Hi all, sorry about this question but I'm really wondering if I already have shop lights I would hate to go out and buy more. ( it has something to do with vegetables because I need to put my seedlings under them asap.) By the way one of them is a lamp the other one is a long ine screwed onto a work bench.
Fluorescent lights vary in what wavelengths they produce. Old light are very low light compared to what plants need, though they seem bright enough to our eyes. Our eyes see yellows and greens the best. Plants use certain wavelengths in the red and certain wavelengths in the blue areas of the spectrum. Most 'shop' lights will be rich in the wavelengths that we see best.
If you are going to move the seedlings out pretty much as soon as they sprout, then you are probably fine even with old lights. You really just need the light to see what you are doing, the plants won't be there long enough for it to be a problem.
But if you want to grow them on, get a bit bigger before transplanting them to the garden I would look into new bulbs.
If you can find some with a K value of about 6,500K, or that are labeled 'daylight' that will be better than old bulbs.
If you want to grow the plants even longer, then I would put in some money to get good reflectors and special bulbs that produce the right wavelengths for the plants. Do some research about the PAR rating system for light.
If you replace the bulbs (a good idea every 2 years if you run them 18 hours every day), one "cool" bulb and one warm" bulb is an alternative to two "daylight" bulbs. They may be cheaper than "daylight" bulbs. Also, maybe but not certainly, more efficient.
If you do get around to buying new fixtures some day, either T-8 or T-5 fixtures are MUCH more efficient than old "T-12" bulbs. T-8 bulbs draw less power but as bright or a little brighter than the old T-12 bulbs.
T-5 bulbs typically draw more power, but they can be as much as twice as bright as old T-12s. And they are m ore expensive, but not twice as expensive, you they are cheaper per lumen.
Lumen measure the brightness. Watts measure how much electrical power they draw. The new T-8 and newer T-5 bulbs give more lumens per Watt than the old T-12 bulbs.
T-5 bulbs are still being improved. There are T-5s made that more more efficient, OR brighter, OR longer-lived. But prices are still higher per bulb (not always higher per lumen).
I was wondering about the distance, since my cucumber seedlings seem to be dry (not the true leaves) just the very tips I was afraid they might have too close. I guess they are not..these are the cool lights.
Thank you, first garden :). I planted Green arrow shell peas and provider snap bush beans yesterday.. who knew getting the soil ready was so much work! I feel like I worked out yesterday.. very rewarding tho
I agree that you don't want to water something that's rotting.
Maybe you can wick some of the water out of the soil by setting the pots or cells on top of paper toweling on top of a terrycloth towel, old cotton socks or a Tee shirt. When you get the water out, air can enter in, and probably the roots need air.
When they are ready for more water, consider watering with dilute hydrogen peroxide. That should help a little at knocking down molds and fungus. Also, it carries a little oxygen into the soil and releases it where the roots need it.
maybe 0.2% ... dilute the 3% stuff you find in drugstores 16:1: like 3 tsp of peroxide per cup of water, or 2 ounces per quart.
Others have used it much stronger without killing seeds. Maybe it is safe to use it stronger on roots: yours do sound pretty sick.
Don't be upset about a setback! You've already achieved the first level of gardening success: they aren't ALL dead! I can remember (it was quite recent) when every seed in three big trays failed to emerge. And every seed in two big tubs (except for one species that came up months later) never emerged. Over-watering and waterlogged soil.
Did you say "first garden"? They sprouted AND not all the seedlings died. You're doing really well!
Sharing things like cherry tomatoes and seedlings with neighbors could get them to owing you favors. Grass clippings, coffee grounds, watering plants when you're out of town helping with shoveling, not complaining about compost heaps ...
I usually direct sow cucumbers rather then starting them inside, because they are fast growers. So you may want to supplement your number of plants by direct sowing some, when the weather is right. By doing this you eliminate having to have harden the plants off and there isn't any transplant shock.
I have 2 of the 48" T8 (cool shoplights) on pullies so I can get them close to the seedlings and I've been very happy with them.
This year, I need to grow about 300 plants for a charity sale so I need more lights. DH insists I need to buy T5's instead of T8's because they are more efficient. He bought 1 set so far and they appear to be much hotter than my T8's. I'm afraid that even if I keep them 18" from the plants (distance between rack rows), they may still get burned.
Has anyone noticed a huge difference in the heat output of T5 vs T8? Are there different types of T5 lights that may be cooler?
We have been growing seedlings for 25 years. All we use are cheap shop light fixtures. Run of the mill bulbs. They used to be about a $1 apiece. Probably higher now. The big thing is keep them close to the plants, like no more than 2". We space the shop light fixtures 16" apart.
I transplanted some cucumber and gray squash today, i just dont have the room inside for the big "pots" (milk jugs and two litter pop cut outs) they were dying on me so I thought I'd give them a chance outside.. i did harden them for a few days before.. its gettin warm during the day 70s ill cover them at night and hope for the best :), my peas are sprouting :)
Country Gardens. I have to agree that the shoplights seem to work well. I bought the 2 I have about 5 years ago. I'm not sure how much they were but I remember they were very reasonable. They hold 2 T8 bulbs each and are reflective inside near the bulbs. I'd love to find more just like that but after hours of searching, it doesn't seem like they make those any more.
Thanks for the tip GymGirl. Drthor does have beautiful plants.
The heat could keep the temps too high and give you leggy seedlings. That would be my concern, along with wasting money. Seedlings, once they germinate, are usually grown between 60-70 degrees. Too hot equals leggy seedlings.
I just wanted you to see drthor's plants. Notice how high she keeps those lights away from the plants. I wondered why, until I realize how much heat the lights were generating. And, like 1lisac said, drthor moves her seedlings into a much cooler room to grow on under regular shop lights, after they germinate. She doesn't keep them under those lights for the duration. She only uses the T5s to coax them outta the soil...
With that said, I had considered converting to the T5s, before I know what I know now. I'm sticking with my plain old T12 shop lights for $10/kit from HD/Lowes. I can get replacement bulbs for $1/per at my local Habitat Restore. I use two kits side x side per shelf..To date, I'm up to 8 kits (16 lights). I utilize two shelves in each room.
Since my T12s don't generate that type of heat, I simply move them from my "warm" room to my "cool" room, and grow them on till time to harden off. They love the cool room, where they get to fatten up.
I have just realized that you are talking about me here and ... thanks.
Let me correct this:
"drthor moves her seedlings into a much cooler room to grow on under regular shop lights, after they germinate. She doesn't keep them under those lights for the duration. She only uses the T5s to coax them outta the soil..."
I don't have a cooler room. I have only ONE room.
I start all my seedlings under T5 lights on my upper shelf until they are too tall. At this point I have no choice but to move them down one shelf where I have T8 lights. They grow ok here ... but not as well as under T5.
But no anymore ... I have just updated my second shelf to T5 lights.
Where did I say that drthor moves her plants to a cooler room? Lol Thats what I do. I've learned that from reading seed starting catalogs and from commercial growers like Bernie and Shoe. When people due this for profit there has to be room to make a profit. Lol. I've always been told that I grow beautiful seedlings so I must be doing something right. What's the difference between T 8 and T 12 lights?
Thanks Bee, I guess I'm wondering what regular shop lights are T8 or T12? Thanks for the link. My regular old shop lights have always given me short stock seedlings I guess I never paid that much attention to the bulbs. Lol
Old shop light are T12, that is, 1.5 inches in diameter or "12/8" inch). I thin k they go bacxk to the 1930s and are very inefficient compared to modern CFLs.
T8s are one inch in diameter: eight 1/8ths. They are more modern technology (CFL) and MUCH more efficient. They recently started coming down in price to cost little more thyan T12s.
T5 tubes are 5/8" in diameter. They are the newest technology, and arou8nd as efficient as T8s, on average. Some T5s are much brighter than T8s or T12s. Some are designed to have longer efficient lifetimes, or be extra-efficient over a standard lifetime.
T5s are still so new that they are still evolving (and more expensive.) However, don't be put off by seeing one T5 bulb cost twice as much as a T12 or T8! It is probably twice as bright and/or twice as efficient as a T12.
Both T8s and T5s are supposed to need "electronic" ballasts like other CFLs.
Old T12 fixtures have "magnetic" ballasts.
However, the T8 pis "fit" he old fixtures, and I've read mixed things about whether that's just inefficient, or unsafe, or won't work with some kinds of T8s. One source claimed that the original T8s from Europe would "go either way", but that was just one source.
So I don't truly know about T8s, but I believe it's a bad idea (or very bad idea) to plug them into the wrong kind of fixture.
To get better efficiency than T12s, you have to use modern tubes AND modern fixtures. If you want something a lot brighter than T12s, you need to get T5s.
If you have T12 fixtures, and want something a little brighter, there are SOME modern T12 bulbs that are as bright as T8s - but the bulbs are more expensive e and they are not as efficient as T8s.
T-12 usually emit 2,100 to 2,800 lumens and consume 409 watts. Some pricy ones may put out high as 3200 lumens, or consume as few as 32 watts, but you can pay extra for EITHER brighter OR more efficient, but can't get both in the same T-12 bulb.
T-8 usually put out 2,725 to 3,000 lumens and consume 28-32 watts. And their price is coming down.
New kinds of T-5s keep coming out, many of them more expensive per tube. but they not be much more expensive per lumen.
T5s are about as efficient as T-8s, and you can get 5,000 lumens for 54 watts! Or more efficiency and less brightness. Or longer bulb life.
Bernie, there is a new thread in the Veggie forum that talks about that.
Rick the T5s may be more efficient but I would have to replace so many lights and fixtures that are only used seasonally that there is no way I would ever break even.
Besides the ones I have work fine. I have great seedlings every year. If it's not broke I'm not going to fix it. I have also heard the T5s throw off a lot of heat. After my seeds germinate I try to reduce the temps for shorter, stocker plants. If I have to keep the T5s 18" from the plants it seems to me the extra heat and lite is going elsewhere and that seems wasteful. When the cheap shoplights no longer work I will look for a replacement. But after starting at least 10,000 seeds they seem to be doing their job.
>> Rick the T5s may be more efficient but I would have to replace so many lights and fixtures that are only used seasonally that there is no way I would ever break even.
Yup! One of these decades they will start showing up in Habitat for Humanity stores, and then I'll swoop in!
>> Besides the ones I have work fine.
I suspect that the main benefit of increased brightness would be not needing to adjust lights as often, or keeping some vegetable types indoors longer. Or new fixtures might have only one tube instead of two per shelf, or support a shelf 22" wide instead of 11". Which way do you run your trays?
>> heard the T5s throw off a lot of heat.
I've also heard t6hat from just one person, but if they are more efficient than T-12s, how can they emit more heat? Maybe it is more heat per tube, but meanwhile the tube is putting out twice as much light.
I forget if I siad this 10 posts ago or not, but it bears repeating:
The least expensive way to get more brightness AND more efficiency is to clean your bulbs and reflectors!
Next most expensive is hanging side reflectors so fewer photons escape.
Next most expensive is replacing your bulbs every 2-3 years if you're using it more than 6 months per year.
After around 15,000 hours turned on, a T-12 bulb is so much less bright and less efficient that you'll almost recover the cost of the new bulb in saved electricity costs. Waiting until black spots appear and the bulb actually burns out (20,000 hours) is wasting a lot of electricity and giving your seedlings less brightness than they could have. .
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.
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.
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!)
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.
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.
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 :)