Rick, I thought I covered it, but maybe I got sidetracked in another post. Anyway, here goes. We were talking about forcing dormancy(downard trending) and reducing moisture, temperature and light and CO2 was an uncontrolled constant value. When shortening the light (daytime) period, my practice is to always cut the daytime period short at the end of that particular day. My thinking is that this gives the plant plenty enough nightime period to complete it's functions of utilizing all of the food and energy it has made and stored that 'last long day' as well as maybe do some self cleansing of occluded or trapped unused CO2 and other impurities. The start up time for the next daytime period remains the same to start the new daytime-nightime schedule of decreased light hours. If I were to lengthen a light (daytime) period, such as with seedlings growing bigger (upward trending), I would add light to the beginning of the first longer day allowing the plants more time to produce food and energy to begin that new regiman. I'm not talking about light-dark reactions of the Calvin-Benson cycle--only daytime/nightime periods.

I remember you saying you thought it shouldn't make a difference what end light was removed or added, and it most probably doesn't. But that's how and why I do it--if nothing else, for consistency. Della mentioned adding supplimental light in the morning, then natural light during the day with more supplimental light at the end of the day. I don't think I like that idea. I would add it all in the morning only and then at some point in the future go to all supplimental lighting.

Thanks, Lorn. This was one of those things you thought would bore everyone, so you said you would tree mail me, but got side tracked. I totally understand the "I don't know if it really matters, but just in case, I'll do it this way" thinking. It is the naturally the safe way, and I endorse it wholly. But I haven't changed my stance (of indifference), as none of those reactions are dependent on the dark to my knowledge. Although I do agree, that some do work more efficiently in the dark, given other factors that coincidentally occur at night. So.... maybe you're right(!?)

Della, sorry to temporarily hijack the thread, but at least we came up with the same answer from two different perspectives:
--- If it makes a difference, we would choose to add light in the pre-morning rather than the post-evening.

Rick, that Light that Della was looking at on Ebay has a very narrow 6000-6500k wavelength zone--white light zone. It is not a full spectrum light, much less, not a grow light with full spectrum and elevated zones of red and blue. In the description it even says it's "a suitable replacement for traditional light source suitable for home, office or exibition lighting" The fact the listor called a grow light is a MISTAKE! Unless, of course, it might have some use with deep water aquatic culture; maybe with deep water coral (?).

The fact that why anyone would even want to use this assembly combination (a stripe of LED's in a fluorescent tubing) is a paradox to me. Seems to me one would be defeating the efficiency purpose of LED. As you know, most of the efficiency gained by LED is because their angle of projected light is much narrower, allowing a more focussed beam to land on a given surface as opposed to fluorescent tubes which radiate light in all directions, wasting much of what is produced. So, why then, would anyone want to defuse LED by putting it in a frosted tube and lose whatever they thought they were gaining. Beats me! But yet you can buy these here too, even at Walmart.

Thanks for that, Lorn. And no, I didn't know that that was a major reason contributing to LED efficiency.

I supposed the LED marketer assumed that since a grow light was also rated at 6500K, they must be the same.

I have to say, it can be confusing to a regular person...

It can be confusing, Rick, and fustrating too because there are so many ways to measure light and each gives a different numerical value as a result. Fortunately, there are conversion tables for one to another, etc. I don't have any practical user experience with LED, having never used them for plants or seedlings, but one of the disadvantages I can imagine would be the distance above the leaves would be quite fussy and less forgiving than a fluorescent along with a lot of sharp shadows. Actually, I think we've got it pretty good with the flexibility of the current T5's, T8's, etc. with a triple phosphor system that gives a full daylight spectrum, a good red zone and a good blue zone. I think they're pretty forgiving in terms of distance vs. intensity at the leaf canopy.

I just finished watching the movie "Grumpy Old Men" (again). Had to get away from lilies for a couple hours. I see Wabasha still had the welcome sign up last summer: "Welcome" "Home Of Grumpy Old Men" . Great show--Nice town.

Oh wow.... I'm one confused 'regular' person. But getting there, I hope ! I assumed that something marketed as a grow light... would be a grow light!

Thanks for all the patient explanations.

Can I just clear up... is it possible for one tube to be manufactured to emit peaks of both the red and blue spectrum? I notice your fixture, Lorn, has two tubes, and in another ebay setup I saw it contained two tubes, one of 4000k and another of 6500k. I'm confused if it takes one or two tubes to do the job. *ashamedly ignorant*

Extra light at the morning end of things is best, got that. No confusion there

Oh sure--Those are the ones we call 'grow lights'. They contain: 1. the full daylight spectrum, 2. elevated red zone at about 3000k, 3. elevated blue zone at about 5000k. Most grow lights utilize a tri, (meaning 3) phosphor system to achieve that. The human eye cannot readily detect this extra red and. blue when a full spectrum of light is incorperated; although if one knows it's present, you'll will be able to detect it a little. LED grow lights, on the other hand, are generally very wavelength specific, so most of those you'll see appear (Edit) only red and blue. Edit; this should read: red or blue or some combination of both, red and blue diodes.

Now, you mention you saw a double tube set up that has a 4000k tube as well. That's interesting because I was going to talk about that earlier, but backed off from it because I felt it would just add more confusion because in photobiology, we first have to learn the most phosyhthetically active regions (PAR) of plants are the regions of red and blue wavelengths. So we sort of concentrated on red and blue for a while. But there is another zone: the 'green zone'. It lies right between the reds and blues at about 4000k. It is sometimes called 'moonlight'. Many people use it as a nightime period lightsource on plants. Many people believe there may be a whole lot more going on with plant functions at night than we currently realize and that green light is benificial to those functions. But I don't have any green tubes and I don't use any type of nightime period lighting. It's and interesting area to me tho, and I'm still learning more about it's use every day. So far it's only made in as a single zone, separate tube as far as I know. The current grow lights don't have that elevated green zone but do have some green.

My double tube setup I have that you mentioned---I only use doubles when I need a broader spread at the same intensity such as when I have two or three rows of pots or baggies, etc.

Roosterlorn said:LED grow lights, on the other hand, are generally very wavelength specific, so most of those you'll see appear only red and blue.

A critical typo that should read "red or blue".

So we now understand that reputable brand grow lights have good amounts of both read and blue light. It's all in the specifications of the product.

Especially in the early days when the real grow lights were very very expensive, many would use (together) one warm light florescent tube to emit the red spectrum, and one cool white florescent tube to emit the blue light. In fact I still have a four lamp fixture with this set up. However, I think this is less efficient, energy wise, in regard to plant usable light, than using half as many grow lights that emit both blue and red light simultaneously.

I tend to read wiki pages with a skeptical eye, but the wiki color temperature page has a good, easy to read table.
http://en.wikipedia.org/wiki/C...

That's good reading. Except sometimes I think those photography boys live in a 'light' world of their own--they lose me. You know what's fustrating? Remember when we used to buy a fluorescent grow light, most often there would be a glossy white page within the box with a beautifull full color chart printed on it? Not any more! And, here just the other day when I opened some pdf's on Sylvania, GE, Philips,etc. under the links for specs, charts and graphs to post here, not a single one had a color chart. Most were so generic, more suitable for elementary school reading. One of the links drew a blank page with a prompt on the bottom: "back to the top".

But now, on these same company websites, there is quite a bit of information on LED, including charts and graphs and so on. Maybe they're presenting an 'eye to the future' which I think is good. And maybe now is the time for us to get in on the 'ground floor' of LED, knowledge wise.

Roosterlorn said: And maybe now is the time for us to get in on the 'ground floor' of LED, knowledge wise.

Yes.And then it's always fun to reminisce with the younger folk, too, about "I remember when...."
There's getting fewer and fewer people out there who know what a teletype is/was.

So is it time to buy shares in LED lights?

The colour temperature chart is very good. I've seen a breakdown of the spectrum now on ordinary flourescent tubes in the supermarket, but the brands of grow light you have in the US don't seem immediately applicable here.

Unless I go into a 'grow' shop and ask? But the only customers they generally get are the pot growers :D I'm not exactly lazy, but I like to find things online and take alot of time to research and understand them, rather than have a salesman desperate to make a dollar hovering at my elbow telling me what I want. I buy terrible things under pressure >.<

Della, I think the best approach for you to take right now is to buy a complete fluorescent Gro Light setup that has a HO T5 tube included. HO means 'high output'. It will save you a whole lot of confusion and fustration for now. A single bulb unit tipically costs about $70.00 (AU and US) which might sound like a lot but it's far less than an LED setup would cost. If you are going to be getting into seeding, consider it a long term investment. I am positive you'll never regret it. Sand is running thru the hour glass on your project and it would provide you with something you can use right now. Then, as time goes on, you'll have plenty of time to learn more about the principles of lighting and applications, specs and what not. That's how I approached it. I paid full price for my first unit. Then as time went on, I picked up another and a couple extra tubes at a 'out of business' sale, found another like new at a rummage sale for $15.00, and still another 2 footer new in the box at another rummage sale for $6.00. All HydroFarm units like in the picture I posted earlier. Here's some product information:

HydroFarm
www.hydrofarm.com
Product Code # JSV4
54 watts-120V-60Hz-0.85A ( USA )
5000 initial Lumens
T5 tube rated at 20,000 hour life

It's hard for me to shop Australian souces from here in the States to see who's got what, but HydroFarm has a distributor in New Zeeland. They are available within the UK and you might also see them under the name HydroGarden. But it doesn't matter who's brand it is so long as you get a set up similar to what I recommend.
It is a 4 ft unit. the 'Jumpstart' growlight system in the JSV4 box and includes everything you need to be up and running in 5 minutes or less (except a timer).

Had to add this for kicks: potatos growing in the space station under LED's. Looks like pinklight.

Space spuds :D

I searched ebay for the HydroFarm jumpstart when you first posted it and only found a US supplier: http://www.ebay.com.au/itm/Hyd...

But if it's really the best way to go, I'll just have to bite the bullet and find a local grow shop that sells something similar to what you've spec'd, without a frame. :D

Thanks again. For some reason this seems like quite a mammoth step. Then I think - it's also something that could be used to start seeds early. I'd love to shorten the bloom-time wait in hybridising. A greenhouse would serve the same purpose I guess, but I'm renting here, and not able to build such infrastructure.

Punch in 'Jumpstart Grow light'. You'll see a lot more. Ebay prices are high; local retailers, upscale garden centers and the like are much more reasonable--like $69.00 regular price. We've got at least one unit occupied around here all the time. When I'm not using them for lilies, we use them for African Violets or starting veggy and flower seeds or cuttings--many different uses. Right now my little grandaughter even borrowed one of my units to start her flower seeds at her place.

Ok... so much trawling around trying to make a decision on this has finally revealed light!

You've been giving me great information, but I was just drawing a blank with retailers on and off line here. At last a really helpful lady in a speciality lighting store explained - Aust. is in the dark ages of fluoro technology. We can't get T5 gro lux tubes here at all yet. They have only just started bringing in T5 black light and insect repellent (orange) tubes. So, I could source a T5 batten, but no proper grow light tubes.

Online, 'cool light' and 'day light' flourescent T5 tubes are being sold as grow lights, but the spectrum breakdown isn't optimal like that of gro lux. One brand calls itself "grow lush", and I think others are just everyday lighting being sort of off-label marketed. Sellers are promoting the value of their lights' green and blue spectra as somehow perfect for hydro growing. Red spectrum just being pushed for 'flowering'. ie. budding. Reality is... almost no one uses lights here unless it's for hooch.

At one hydro shop the guy wanted to sell me this http://www.philips.com.au/c/en... for $85 with no more explanation than it was "what everyone is moving to" and "it's so much better than the old fluoros", while completely ignoring the dusty T8 tubes on the bottom shelf. I had to ask, and then he knew next to nothing about them.... (which is marginally more than I really know :D).

So, T8 Gro lux tubes and battens are available, but much more expensive than some of the other set ups being hawked. (Due to the cost of a plug-inable batten or cost of an electrician to hardwire one!) I decided that if I couldn't get the T5 set up, as I aim to, then I could only afford to spend a minimal amount on a stop gap measure to experiment with. It's all a grand experiment anyway.

So... short version is that I ended up ordering this: http://www.ebay.com.au/itm/200... The only quick, cheap solution with a reasonable peak around 620nm. (Quick - after all my months of analysis paralysis and procrastinating!! Ha!!)



I needed the batten, but not a reflector, as I plan on making the whole inner surface of the glass door reflective. (I can tape on aluminium foil, right? Right? )

And egads... it's felt like winter today.

That would work too. It has all the proper wavelengths we're taliking about. 130 watts will give off more heat, of course, so you'd have to keep an eye on distance. A little extra heat might be a good thing now that it's getting colder, too. Your project is a very interesting to me.

It arrived today! The light!



It was packaged really well for transit. The bulb is bigger than I imagined it would be! But the fitting is designed to be suspended down. I need a horizontally placed light here, so I just strung it out inelegantly between some wire in my enthusiasm to get it ready for testing out tonight/morning.

I also whitewashed the inside of the lid, at the behest of someone that knows better than me. I was determined to leave the glass clear because I wanted to see the seedlings through the door, but I'm often away for two-three days at a time, and I didn't want babies to die of overheating if some freak hot sunny spell hit. I also imagined opening the lid on days I'm here - even though there is good ventilation in the box, I still think of 'fresh air' as best!

Hmm.. so, where was I? I was talked out putting foil on the ceiling as both solution to overheating and light-reflector, as this would have required fancy (as yet non-existent?) remotely controlled robotic arm to open up box for daylight/breathing every day I wouldn't be home

Anyone have experience on how well whitewash allows good photosynthetic light to enter glass houses? My more knowledgable friend assures me that with lid closed enough light diffuses through to enable good growth. (I trust their knowledge - I just have no experience in this area.)

So... by this evening when the fading light defeated me, the project looked like this:



Thanks for your encouragement, Lorn.

Pretty neat so far! It seems a shame to be wasting a lot of the emitted light from the top of the bulb. Maybe in time a idea will come along as to how you can direct the unused light more out and downward. Maybe the whitewash will reflect/defuse a lot of it back down though, we'll see. You know if you think about it, the only real light you're utilizing is only that small portion that strikes the leaf--the rest is wasted. And that's true no matter what kind of set up you have, whether it's a T5 like mine or any other. You'll have to keep a close eye on temperature until you gain some experience with your setup because this is a pretty high wattage bulb. I've found that in general, cooler conditions with lots of light produced the best bulb growth.

I don't have any experience with whitewash. I would go with all the natural light I could get, but stick with your friends advise for now because he's familiar with whitewash and I'm not.

I think your are going to be pleasantly surprized at how well this is going to work.

They commonly use a whitewash on glass greenhouses, to reduce the heating by the sun. I have no experience with it either, but I think it is a good idea. Just glass itself is UV light blocker to some degree. Not only do I think whitewashing is a good idea, I think your neighbors will think so, too. I can just imagine that powerful light, beaming from the "box", and your neighbors wondering if E.T. is visiting!
But I think I would still place some tinfoil inside the door directly above the light. You will capture a lot of light that would otherwise be lost.

I don't know about a remotely controlled robot arm, but methods for automatically opening and closing greenhouse vents have been on the market for 50 years, and I'm sure backyard inventors have been doing it for way longer.

Sounds like you're all revved up with the project, and you should be!