Lighting How Much Light is Optimal, How Much is Too Much, In late Veg. Phase

[BII]

Some questions:

1) How much LED light, such as watts draw per sq. ft., is too much and how much is optimal during late veg. growth, such as days 30 until switch to bloom nutes?

2) Is it OK or best to give as much light as possible, and back off if problems are seen, such as leaves curling/crinkling on more than 1 plant? How do you approach determining how much light to give during late veg. phase?

3) I have 6 plants in AutoPots in a tent doing well, typical size, healthy, etc. now at day 30. For days 1-12 they were under an Amare SS150CR on veg setting (150 watt full draw, guess about 80-90 watts draw on veg. setting?) at 36 inches height. This provided the best early veg. growth I've experienced. From days 13-30 (now), they were under both a California Lightworks SolarStorm 440 (235 watts draw in veg. setting) and the Amare SS150 (80-90 watts draw on veg. setting?) - total of about 320 watts draw - at 36-40 inches above the 'canopy.'. Again, good results. Now at 30 days, I've just added another SolarStorm 440 (235 watts draw in veg. setting) aimed from the side at the plants.
So I am currently running about 555 watts draw covering 6 plants [2 x 235 watts for the SolarStorms + 150 for the Amare] - each light about 36-40 inches/meter above the canopy. Is that too much? Should I simply run like this and decrease light intensity if any problems show up?

4) So far height, growth, node spacing, stretch, etc. are fairly normal/average. At what point does too much light cause inadequate vertical growth? If the plants are going crazy branching and forming buds but not growing much vertically, what are the downsides of growing squat bushes vs. tall plants? So far in prior grows, I get satisfactory yields growing short bushes, e.g., ave. ≥90 g/plant, 2 oz/sq. ft.
Might I get more yield and/or quality if I give less light to at some point, presumably, to induce more stretch, get more height? When, what range of days age, does light need to be limited to induce stretch, and how much would I need to limit light in my setup to induce stretch/vertical growth?

 

[AutoWonders]

Many ways to grow with many opinions. I'm from the school of "let there be light". My led lights run 24/7 (24 hours per day, 7 days per week). Normally I start with full spectrum from the time I plant my germed seeds until harvest time.

Two SolarStorms with 5 watt diodes for 6 plants should do well indeed. You can drop those lights to about 24" from top of plant to light and see how they do. Tweak from there. Next time you can start those lights at 32" or so and drop down over a period of about 2 weeks. You might be getting too much stretching with your current height. Auto's are tough plants, they can endure a lot.

 

[BII]

Many ways to grow with many opinions. I'm from the school of "let there be light". My led lights run 24/7 (24 hours per day, 7 days per week). Normally I start with full spectrum from the time I plant my germed seeds until harvest time.

Two SolarStorms with 5 watt diodes for 6 plants should do well indeed. You can drop those lights to about 24" from top of plant to light and see how they do. Tweak from there. Next time you can start those lights at 32" or so and drop down over a period of about 2 weeks. You might be getting too much stretching with your current height. Auto's are tough plants, they can endure a lot.

Thank you. You confirm my general presumptions that once the plants are weeks old and good size it is best to run as much good light as the setup and the plants can handle; and that at a month old they can handle higher intensities. I had been concerned after reading about too much light stunting vertical growth, which I want, and that only up to half bloom power/intensity levels should be used. Now this seems like good advice for early veg. phase, with seedlings, but I just couldn't find much guidance for what it best in the 28-30 day to bloom phase.

During bloom, I will be running 2 x SolarStorm 440's (640 watts draw) and as side/angled lights 2 x Amare SS150CR's (300 watts draw), 940 watts total draw, in a 12.5 sq. ft. tent., 75.2 watts/sq. ft., with 8 plants (6 in AutoPots, 2 in AirPots). Between power and heat, this is as high wattage/power as I want to go. I have had multiple successful grows using this basic setup (2 SolarStorm 440s plus 2 x about 150 watt draw side lights).

Any comments or suggestions regarding optimal height using higher intensity-type lighting, now including COBs? I see a lot of successful grows having lights either as close or as high as possible in tents. Which is best, such as associated with higher potency and yield?

 

[AutoWonders]

"Any comments or suggestions regarding optimal height using higher intensity-type lighting, now including COBs? I see a lot of successful grows having lights either as close or as high as possible in tents. Which is best, such as associated with higher potency and yield"

My current lights have 4x30 watt COB chips. My current run shows two of my plants are fine with the COB's, the 3rd plant does not like it at all and the leaves were screaming about it. I ended up pinching (use duct tape) the main cola branch to bend it over and give me more headroom. It's a tall, wide plant. With my 5 watt diode led lights, I never try to get them as close as possible. I've no need to, my plants yield well.

 

[Corgy]

there is no such thing as too much artificial light........

https://www.autoflower.org/threads/tina-from-marshydro-live-section.40686/page-225#post-1000910

Just saying..........

 

[BigSm0]

I agree and disagree with a lot said here. First off congrats on picking up an Amare panel. There is such a thing as to much light and not all lights are created equal. Amare panels using Cree diodes are in the 50% efficiency range, other panels using brigelux and epistsr range between 20-40% efficient. So wattage is sort of useless. The Amares output watt for watt is double the cheaper panels. When plants are happy and are getting enough light they aim their tips upward to help capture the most amount of light possible. When there is to much light they usually drop their tips. Also watch for bleaching. I have seen this a lot in my current grow at heights that past strains have loved. The point to this is basically all plants and lights are different so the best thing to do is learn how your current crop handles it.

As for run time I always do 5 hours off. The break gives them time to rest. I also do this during the warmest times of the day. Which is beneficial in summer and winter. My yields have all been between 5-9 oz per plant. I'm also using 5 Amare lights which I do believe are the most efficient lights on the market. They also have the best spectrum and reach an amazing 93cri. Best of luck and hope this helped

 

[BigSm0]

there is no such thing as too much artificial light. Always run 24/7 unless heat or electricity or stealth is an issue. More light in my anecdotal experience may keep plants shorter and more stout which is what I want. Less light makes them taller which is not what I want. When I was using solar flare 220's I would place one light over one plant and set it about 18 inches above the plant and then move it up again when the plant got to 8 inches below. Almost no leaf problem you mentioned has anything to do with light and in most cases nothing needs to be done if your leaves start acting up. Brown tips, curling, canoing all look like light problems but are just operator error and not serious. Me personally, haven't bought in to the spectrum switch for small growers.

Please remove this comment. If people new to growing read this they may follow your advice and will absolutely ruin their plants.

 

[BII]

Some diverse perspectives so far, but ranging into broader issues than the topic/question I posed -- How much light intensity (in LED terms) is optimal for late veg.? This is not bloom, when it seems prudent to go all out with light; and it is not early veg. when the plants are fragile young plants and you have to go easy with the light intensity. For example, should light level during this period be 100% or perhaps 75% intensity (relative to the highest level to be used, presumably in bloom). And when do you switch from veg. to bloom (where your lights allow this)?

 

[autogogo]

Please remove this comment. If people new to growing read this they may follow your advice and will absolutely ruin their plants.

how so? Show me the auto ruined because it had too much light. They did delete the post. If they're going to delete posts for inaccurate information there are many more (some are mine) which must be deleted. Led is still being haunted by old info which only applies to hid. It's laughable that people think you can have too much led light. Optimal? Well, I suppose you can veg on less light, but what's the point. Or was it 24/7 you disagree with?

 

[Corgy]

A photon is a photon, regardless of the source it originates from...... Read through the links referred to in post [HASHTAG]#5[/HASHTAG]. An understanding of terms such as PPFD, DLI and the Calvin cycle amongst others, when discussing "amounts" of light is helpful....

Here's some HubbaBubbaSmelloScope grown under 2 MarsHydro 600 w reflectors with 3 w diodes 24/7, and I have plenty more pics from running out of height with other plus 1,5 m strains when I took on more than I could handle..... (I blame it on the Autopots, but that's another story....)...... I deliberately kept the bleached parts to see the efficiency of the photon torpedoes..... Lol

Where the footprint of the 2 lights overlap is the prime kill zone....
https://fluence.science/science/par-ppf-ppfd-dli/