Shop lights?

1lisac,
How often are you changing out your T12s? I'm not sure at what point/frequency I need to change mine out. I've run this set from last season 16 hours/day at least since I sowed seeds in mid-December 2012.

They were new when I started using them last January 2012, for approximately the same 16 hours/day, until mid-March 2012.

I bought a case for $12 on sale at HD.

Jan + Feb + half of March ~= 45 days
45 days x 16 hours = 720 hours

720 x 2 seasons = 1,440 hours

Since the "lifetime" is usually around 20,000 hours for T-12s, but 15,000 hours might be a better time to change bulbs, according to this arithmetic, you might get to as many as 21-28 seasons out of one tube!

That seemed much too long. The rule of thumb that I hear is "around 2 years, if used 18 hours per day all year"
18 x 365 = 6,570 hours = 2.3 to 3 years. OK, 45 days are just far fewer than 365.

What does your new case say for bulb lifetime? Does it give a brightness curve, or something like "lumens when new, and lumens after 10,000 hours?

I replace mine every other season. Half one year and half the next. I honestly can not see any difference in my electric bill and all the seedlings grow at the same rate, so I don't see any difference there.

Ok. Thanks for the calculation, Rick!

Thanks for the confirmation Lisa. I'm kinda on the same schedule, and seeing the same thing in my bill. When the seedlings start lagging is my clue for a change out.

I using 2 T12 bulbs and a heat mat at the moment to germinate and start my tomatoes. In 6 weeks they will be ready to go in the garden, unless something has changed in the last 6 yrs.

Which varieties are you starting now, Lisa?

I have about 70 different types. I'm too lazy to list them. But I'm doing it the same way I do every year except a little later and only 1 tray this time.

Oh, ok, Lisa.

I need to send some seedlings to Hotlanta, GA around the 1st weekend in April. Something that will survive their temps at that time, and be close to transplanting. I believe they're about a month or two behind me for transplanting tomatoes, but have a much shorter season for tomatoes. So, I'm trying to put together some early, patio varieties to send.

For this season I started out with my old T12 shop light that one of the bulbs won't work & a little 24" grow light. I was able to add a new T8 to the one shelf and you would not believe the increase in light. Since then I added another 3 T8 lights, and the seedlings are doing great. Some of the tomato stems are real fat and the plants look super healthy, some of my best yet. For just under $60 I bought 4 T8 fixtures at Lowe's, and bought a 10-pack of bulbs for $34 for the Phillips brand, which I just happent to like better than the Sylvania's. This week it looks like I'm going to pick up another pair of lights for the bottom shelf, and use the last of the bulbs.

These are the last bulbs & fixtures I plan on buying for a long time. Initial outlay is about 50% more for the T5 lights, plus I already have trouble keeping the room cool with the T8's, so if the 5's put off more heat, I'd be using air conditioning to keep the temp in check.

To me the bottom line is this, I've got new lights, the plants are doing very well, and I could afford the investment, I'm happy with the results. Yes, the T5's might be a bit more efficient & brighter, but I don't think I'll realize much advantage versus expenditure.

My warm room STAYS warm, year round. Something with the way the ducts were routed, and that's not getting changed anytime soon. So, I work with the advantage and germinate the seedlings in there. The warmth helps. Any added heat from hot lights would be problematic in that room.

Once mine germinate, I can leave them in the warm room until the true leaves come on, then move them over to another room that stays cool, year round (another duct issue -- not gonna change!)

LOL!

I think I'm gonna work with the T12s until they phase out the bulbs!

The newer light fixtures that everybody calls "shoplights" are already set up to use T8 bulbs. But get this - The end pins on both T8 and T12 are both the same size which make most of them interchangable depending on the fixture. The manufacturers don't really recommend using T12's because the ballasts are slightly different and may burn out sooner if T12 bulbs are used. The T8's are a lot more effecient, last longer, and are better suited to the newer shoplight fixtures. The stores have recently lowered the cost a bit on T8's, so it makes good sense to consider them when updating equipment. Bulbs come in several color temps also.

They also have T5 fixtures out but they are still very expensive, and perhaps not all that practical for gardening use.

Al

Lyco- NOW I understand. I bought some new 2 bulb fixtures that came with T8 bulbs. I always just buy what's cheapest or what I find. I never looked at the strength of the bulbs if they fit I used them. Now I know why I have 8s and 12s. I honestly can't say I notice much difference but I keep them really close to the plants and the lights do throw off some heat.

Thanks everyone for the wealth of information on T12, T8 and T5 fixtures. BTW - great techy article Rick. Thanks also to those all who provided comparisons between T12 and T8. I hear that T12's are being phased out over time. I'm not sure how long the bulbs or new fixtures will be available. I guess at some point, T12 owners will want to stock up on bulbs.

As of Valentine's Day, I now have a small T5. I wouldn't have ordered it myself, but hey -- I won't look the gift light in the ballast! The T5 went up over the weekend. So far I am NOT seeing a major difference in heat - only about 1 degree. I'll try to do an experiment comparing my new T5 with my "old reliable" T8s and let y'all know how it goes.

My DripWorks irrigation system arrived yesterday. Still reviewing the instructions for setup...

Enjoy! I'm still experimenting.

If you're curious about some kind of jet or sprinkle fixture but didn't want to buy a whole bagfull, let me know. I might have bought five and have little use for 3-4 of them.

But mine are based on mainline plus 1/4" tubing, not T-Tape.

Why do you people want to mess with all those fittings & emitters. You will have problems to no end. Meanwhile, I will be irrigating my 5 acres with T-Tape.

Partly, I like fiddling.

Partly, no two square yards in my little yard are similar. Most beds are tiny and separated. Some of my "irrigation" covers a shifting array of pots, planters, trays and cells.

Few things in life or gardening are "one size fits all".

But I have heard many people with acres and acres, or multiple 100' rows, praise T-Tape for its simplicity and convenience.

I've never grown vegetables under shop lights but for years I put my wifes potted plants in my old store building under shop lights. They did great under them. I build her a green house a few years ago so don't do that any more.

I started seedlings under a shop light. I have not set them out, but they seem okay. Try to put the seeds close to the light to prevent legginess, also do not put too many seedlings under too small a light (my mistake :)

have a look here - handy hints ! http://www.ledhorticulture.com/