Lights for starting from seed.

[Hotwired]

Actually the Par curve from that Post is one I created based on Chlorophylla, Chlorophyllb, and Cartenoids. The one used for the CFL comparison is Phillips Lighting's interpretation of PAR Curve that they sent me when I was having a disagreement with the engineer over specs. This is the actual curve that relates to the what we think of as PAR. Usually the curve is averaged and doesn't show all the bumps and spikes. Sorry the CFL overlay is not actually correct relative to the actual PAR curve. As far as Green Light, the plants use very little of it, and the reason you see green is that it is reflected instead of absorbed.

And Colin... very good info, you seem to be very up on optics. I see you're from Oklahoma. I designed and sold a bunch of coupon dispensing kiosks with 3D Real-Image floating advertisements. They installed them in Groceries all over Oklahoma. I guess the guys made more money scamming their investors and creditors than selling ads.

[Doug9345]

Originally Posted by Billydove

Thank you "Hotwired" for pointing out I was looking at the wrong bulbs. I am also enjoying the link to your setup. Extremly informative!!!

Thank you as well "Doug9345". Tractorsupply site is currently down for maintence however I look forward to seeing what fixture you use. Would you mind telling me which CFL bulbs you get from Wallyworld as I do not see any 6500K Daylight CFL Bulbs on their site.

Thank you

I too want to say thanks Hotwire. The reason I said I might not replace the 2700K bulbs has to with having flowers in the winter. I just realized they don't show but that petunia plant has been flowering profusely for 3 weeks now and it is also a supplement to window light. You know how little sun we get in the winter. Most of my tomatoes start inside and end up under plastic or glass outside.

I just got back from our local Walmart. The General Electric Daylight CFLs are $11.88 for four. You really have to look them over to find the 6500K marking. It's an arrow on a line on the back. The Great Value, their house brand was $9.00

[davidstcldfl]

I'd also like to say, 'thank you' to Hotwired for all the info...

I just bought 3, four foot shop lights and GE daylight bulbs. My tomato starts will be happy when I get them set up tomorrow..
Our weather in central Fl has been changing back and forth so much, I think they'll do better inside, for awhile.

[sio2rocks]

Originally Posted by Doug9345

I too want to say thanks Hotwire. The reason I said I might not replace the 2700K bulbs has to with having flowers in the winter. I just realized they don't show but that petunia plant has been flowering profusely for 3 weeks now and it is also a supplement to window light. You know how little sun we get in the winter. Most of my tomatoes start inside and end up under plastic or glass outside.

I just got back from our local Walmart. The General Electric Daylight CFLs are $11.88 for four. You really have to look them over to find the 6500K marking. It's an arrow on a line on the back. The Great Value, their house brand was $9.00

I have a flat of periwinkles under some 6500k fluorescents that I have been raising since they were little plugs. They are now around four inches tall and wide and are all starting to flower significantly. I don't really see any difference between mine and the ones at work in a greenhouse under sunlight other than mine are about 2 weeks ahead of theirs' growth wise (theirs' have just started to bud up mine have been for about a week now). So I think the 6500k work well for flowering in typical plants as well as being the best for vegetative growth.

Colin

[sio2rocks]

Originally Posted by davidstcldfl

I'd also like to say, 'thank you' to Hotwired for all the info...

I just bought 3, four foot shop lights and GE daylight bulbs. My tomato starts will be happy when I get them set up tomorrow..
Our weather in central Fl has been changing back and forth so much, I think they'll do better inside, for awhile.

I was doing some calculations last night and found that even though it might seem more efficient to buy point source light and reflectors to raise plants (CFLs and worklight reflectors) it actually is less expensive to buy fluorescent light strips and tubes. I figured this out because even though you focus as much as 30% more light on plants than the tubes the area is different and you require more bulbs and fixtures. Plus the price for CFL bulbs of higher lumen output (1000-1600 lumens -still below the 2500-3000 per bulb of cheap tubes) is cost prohibitive if you have to have several more than the tubes. Most of the cost is in the CFLs too so when they burn out they are more costly to replace than a tube fluorescent. I was really thinking about changing some of my setup out for CFLs but after some intense spreadsheet work found it is not worth the effort or money.

[davidstcldfl]

Originally Posted by sio2rocks

I was doing some calculations last night and found that even though it might seem more efficient to buy point source light and reflectors to raise plants (CFLs and worklight reflectors) it actually is less expensive to buy fluorescent light strips and tubes. I figured this out because even though you focus as much as 30% more light on plants than the tubes the area is different and you require more bulbs and fixtures. Plus the price for CFL bulbs of higher lumen output (1000-1600 lumens -still below the 2500-3000 per bulb of cheap tubes) is cost prohibitive if you have to have several more than the tubes. Most of the cost is in the CFLs too so when they burn out they are more costly to replace than a tube fluorescent. I was really thinking about changing some of my setup out for CFLs but after some intense spreadsheet work found it is not worth the effort or money.

In my earlier post, I wrote...GE daylight bulbs. I should of wrote...GE daylight fluorescent tubes.
I agree with you sio2rocks. Thats why I went with tube fluorescents.
The only thought that I did ponder was...the 4 foot lights will 'only' be used to start plants. Since I'm in Fl, that should be at least twice a year.
If I'd gone with CFL bulbs, I could use them in most of my house lighting, as needed.

[davidstcldfl]

Originally Posted by sio2rocks

I was doing some calculations last night and found that even though it might seem more efficient to buy point source light and reflectors to raise plants (CFLs and worklight reflectors) it actually is less expensive to buy fluorescent light strips and tubes. I figured this out because even though you focus as much as 30% more light on plants than the tubes the area is different and you require more bulbs and fixtures. Plus the price for CFL bulbs of higher lumen output (1000-1600 lumens -still below the 2500-3000 per bulb of cheap tubes) is cost prohibitive if you have to have several more than the tubes. Most of the cost is in the CFLs too so when they burn out they are more costly to replace than a tube fluorescent. I was really thinking about changing some of my setup out for CFLs but after some intense spreadsheet work found it is not worth the effort or money.

In my earlier post, I wrote...GE daylight bulbs. I should of wrote...GE daylight fluorescent tubes.
I agree with you sio2rocks. Thats why I went with tube fluorescents.
The only thought that I did ponder was...the 4 foot lights will 'only' be used to start plants. Since I'm in Fl, that should be at least twice a year.
If I'd gone with CFL bulbs, I could use them in most of my house lighting, as needed.

[Cole_Robbie]

Originally Posted by sio2rocks

I was doing some calculations last night and found that even though it might seem more efficient to buy point source light and reflectors to raise plants (CFLs and worklight reflectors) it actually is less expensive to buy fluorescent light strips and tubes. I figured this out because even though you focus as much as 30% more light on plants than the tubes the area is different and you require more bulbs and fixtures. Plus the price for CFL bulbs of higher lumen output (1000-1600 lumens -still below the 2500-3000 per bulb of cheap tubes) is cost prohibitive if you have to have several more than the tubes. Most of the cost is in the CFLs too so when they burn out they are more costly to replace than a tube fluorescent. I was really thinking about changing some of my setup out for CFLs but after some intense spreadsheet work found it is not worth the effort or money.

These two parts together, plus one easily scavenged cord, make an awful cheap light. I use the "cool white" version of the bulb:

http://menards.com/main/lighting-cei...671-c-6337.htm

http://menards.com/main/lighting-cei...055-c-6384.htm

If you want to be extra fancy, you can use a shelf bracket and scrap of wood to hang the light so that the bulb is horizontal, and place an aluminum pan above the bulb as a reflector.

On a $ per lumens basis, I would be surprised if that setup can be beat.

[Hotwired]

Originally Posted by sio2rocks

I was really thinking about changing some of my setup out for CFLs but after some intense spreadsheet work found it is not worth the effort or money.

If you really want to waste some money, then invest in LED tubes for fluorescent fixtures. I just did a comparison of 5 brands relative to PAR, and "they're bright in all the wrong places". Almost sounds like a song title. I just did a post on it.

[Got Worms?]

Seems to me that, as the initial cost of the lights (w/fixture) go up, the cost of running them goes down and vice versa. At least for fluorescent and LEDs. I run the most efficient lights that I can afford (and no more) that will do the job so I can save a little on each end. Everyone has their own needs and priorities.

[ChrisK]

Exactly. Carotenoids can capture a little of the energy Chlorophyll cannot. Photosynthesis is only ~15-20% in the green portion of the spectrum, if memory serves. Thanks for the clarification on the strange PAR curve.

Originally Posted by Hotwired

As far as Green Light, the plants use very little of it, and the reason you see green is that it is reflected instead of absorbed.

[artis]

Originally Posted by Hotwired

If you really want to waste some money, then invest in LED tubes for fluorescent fixtures. I just did a comparison of 5 brands relative to PAR, and "they're bright in all the wrong places". Almost sounds like a song title. I just did a post on it.

Hotwired,

Sorry to intrude here but there is something very wrong with the graph that you provided. Warm white LEDs are actually quite good at matching the PAR action spectrum. For a reference, I am attaching PAR action spectrum from Inada's original research, #14 is tomato.

[Hotwired]

Originally Posted by artis

Hotwired,

Sorry to intrude here but there is something very wrong with the graph that you provided. Warm white LEDs are actually quite good at matching the PAR action spectrum. For a reference, I am attaching PAR action spectrum from Inada's original research, #14 is tomato.

Can you send me the link for the PAR curves. This is not a curve that I've ever seen. As I said, I'm an optical engineer and not a botanist. Are these photosynthesis saturation curves in Watts per square meter, and at what stage of growth. The saturation curves for foliage growth is much different than for flowering. I was aware that each plant species has it's own PAR and the "Accepted Par Curve" is a composite or averaged curve. I'm trying to expand my understanding of PAR, so I'd like to see your link to the Inada study. I've seen a study by AA Tikhomirov that I'm still trying to digest. I can design optical coatings to manipulate light to do most anything, but plant biology is still a bit like Greek to me, but I'm trying to learn more.

[RayR]

Originally Posted by sio2rocks

I have a flat of periwinkles under some 6500k fluorescents that I have been raising since they were little plugs. They are now around four inches tall and wide and are all starting to flower significantly. I don't really see any difference between mine and the ones at work in a greenhouse under sunlight other than mine are about 2 weeks ahead of theirs' growth wise (theirs' have just started to bud up mine have been for about a week now). So I think the 6500k work well for flowering in typical plants as well as being the best for vegetative growth.

Colin

Same here Colin. I have Sparaxis that have bloomed this winter under GE Daylight 6500K 4ft. tubes, Alpine Strawberry plants continue to bloom as well.
I have a Spicy Globe and three Fino Verde basil plants that I also overwintered indoors under the lights that continue to bloom, even collected good viable seed from the Spicy Globe so far.

[dice]

I have a question: what is the process that reduces the efficiency
of flourescent lighting over time? What causes flourescent bulbs
to lose output per watt of input over time? (I know other kinds
of lighting lose more or less efficiency over a given length of time
of operation than flourescents, usually more, but I am wondering
how the output of flourescents degrades with use.)