Are wordwiz and yucatan the same person?

No. Are you and igrowindoors the same person? You certainly have the same attitude, though he is a bit smarter than you. You probably copied and pasted the pictures you pasted in this thread from someone else and took the credit.

Good day sir.

Rob,

Hey, I'll check back. I just started using a 125-panel LED light for tomatoes, I'm really curious to see how they do compared to a 400 watt HPS system.

I really do have an ulterior motive here - I want to raise at least 56 and perhaps as many as 150 plant(s) indoors this coming fall and then during the winter. The rooms are already heated, so that is one cost I do not have to worry about. If that works, then the following year, at least 400 plant(s) per cycle, with three cycles per year. 1200 plant(s) @ 30 pounds per plant @ $1.25 per pound...

Mike

struw,

You exemplify the way a former boss tolerated and survived people who obviously were incompetent:

Give them enough rope and they will hang themselves.

I'm sure that calling people names and trying to insult them does not change facts, one being that ICDs are inefficient growing lights and the other being they contribute to a greater internode length.

Mike

Are you and igrowindoors the same person? You certainly have the same attitude, though he is a bit smarter than you. You probably copied and pasted the pictures you pasted in this thread from someone else and took the credit.

No. Maybe. No, you are fabricating lies.

Good day sir.

Another lie.

@yucatan
"I can't believe the moderators have not booted you yet!"

Previous posts have been deleted and I think it has been warned as it toned down for a short while. Another complaint may be all it takes. I'm tired of seeing the insults and insinuations. Please email me from my member page.

@Yucatan, here's a pic of one of my grow rooms. It fruits plants with 12- 4' (HO)T-5's in a 5'x5' area. If you get a total of 6-8 (HO)T-5's, that should be sufficient. Do you have reflective material around your plants to conserve light? That is very important, especially growing with fluorescents.

{{gwi:1023437}}

{{gwi:1023438}}

{{gwi:1023440}}

@taz6122, thank you for your concern. I'm glad to know the moderators are paying attention to this type of behavior.

Thanks urbangardenfarmer, that was very helpful. Unfortunately, I really don't have space for an actual grow room in my apartment. Taping mylar to the wall would just look tacky, but you're right... I have to think of a way to incorporate reflective material.

I have five plants growing on a table in my living room under a 2-bulb HO T5 unit. Before I started this post, I was thinking about getting another one of these units, or perhaps a couple CFL's that I could place at the stem level of each plant. But you're saying 6 HO T5's minimum is needed to provide enough light for 5 fruiting plants, correct?

From what I see, your plants look very lush and dense. I'm happy to know that HO T5's can produce such results. Do you have any problem with the light not being able to penetrate the top canopy of leaves at the lamps current distance from the plant tops? How do you like gardening via hydroponics? Also, do those strings hold support/train your plants? What did you tie them to? I use bamboo sticks.

Robert

Mike,

I found some info about what you were suggesting. It's actually called DLI (daily light integral). Mols are simply the units of measurement that are used to attain DLI.

http://www.onhort.com/Daily-Light-Integral-Defined-article7534

Robert,

Yep, just like measuring rainfall per day! It's an iron-clad rule about how many mols per day plan-ts need to prosper.

Mike

Mike,

Another article says, "Depending on season, location, and cloud cover, daily light integral outdoors in the U.S. can range between 1 and 70 moles/day. Daily light integral in the northern U.S. averages around 6 moles/day during November to January, and above 26 moles/day in mid-summer. Light level reaching plants inside a greenhouse can vary between 35% and 75% outdoor light levels."

They show conversion rates:

0.00071 (Sunlight)
0.00054 (MH)
0.00047 (HPS)

So...

2000 footcandles x 0.00054 x 16 hours/day = 17.3 moles/day from MH bulbs.

4000 footcandles x 0.00071 x 12 hours/day = 34.1 moles/day from sunlight.

However, I'm using a 2-bulb, 4-ft. HO-T5 and they didn't provide a conversion rate on how to calculate the moles/day for these lights. I have no way of knowing how many moles/day my plants are receiving.

Can you assist?

Thanks,

Robert

Robert,

A cool white fluro has a conversion factor of .000524. If you know the lux you can figure out the footcandles. I'll guess they are suppose to produce 10,000 lumens. If they are a foot above the can-opy you would get:

10,000 divided by 10.76 (to determine FC) 929 footcandles. At 16 hours per day of light, that would equal less than 8 mols/day.

Increase the lux to 20,000 and you get about 15.5 mols/day.

At 30,000 - 23.

I know, I sound like an economic stimulus proponent, but I really recommend a light meter. I bought one a couple of years ago and it was worth every penny. I tried some tomatoes in a cab-inet a couple years ago using CFL bulbs and had hundreds of blossoms but maybe a dozen of them turned to fruit. Lack of light.

Mike

That's very helpful. So I'm getting 7.789 moles/day for every 16 hours of light.

Now, would it be wise to increase the light to 18 hours to have 8.76 moles/day? Would it hurt to decrease the light to 12 hours/day to have 5.84 moles/day? I heard that decreasing light to 12 hours is beneficial for plants in the flowering/fruiting stage but this is completely contradictory to receiving more moles/day.

I also remember reading a study which proved that providing 24 hours of light/day had no noticeable advantages when compared to 18 hours light/day. What is the rationale behind that if it's true that the more moles/day, the better?

Where can I find a durable, affordable light meter? I'm assuming that it doesn't take an instant reading and that it probably needs to be placed under the light for a couple minutes to gauge a rough approximate light reading.

In an effort to provide you with some insight, I read a few online articles written by the same people of your book recommendation, Paul and Eric Runkle today. They said CFL's work better when combined with Incandescents because CFL's alone have a poor range in the red spectrum. By combining CFL's with Incandescents (50/50), you'll come very closely to mimicing the red spectrum of the sun and have better results with flowering plants.

Regards,

Robert

Robert,

If you really want good production you will need at least 18 mols per day. But, there is more to it than the number of hours of light provided. Tomatoes and peppers need at least four hours of darkness per day. It simply is not as simple as increasing the amount of time the lights are on!

You can buy a decent light meter for about $35. It does take an instant reading.

The article you refer to regarding CFL and ICD was for obligate long-day pla-nts. Tomatoes and peppers are day neutral.

Mike

So there's no benefit to reducing light to 12 hours/day during the fruiting stage? Have you read anything like this in your findings?

Not at all. Think about nature! During summer, when everything in the gar-den is producing fruit, we have 15 hours or so hours of light.

Think of it this way: they will need a DLI of X amount, just as they need X amount of rain. And if you are married and have had a pregnant wife, you know she needs more fo-od, water and vitamins than when she does when she is not trying to grow a "seed." Basically, that's what tomatoes, peppers and everything else you are growing are trying to do - produce seeds. The better the conditions (light, water, temps, ferts) the more seeds they can produce.

Mike

That partly makes sense. But what about when light outdoors is about 8-10 hours a day? I thought summer sun (long hours) was good for green, lush leafy foilage and spring time (shorter hours) was good for flowers.

Different plants have different requirements. Flowers bloom at all times of the year. Same is true for fruit and veggies. It all depends on the individual.

Robert,

Again, think of sex, if you will. If two humans six years old have sex, they more than likely will not produce a baby. But aphids can have babies two days (some say the same day) they are born. As Taz says, it depends on what you are raising. Things like tomatoes have to be 50+ days old after being set in the garden to produce fruit.

You really need to understand the habits/needs/growth cycle of whatever you are raising. Some love bright sunlight and warm temps, others will suffer under the same conditions. Some care about how many hours of light a day they get, others don't, at least as far as blooming is concerned.

Google can be a great friend, but you have to use it!

YMMV,

MIke

Mike,

I have used Google, read many books, as well as consulted two of my indoor gardening friends. One grows dwarf citrus trees, the other grows more questionable plants. I get different advice from each of them, especially about lighting. The questionable friend is absolutely convinced that his "plants" are healthiest at 16 hours HO-T5 light/day during vegetative and 12 hours HPS red spectrum light/day during flowering. It's hard to argue with his method after having seen his yields. My other friend has about 3 lemons and limes at any given time on his plant. I want more yield than that. Does this matter as to whether they're long-day, short-day, or day neutral? Please explain.

I taught myself a lot. But I guess I just expected the more I taught myself before I actually did it, the less problems I would encounter. My research did help, but there's no such thing as doing something like a pro the first time simply by listening to other people's experiences or by reading instructions, no matter how detailed the instructions are. If that was true, we could all fly a fighter jet flawlessly the first time.

I will continue to experiment and learn, but you're saying I should run my HO-T5 18 hours/day for indoor chiles and tomatoes, regardless of the plant's life cycle? The thing I still don't understand is if they're both day-neutral, then it shouldn't matter how much light they get a day as long as it's over 12 hours. It is my understanding that day-neutral plants will thrive whether if grown in the same way as long-day or short-day plants.

http://everybodysgardencenter.com/april/growlights.asp

Q: How many Hours should I keep my Lights on in my garden?

A: This depends on what you are growing. For flowering plants that include Roses, Tomatoes etc. 16-18 hours of light and 6 hours of darkness are needed daily for vegetative growth, and 12 hours of light combined with 12 hours of COMPLETE darkness for the fruiting and flowering phase.

Robert,

They NEED 20 mols per day - that can come over 8 or 18 hours, makes no difference!

No way do tomtoes have to have 12 hours of complete darkness to fruit or flower. As I posted in another place, ever munch on a ripe mater from the vine in July? Look at the sunrise/sunset times.

Mike

Mike,

I want to make it clear that I'm not arguing with you and I actually value your input. It's just that I'm finding mixed evidence. So far your advice is the only source that suggests a consistent 18 hours of light. Maybe the other sources are speaking specifically for HID lights since they supply more MOLS/day than HO-FLUOROS in the same timeframe.

http://www.hydroponic-gardening.ws/grow-light-science.html

We can use blue spectrum 6500K lighting with our Hydroponic plants to create more vegetative growth in the beginning plant stages. Blue light run for about 16-18 hours would recreate the Season of spring and the production of leaves and branches.

We can then change our Hydroponic lighting to the red spectrum of 3000K for a shorter period of about 12 hours to recreate the Season of Summer. This will induce flowering and fruiting of the Hydroponic plants.

Robert

Robert,

Actually, 16 hours is just what most people use - it can be 10, 12, 18, 20, even 24 (for a while). I think it's based on the DLI from shop lights so to get to 14-16 mols/day for seedlings, people run them 16-18 hours. I have a 400-watt HPS, plus a 125-watt LED and they run about 15 hours a day. I'm getting a lot of blooms on my toms including some a foot from the canopy top.

Mike

Hey yucatan, I think I know where you mixed answers are coming from. There's two different thought processes on indoor growing, especially when your talking hydroponics. You have the people who grow marijuana and everyone else. The unwritten rule when growing weed is 18/6 vegatative and 12/12 flowering. I'm not saying that's the only plant that needs those hours, but that's what comes to mind when it's mentioned. Like Mike said, tomatoes, peppers and almost everything else doesn't work that way. Go with Mike's advise on the moles per day. It's over my head, but I'm pretty sure he know's what he's talking about.

Thanks urban. That makes sense because a lot of marijuana data comes up when you type info on plant lighting in google. I never doubted Mike, but I wanted more proof. I value his input and yours.

Regards,

Robert

Found this from a very reliable source:

"With higher levels of blue light and lower levels of red light plants start to produce more compact leaves and also produce other pigments which absorb light without transferring it for photosynthesis. These effects may be desirable in ornamental plants but reduce yields in leafy crop plants.

A common misconception is that the ideal color of light for plant growth is sunlight. Much of the light spectrum of sunlight is actually wasted by plants."

http://www.terraponicshop.com/grow-lights.html

Robert,

Any person with access to a keyboard and web space can say anything, it doesn't mean it is true. Yes, plan-ts do not use all of the spectrum of light the sun delivers - it is a multipurpose body! But reality is growing things have adapted to sunlight.

Check out this page about light spectrum and how to see it at ho-me. The white LEDs look interesting!

Mike

Mike,

Did you visit the link I provided after the quote? They explain in detail as to why they make those assertions. It isn't just opinions, unlike most of the advice I have read.

Even the link you provided said that a big portion of blue light from natural sunlight is wasted in the atmosphere.

Robert,

Yes, I did. A fact: they claim summer days are shorter? Huh? Shorter than what? The longest day of the year (as far as sunlight goes) is the first day of summer/last day of spring. I know, I am preaching to the choir, but the sunrise/sunset times do not equal out until the first day of fall. And I can grow plan ts using the same amount of light per day the entire year. And it is true that some of the blue spectrum is filtered, but plan-ts' ability to absorb blue light is much higher than its ability to absorb red light. That's why most LED panels have far mo-re red bulbs than blue.

Another false statement: HPS and MH bulbs are primarily used for growing much taller plan ts and they have to be placed several feet (emphasis mine) above these big plan ts to prevent burning.

Hogwash. My 400 watt HPS is about a foot, maybe less, from the canopy. I can hold my hand a foot under it and it barely feels the heat.

I'm just telling you what I know and have studied. I really don't care if you believe, adapt, use, promote it or not. I play with lots of types of lights: shop lights, fluros, HPS, LED, CFL and post results. I rely on experts to provide data that tells me how much lighting I need and pass this on. Seriously, I don't have a horse running in your derby! But I am willing to compete with anyone in a one-on-one test. We both grow the same variety of plan t, the challenger using whatever lights he/she wants and I'll use the sun. We can compare cost to produce per pound!

Mike

Hey yucatan, that's a very informative website. I am kinda unclear on the narrow spectrum theory. I googled it and couldn't find much. Are they saying a narrow spectrum is using blue and red bulbs or a specific color spectrum like 5,000k? This is probably a stupid question. Sometimes I over read things:~)

Mike,

No they didn't. They said Fall days become shorter hence the 12/12 light schedule with more red spectrum for fruiting plants. Plants absorb more blue/red depending on the stage in their lives. Plant hormones trigger fruiting and at this stage they rely on more red light/far red light than blue light.

HPS/MH bulbs are usually placed within 2 to 3 feet from plant tops. Hence several feet. They are capable of penetrating the canopy more than fluroescents hence their ability to grow taller, denser plants. You must have an old unit, or maybe a weakened bulb. This information can be found online almost anywhere.

I'm not concerned with proving you wrong, I'm concerned with having factual data with evidence, not ideas based on opinions and personal experiences.

@urban: I'm assuming they mean that HO-fluorescents provide a very narrow spectrum, which can be mistaken as incomplete by some people, but actually is optimal in exactly the ranges it needs to be, e.g. 420 nm and 630 nm.

Robert,

If by old you mean more than two months, I'm guilty. Like I said, I really don't care! But I have to wonder - personal experiences using different lights doesn't count? What can I say?

Mike

Mike,

But you just said, "I rely on experts to provide data that tells me how much lighting I need"

... well I provided expert data.

Robert,

While much of their information may be correct, I wouldn't consider a seller to be a reliable source of information. The first two sentences you quoted, for example, were simply copied from a post here on GardenWeb back in '06. Most sellers simply copy and paste their information from various sources.

The big advantage of red light is that, due to its longer wavelength, it takes less energy to produce. On a watt per watt basis, light at the red peak (~660nm) has 50% more photons than light at the blue peak (~440nm). Since photosynthesis is driven by photons, not watts, red light results in 50% more photosynthesis per watt than blue light. This is important to you since your primary concerns are high yields and minimal energy input. Keep in mind though, that the red spike of your fluorescent bulbs occurs at ~610nm, not the 660nm peak of photosynthetic activity. While the blue spike perfectly matches the photosynthetic peak of 440nm. That may negate the previously described advantage of red light. I don't know if you'll see much advantage in substituting more red light for blue.

Also, I see no advantage in changing light spectrum or duration for day neutral plants like tomatoes. They will bloom whenever they are mature enough to do so. For many people this is during the longest days of the year.

Most sellers don't provide information about lights. It seems that the info on the website is legit and what's more likely is that it ended up on a forum.

There is also a study that I recently read (dont have the patience to search for it now) done by researchers at a university that showed that just because the figures in the graphs peak at a certain number (660 nm in your example) doesn't mean that it's the best utilized nm by plants. There are many variables to account for than simply glancing at a peak on a chart.

As far as your last sentence, I'm still not convinced either way and have yet to see solid, concrete proof that the theory works for all fruiting plants. Most people swear by it, but the very select few, including yourself, say it doesn't matter. Just know that I am not discounting your advice on the matter.

It seems that the info on the website is legit and what's more likely is that it ended up on a forum.

A domain name search shows that the website was created in 2007, and the post was made in 2006. There is nothing to indicate their credibility and everything to indicate that they simply copied and pasted relevant information from unknown sources. Much of the information may be good, but who knows how much? Or which parts?

As far as your last sentence, I'm still not convinced either way and have yet to see solid, concrete proof that the theory works for all fruiting plants.

Not all fruiting plants, just day neutral plants. That is, in fact, the definition of day neutral; plants for which flowering is unrelated to photoperiod. People in warmer climates, or those with greenhouses, prove this all the time by growing huge crops of tomatoes in June, the longest days of the year.

There are a lot of widespread myths in horticulture. Hobbyists get a little tidbit of science and extrapolate it way too far to form false statements. Just because something is repeated often does not make it true.

1) It's possible that the company was created before the website was launched. It seems rather well written so I doubt it was compiled from several sources.

2) There is nothing to indicate credibility of user opinion on a forum either.

3) Unless proven in a replicable empiracle experiment by a Doctor, Horticulturist, University Professor or the like, I don't think any advice on planting can be taken completely at face value.

4) There's much bias out there and the source I provided didn't seem like one of them. After researching on other seller websites, mostly hydroponics, they all break down lighting for the customer without promoting any of their products. An educated consumer is a happy consumer. The terraponicshop website supported the claims they made regarding HO-T5's, which is more than I have found from most people who give advice based on personal, but limited and un-measurable experiences.

If the website didn't exist in 2006, then how could shrubs n bulbs here at GardenWeb have copied it? There is extraordinary evidence to suggest that the website owner copied at least some of his information, but if you choose to believe otherwise, so be it. It really doesn't matter.

My point is that you should be looking at scientific principles of plant growth, not unreferenced information at vendor websites. Photoperiodism in plants is a well understood scientific principle. Long and short day plants require certain photoperiods to bloom, while day neutral plants do not. If you're growing day neutral plants like tomatoes and cucumbers, there's no need for shorter days. And you don't have to believe me, just read up on photoperiodism. But you'd do best to stick to scholarly sources like universities, rather than vendor and hobbyist sites.

" I'm concerned with having factual data with evidence, not ideas based on opinions and personal experiences "

Maybe you should just email back and forth with struw instead of posting on GW. Most of us are Hobbyists not Scientists and most of them just follow the grants. Just like politicians, I don't believe most of what they say. My personal experiences are much more reliable IMO than what someone is paid to say. Evidence is often manufactured.

penfold2: What specific copy and paste job are you referring to? That thread is filled with posts and it's difficult to find what you're referencing.

In response to scientific principles of plant growth related to High-Output Fluorescents and their capacity to fruit day-neutral plants indoors to maturity without ever seeing the sun, please post a scientific source which replicates just that, or at least presents a guideline. In all my research, I haven't found anything at all that is relevant to that type of gardening which doesn't center on HID lighting. The link I provided was the closest source to explaining some (but not all) of the details associated with HO-T5 lights that I was interested in.

PS - I never said shorter days are required, I said they "may" benefit tomatoes at the flowering stage. The evidence for either viewpoint isn't too substantial. Despite being day-neutral plants, why are we told by "experts" to treat tomatoes like long-day plants (18/6), and is this dependant on the life stage of the plant? Find me hardcore evidence and you'll have something to support your opinion.

Robert

@taz: I've seen many back-and-forth convo's on GW which sound very scientific and in-depth, so much so that a new gardener would likely get lost in the conversation. Just visit the container gardening section and you'll see what I mean. My point is that just because we are discussing indoor lighting, doesn't mean we're more scientific than other's who recommend specific nutrient ratios and soil mixtures for a very scientific reason. I'm not looking for people who are paid to say something. I'm looking for quantifiable evidence as to why something works rather than the uncertain opinion's of people, most of which have never grown fruiting plants from start to finish using strictly HO-T5's.

Yes, a forum will most likely have high opinion and bias, but I found that GW members are slightly more intellectual than that. I just haven't found someone with all the answers on lighting as of yet. And struw is a jerk, as I'm sure you know from referencing his name.

" I just haven't found someone with all the answers on lighting as of yet "

And you won't but you have found the most informative people on this subject right here in this thread. The problem is that you're not listening.

" Just visit the container gardening section and you'll see what I mean "

You can try to point out a forum on GW I haven't visited but I doubt you will have any success.

struw is a jerk
yuca is a fool.

What specific copy and paste job are you referring to?

I'm referring to this bit posted by shrubs n bulbs about 1/3 of the way down:

With higher levels of blue light than the 5%-10% used in these experiments, plants start to produce more compact leaves and also produce other pigments which absorb light without transferring it for photosynthesis. These effects may be desirable in ornamental plants (and medicinal plants) but simply reduce yield in leafy crop plants.

Aside from a small substitution at the beginning, it is copied word for word. It just illustrates the point that people can get information from anywhere. It's not really useful unless it comes from a trusted source.

I never said shorter days are required, I said they "may" benefit tomatoes at the flowering stage. The evidence for either viewpoint isn't too substantial. Despite being day-neutral plants, why are we told by "experts" to treat tomatoes like long-day plants (18/6), and is this dependant on the life stage of the plant?

There is no scientific evidence to suggest that day neutral plants benefit from short days at the flowering stage, so I'd say the burden of proof is on anyone who disagrees. And I have seen no proof. As for why "experts" tell us otherwise, I think the quotation marks say it all. These people are no experts. Have they studied plant biology (from reputable sources like universities, textbooks, journals, etc)? Have they done experiments with multiple controls? In most cases, no. They are simply repeating anecdotal evidence. This is why our hobby is so riddled with misinformation. I'm not saying that I'm an expert. Just that I know enough to know when to look elsewhere for information.

I mean no insult, but it sounds like you may not realize just how much misinformation is present in this hobby. When statements get repeated often enough, people begin to accept them as fact. Then these things make their way into manufacturer literature because manufacturers would rather cater to misinformed people than lose money trying to reeducate them. Here is a perfect example:

The uselessness of high P fertilizers

So stick to reputable sources and don't believe something just because the "experts" say it's so. And please note that I do try to keep an open mind. If there is good evidence for something, I will always consider it.

Yucatan,

Methinks you do not seek advice, but rather substantiation of your intentions. You ask about fruiting with fluorescents but you ignore that 630 nm light from the sun is the same as 630 nm light from a fluro, CFL, HPS, LED or HPS. The "evidence" that tomatoes and peppers are day-neutral is everywhere, including in nature. People who make a living (or corporations who make millions of dollars) growing veggies in a greenhouse would not spend mega-bucks on lighting if they only need 12 hours a day. Yes, tomatoes can produce just as many blooms and set as many fruits with 12 hours of lights - as long as the light intensity is equal to 4000 footcandles or so for those 12 hours. But if you want to learn more about what causes flowering, Google florigen and antiflorigen.

Not meaning to preach, but you ask for advice and several people have provided it. It's not that you question it - that would be great - but you discount it or say it is not relevant because it doesn't deal with T5-HO lights.

Good luck with your endeavors.

Mike

@taz6122: Of course I'm listening. First you say that I shouldn't be here asking all of these questions so scientifically and intellectually because you're mostly hobbyists. Then you say I have found some of the most informative people on the subject right here in this thread, yet you are unable to provide more than opinion or support for your claims. I am well aware that tomatoes and chiles are day-neutral plants. I'm not asking for proof for these facts. Please re-read my actual concerns as I'm not interested in writing them for the 10th time.

@struw: Just stay out of this. I told you once before that I don't need your advice. You're a very rude and obnoxious person.

@penfold2: I could care less about the source of the information, though I am quite certain that the original claim was from terraponics. They have a plethora of valid information on that site and it encompassed more about HO-T5's than the advice I have received here thus far. Company websites for small businesses are usually not launched within the same year as the actual business.

There is no scientific evidence to suggest that day neutral plants benefit from "long" days during the "flowering" stage either. One of my concerns pertains to just that - Find me concrete evidence that proves a higher ratio of red/far-red light is beneficial, detrimental or completely meaningless during the flowering stage.

I think most people would have an affinity towards information produced by from reputable sources like universities, textbooks, journals as opposed to a forum poster simply because they do test the results empirically and support it with evidence and multiple controls. If you don't believe in the validity of science, where do you get information for topics such as these? Personal opinion and limited experience?

@wordwhiz: Part of the reason I may be coming off angry is that I simply don't understand the science behind these High-Output T5 fluorescents since there is little to no studies which encompass their effectiveness and relationship of nm to plants for optimal results. Please don't categorize me as some naive person who will believe anything that is said on the topic. I have read a lot about this topic and only about 2% of it is relevant. If I sound excited for a link I posted, it's because that information was more informative than 98% of the material that I have come across thus far.

Of course 630 nm is the same wavelength for each light source. But different sources emit different intensities and different mixtures of the 400-750 nm spectrum. The effectiveness of a bulb is not only about having it peak out at a 630 nm; there are many other factors to take into consideration. I'm not discounting anything. I'm just slightly wary about taking the information at face value with no evidence to support the claims.

I make a lot of demands because I want to learn the right way the first time. I don't want to be riddled with misinformation that costs me money and time. Despite what you may think, I believe that 18-22 hours of artificial light per day (more red than blue) will benefit day-neutral plants best regardless of their life cycle. That is my personal belief and I have absolutely no support for it. But recently, I have heard about using a higher red spectrum with a reduced light period during the flowering stage and this intrigued me as well as confused me. I want to know the most optimal course to take and why.

Regards,

Rob

You're making this more complex than it needs to be.

You've seen a photosynthetic action spectrum and know which wavelengths are most efficient for photosynthesis. Use bulbs that provide plenty of efficient red light and enough blue light for proper growth form.

You've been given DLI values for the plants you grow. Figure out how many hours you need for the bulbs you're using and stick with that number year round for day neutral plants.

And don't worry about the differences between T5's and other light sources. Plants have accessory pigments that allow them to make use of a wide range of wavelengths. That's why the photosynthetic action spectrum is so broad. All you need is more bulbs.

There will always be people making incorrect generalizations and even completely false statements. This is the internet. Once you see some good results, you'll learn to ignore them.

@penfold2: You're absolutely right. I am making it more complex than it needs to be because of all the conflicting advice. Sorry if I have ticked you off in any way. I tend to agree with everything the last post you submitted.

Have a Happy Holidays,

Rob

It's frustrating to see so much conflicting advice on the internet, but all you can do is learn to sort through it.

Hope you see the results you're looking for.