Why spend $$$ on a flowering lamp if you have a $ veg lamp?

churchhaze

Well-Known Member
Really? If your aim is to achieve the fastest possible vegetative growth - which it was - then using a constant light source meant the only variable was photoperiod. Which was the whole point of the exercise.
You're confusing 2 people. I never said that was my aim nor was that reason included in any of my points.
 

churchhaze

Well-Known Member
Really? If your aim is to achieve the fastest possible vegetative growth - which it was - then using a constant light source meant the only variable was photoperiod. Which was the whole point of the exercise.

If you adjust your light source, then how do you know what is responsible for faster or slower growth? Is it the photoperiod? Is it more intensity? Is it less intensity? Is it the type of light? Is it the colour shift from dimming? Is ist the spread from raising or lowering the lamp? Is it the increase or decrease in ambient temperature?

How do you address all those variables?

It's all good and well for the armchair experts, but what have you actually done to prove your own theory?
So no, you haven't tested this while keeping DLI constant. Thank you for your answer. So your evidence is pretty much useless.

In the future, instead of keeping your overly powerful veg lamp on for a shorter time, make a smaller veg lamp for less money. Get the same DLI.
 
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Prawn Connery

Well-Known Member
You're confusing 2 people. I never said that was my aim nor was that reason included in any of my points.
That was my aim.

I think, honestly, you are getting a little too defensive now. We both know my evidence is not "useless" - for reasons already explained. The point being, I've actually done it. What have you done?
 

churchhaze

Well-Known Member
That was my aim.

I think, honestly, you are getting a little too defensive now. We both know my evidence is not "useless" - for reasons already explained. The point being, I've actually done it. What have you done?
How was it a useful experiment? You discovered that 24h provides similar or worse results than 18h and concluded it was because of the length of day, didn't even consider that reducing DLI could have had that effect. For all you know, the DLI was too much at 24h and was just right at 18h.
 

Prawn Connery

Well-Known Member
I think you're having a bit of trouble reading what I wrote, because that's not what I did at all.

In any case, I'm still waiting on your evidence. Perhaps I need to wait a bit longer.
 

churchhaze

Well-Known Member
I think you're having a bit of trouble reading what I wrote, because that's not what I did at all.

In any case, I'm still waiting on your evidence. Perhaps I need to wait a bit longer.
You're the one that showed up here claiming that 18 hours is better than 24 hours. Why should I be the one providing evidence? You failed to make your point. I've never seen conclusive evidence on this before. DLI is never taken into consideration.

I gave you a few theoretical reasons for 24h being better and you gave me the same reasoning behind why you need a dark period I've been hearing for almost 20 years now with an experiment that doesn't provide conclusive results.
 

Prawn Connery

Well-Known Member
No, I'm the one who showed up here to debate your argument about spending money on a veg light before spending it on a flowering light.

My opinion hasn't changed. I haven't seen much basis for most of your assertions. If you were to provide some evidence, perhaps I could be swayed. But it does not appear to be forthcoming.

In any case, this is a bit of a pointless argument. I've already said what I needed to say.
 

wietefras

Well-Known Member
In absolute sense the flowering light clearly saves you the most money and that's the lowest hanging fruit to spend your time on first.

The VEG light is only used for 3 weeks while the flowering light is used for 10 weeks. So the savings per grow for your example it comes down to:
Veg savings: 1344Wh for 21 days=28kWh.
Flower savings: 2160Wh for 70 days=151kWh.

Besides no one should ever have been using CFL lights for growing plants. It's just by far the worst you can use. Replacing more efficient tubes means you save only 17kWh per grow.

I did replace my veg light by led strips too, but in my case I save €147 per m2 per year on the flowering light and €15 per year (per flowering m2) on the veg light.

So it makes sense people don't feel the urge to go replace their veg light for only a few bucks in much of a hurry, but saving hundreds on the flowering lights makes much more sense to spend a few weekends on.

Also, it can get rather nippy in the veg room with leds only. So I see people install a heater to keep the temps up. Then the savings of switching to leds are really more like zero.
 

churchhaze

Well-Known Member
The VEG light is only used for 3 weeks while the flowering light is used for 10 weeks. So the savings per grow for your example it comes down to:
Veg savings: 1344Wh for 21 days=28kWh.
Flower savings: 2160Wh for 70 days=151kWh.
It's a given that both the veg lamp and the flowering lamp are on every day. The veg lamp's size already takes into consideration the different needs of veg and flowering.

The veg lamp is the low hanging fruit because it's MUCH easier to stomach the initial cost. Most people aren't interested in making such a large up front investment for a flowering lamp, and for good reason. (The reason is that HPS will do a great job for much less up front cost)


Besides no one should ever have been using CFL lights for growing plants. It's just by far the worst you can use.
This is also a given.

Missing the point. I'm specifically wondering about those people with crappy veg lamps.

Maybe I should have named this thread "Why are you using shitty veg lamps?", because most people aren't picking up the nuance in the question.
 
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churchhaze

Well-Known Member
€15 per year (per flowering m2) on the veg light.
You obviously did it so you see 15 euro a year as worthwhile. You like saving money. It also cost a lot more up front for your flowering light investment. More reward at the cost of more up front money and risk. (there's a risk you don't use it until the cost is amortized by the energy savings)
 
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churchhaze

Well-Known Member
If your pockets are deep enough to replace your HPS with LED, it's probably within your budget to upgrade veg at the same time. If it's not, you shouldn't be thinking about replacing HPS with LED in the first place unless it's just a fun hobby.where you don't really care about the financial aspect.
 
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churchhaze

Well-Known Member
Also, it can get rather nippy in the veg room with leds only. So I see people install a heater to keep the temps up. Then the savings of switching to leds are really more like zero.
The same argument can be made for flowering with a more efficient lamp in colder climates. Why not just use HPS.
 

churchhaze

Well-Known Member
I understand that with smaller operations there are sometimes bubbles in veg where you don't need the light on. The same thing can be said about flowering.

Sometimes you have plants in veg while flowering is down, waiting for clones. Flowering light is off until it has clones under it.

Edit: Of course bubbles in the veg pipeline and turning the light out implies losing your phenos/mothers, while a bubble in flowering pipeline means a few days/weeks of lost flowering time. Poor planning or unforeseen problems in vegging is usually/always the reason for bubbles in flowering pipeline in the first place though. It's assumed that if you don't want to lose your mothers, veg is always on, even if it causes you to produce more cuttings than needed..
 
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SPLFreak808

Well-Known Member
Easy: flowering light

Replacing a 400W HPS with either a 600W HPS or 400W of LED should - all things being equal - result in about a 50% increase in yield (as long as you have the space).

So there you go - I've just paid for my new light with enough left over to buy a new veg light, too.

In almost every case, upgrading your flowering light - if it is sub-optimal to begin with - will result in an increase in yield. That buys a lot of electricity. It will also likely improve your smoking experience and save you time in trimming, by growing denser, higher quality flowers with less popcorn to trim around.

What does upgrading your veg light do? Seriously. You are going to flower at the same stage of growth. Getting a better veg light may get you to that stage quicker and save a couple of $ in power. It may reduce stretch, giving you a bit more head height. But if you run a perpetual cycle indoors, you have at least six weeks to veg in-between cycles (eight weeks flower less two weeks to clone or raise seeds), which is plenty of time to get to the required stage of growth with modest veg lighting.

A better veg light is not going to improve your flowering yields. Unless, as some here have mentioned, you plan to grow outside. Or use the same light to veg and flower.

But if you're using the sun to flower, or one light to veg and flower, then we're not even having the same conversation, are we? You only have one light, so there is no choice as to which to upgrade first. I don't even know why these questions were asked, hence why I didn't answer them above. It's obvious.

Without sounding like a broken record, I just don't follow the OP's logic. A better flowering light will always give you better yields, which is money in the bank to upgrade your veg light. You wouldn't put the cart before the horse, would you?

And again, I am not arguing there are not efficiencies to be gained in upgrading your veg light. I'm simply arguing there is a logical (fiscal) order in which to do it.

As for CFL's, they have their place. I'm using one to supplement UV and vertical light in a staggered grow. It was cheap - $28 or something - and LED doesn't have much UV to speak of. The buds in these photos were harvested this week and were so big when they finished that they broke quite a few branches:
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Nice plant, and for the most part id always swap my flowering light first except for the condition i posted above. With total draw remaining the same, I would rather take a 50% par increase in veg rather than a 20% increase in flower but, only if i was stuck in a situation exactly like that.
 

churchhaze

Well-Known Member
Okay, to clarify, when I said $ and $$$, i'm talking about quality, or price per watt of initial cost to buy the lamp, not the total price of the lamp.

In other words, a 600W HPS and a 1000W HPS are both $$. Making it bigger is not what I mean by $$$.

You guys are talking about expanding in general. Yes, expanding in general will make more flowers regardless of whether you buy decent LEDs or more HPS.
 

WeedSexWeightsShakes

Well-Known Member
If your pockets are deep enough to replace your HPS with LED, it's probably within your budget to upgrade veg at the same time. If it's not, you shouldn't be thinking about replacing HPS with LED in the first place unless it's just a fun hobby.where you don't really care about the financial aspect.
If you can’t afford decent lights in general you are not doing very well in life lol

@Prawn Connery do you notice much a difference in 18/6 vs 20/4?
Btw the example you provided is perfect. Why wouldn’t you use your same lights lol? I currently have been running 24hr cause it’s cold as fuck where I live and also had to put a small heater in there.
 

Prawn Connery

Well-Known Member
Hey mate, yeah there's a small difference between 18/6 and 20/4 in terms or rate of growth. I also run my veg lights quite soft, at about 35%, so I'm getting reasonable efficiency out of them (5000K F strips).

The main difference for me is that because I run a perpetual cycle, I actually have more time to veg than I need. Clones take less than two weeks to strike, and then I'm left with six-seven weeks to veg when I really only need three. Often I clone, veg, and then clone again before I finally flower. I don't keep mother plants, because it's easier to clone from successive generations.

I also keep cuttings in the fridge. The longest I've kept cuttings in the fridge and successfully cloned them is six weeks, but one month is usually pretty safe.

So I'm actually trying to slow growth down in my veg set-up. I also have heat to deal with in summer, so the six-hour break in the middle of the day is a good respite for the plants, and also means I don't have to water them twice a day. I hand-water in veg - which also slows them down a little compared to auto-water in flower.

In winter I'll usually be on 20/4 and in summer 18/6. The warmer it is, the faster the plants grow, so the different seasonal cycles balance themselves out.

One thing I have discovered is that I built some 4000K veg lights for a friend - exactly the same as my LED frame, but 4000K instead of 5000K F series strips - and the extra red appears to have accelerated growth for the same strains without any stretching issues whatsoever.

At first, this seemed counter-intuitive - old skool growers veg under MH and flower under HPS - but the extra red in the spectrum actually speeds up growth, as plants can photosynthesis it more efficiently than other spectra. LEDs already have a lot of blue in them, so IMO the shift to red from blue-green by going to a lower kelvin temperature or possibly higher CRI appears to be beneficial. My conclusion is that 4000K CRI80 is actually a better flowering spectrum than 5000K CRI80.

Hope that helps.
 

Prawn Connery

Well-Known Member
Nice plant, and for the most part id always swap my flowering light first except for the condition i posted above. With total draw remaining the same, I would rather take a 50% par increase in veg rather than a 20% increase in flower but, only if i was stuck in a situation exactly like that.
I don't know your set-up, but I do know how most people grow, and their veg times are easily half or less than their flowering times. So speeding up vegetative growth is generally not a priority.

For example, I can't even fathom this statement:
Sometimes you have plants in veg while flowering is down, waiting for clones. Flowering light is off until it has clones under it.
I never have an empty flowering chamber. I often have to prune my plants in veg or reclone them to fit in with my flowering schedules.

Power savings are power savings - there's no doubt, and certainly no argument on my part.

But veg lights are usually a fraction of flowering lights - easily a ratio of 1:4 or less - so even if you are running them 24/0 compared to 12/12, and even taking into account the efficiencies of a crappy CFL vs HPS, you're almost always ahead in terms of power savings if you upgrade your flowering lights.

Plus the obvious advantage is flowering lights produce bigger buds - veg lights don't. But I'm kinda tired of repeating that! :bigjoint: People who have been growing indoors for any length of time know exactly what I'm saying.
 

WeedSexWeightsShakes

Well-Known Member
I do a similar perpetual style.
Since it’s cold right now clones and veg plants are taking longer and growing slower.
I usually do 18/6 as well but since it’s been so cold I have them 24/0 but thinking of switching to 20/4 since I have a small heater in there now.
Veg is around 300watts and flower is 1600watts
 
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