4' 4 lamp T8 fixture would be better. Brighter and while initially more $$, considerably less to operate than the equivalent T12.

LEDs I don't know - especially the recent cost curve. They have always been more expensive.

[AlittleSalt]

I use four T12s and a T8 because that's what I have

They work well.

[JosephineRose]

Speaking of which, has anyone ever had the experience of grow lights actually drying out the plants themselves? I have a four bulb fixture about 1-2" above some tomato and basil plants, and I swear it is burning the leaves and they are shriveling and dying. The lower leaves literally dry to paper.

I'm using four FT24T5 bulbs, all of which are 6400K. In contrast, the fixture below this one is running four T12 bulbs, 2 cool, 2 warm, and the plants seem to love it. The seedlings growing under the T12 bulbs outperform the seedlings under the T5.

I'm thinking I need to swap two bulbs on the T5 to 2700K. Thoughts?

[schill93]

I purchased a 4 bulb 4ft. T5 light, and I purchased some T8's, to compare. I am glad I waited before purchasing a second T5, as it throws off a lot of heat in the small 10 x 10 room it is in. So I purchased more T8's for the other two shelves.

If you were putting them a colder area like an unheated garage, then the T5 would be beneficial and if it got very cold where you lived You could build some kind of reflective enclosure around it, and they would stay toasty warm with the T5.

I haven't noticed the T5's burning the tips when I have them very close, and I have had them very close. As far as growing power, I can't voice an opinion on that as I move them around too much.

[dmforcier]

Originally Posted by JosephineRose

I'm using four FT24T5 bulbs, all of which are 6400K. In contrast, the fixture below this one is running four T12 bulbs, 2 cool, 2 warm, and the plants seem to love it. The seedlings growing under the T12 bulbs outperform the seedlings under the T5.

I used to be able to let my plants grow up into and past T12 tubes. T8s aren't that cool and will scorch a leaf in contact. T5s are worse. Back the fixture off and give it at least 2". See how that does. If it still scorches, back it off some more.

And be sure to use a fan to give some air circulation.

I'm thinking I need to swap two bulbs on the T5 to 2700K. Thoughts?

Why? If 'temperature' correlated to heat output, 2700K would still vaporize the plants.
Rather, it refers to the spectrum. 2700K is redder, but no cooler. Stay with what you've got.

[JosephineRose]

I wasn't referring to heat output, but color temperature. I was wondering if the light spectrum was the culprit.

Your suggestion of actual heat output was something I didn't consider, as I notice some warmth coming off all the lights, and I do have fans on everything. After reading your post, I went and touched the bulbs and see that while all are warm, the T5s are warmer to the touch. I will increase the distance as you suggest.

[imp]

We have the same type shelving! Mine are probably 18 to maybe 20 inches? wide, never really measured them for how deep they are.

Just trying to figure out what works best and also is best cost wise, heat wise and all. It's confusing to me, LOL, but it's been a day today- 2 people working upstairs and one in the back, lots of noise to go with everything else.

Is it better to buy two fixtures per shelf or one 4 - or 6 - light fixture per shelf?

These ideally will be in my unheated green house. It is a permanent structure to the house, has something like a 14 ceiling, glass paned from about 4 ft high to the header beams and bead board ceiling, cement floor.

[dmforcier]

Originally Posted by imp

We have the same type shelving!

You got the wire shelves too? Likely they are just under 12" deep between the poles. A 4 lamp T8 fixture with reflector (from Lowes) just fits. Anything more than 4 lamps (tubes) would be massive overkill. My starts want to go sideways instead of up because they get so much light.

[BigVanVader]

Imp I bought the 15 dollar T12 ones from Lowes last winter and they worked great. Took 2 lights per shelf. I bough 6 total.