Too much lite ! Stunted plants

[The70’s]

Im looking over my past grows and my current plants are surely stunted. They are approaching 8wks in veg and while they are green now, i definitely think this grow was hampered by too bright lites and too much nitrogen…..

Have you encountered this in any grows

 

[Chuckeye]

More info needed, light model, watts from the wall/medium/nutrients, etc..

But....does your light have a power knob ?

Are you measuring lux/par values ? From the top of the plant(s) to the light...

VERY Important !

Cheers

PS> you can download a free lux meter for your phone and use a conversion factor of .015 to get par values.

 

[Ke0ncp]

Agree with Mr. Chuck there!

Though, plants that are getting lots of light can be bushier, not a bad thing, and appear stunted.

 

[Delps8]

The amount of light doesn't significantly impact the shape of a plant. More light allows plants to photosynthesize more (that's how plants make food) which allows it to grow more.

The spectrum of a light impacts the shape. A standard LED grow light has a balance of blue and red photons because blue photons tend to make plants short and compact but plants grow taller in response to red photons.

A plant that receives a lot of light will tend to have a large number of smaller leaves and will not stretch the way a plants that are under lighted do.

A plant that receives too much light will have leaves that have a curled and, in extreme cases, will show damage.

What light are you using and what's your PPFD or dimmer setting and hang height. Pictures would help.


The plants in both of these pictures were topped and LST'd and grown at >1000µmol.

 

[Fenderbender]

How bright were those lights?? Too much N has hampered many grows, definitely encountered that.
Too much light not yet as you need a lot of light for that too happen, too close yes, encountered that as well

And trying to grow high octane by giving everything in spades can lead to great results if done and timed right but it can also indeed stunt the growth.
I'm done with feeding schedules and trying to grow like a commercial grower. I try to setup good initial conditions and then see how she fares.
Currently back to sips with soil and first time using GW mycorrhiza and sweet jebus I feel like I'm growing cabbage.
14 day old Strawberry Cookies seedling.

 

[JCVAP]

I've encountered a similar situation. Too much nitrogen and overly bright lights can both stunt plant growth. Excess nitrogen can lead to very dark green leaves and stalled growth, especially during the vegetative stage. As for lighting, if the lights are too close or too intense, plants can show signs of light burn, which limits growth. You might notice leaf edges curling or yellowing, and overall plant health can suffer.

I’d recommend dialing back the light intensity or raising the lights higher to give the plants some relief. Also, cutting down on nitrogen, especially in the vegetative stage, and switching to a more balanced nutrient plan might help alleviate the issue.

Since your plants are green now, it sounds like they’re recovering. Giving them a bit more time to adjust could lead to improvement. Hope this helps!

 

[The70’s]

More info needed, light model, watts from the wall/medium/nutrients, etc..

But....does your light have a power knob ?

Are you measuring lux/par values ? From the top of the plant(s) to the light...

VERY Important !

Cheers

PS> you can download a free lux meter for your phone and use a conversion factor of .015 to get par values.

MedicGrow fold-8/GLC-1
DLI 40/Par 600ish
About 16” from canopy

Watts 329

Soil w/gaia green 444

Worm castings

Lites On 76° RH 65%

Lites Off 69° RH 60%

To be fair i was adding calmag+ in the beginning because they were in small cups with plain living soil, then when transplanted in bigger pots, i added calmag+ a few times with watering to the bigger pots that had super soil of GaiaGreen 444 and Workcastings


These girls are in week 7 going into week 8 soon

 

[Chuckeye]

MedicGrow fold-8/GLC-1
DLI 40/Par 600ish
About 16” from canopy

Watts 329

Soil w/gaia green 444

Worm castings

Lites On 76° RH 65%

Lites Off 69° RH 60%

To be fair i was adding calmag+ in the beginning because they were in small cups with plain living soil, then when transplanted in bigger pots, i added calmag+ a few times with watering to the bigger pots that had super soil of GaiaGreen 444 and Workcastings


These girls are in week 7 going into week 8 soon

Nothing jumps out to me about your numbers. Plants look good now !

What was your par and age at transplant ? Pictures at that stage ?

Is this the first time using that "soil" ? I'm a soilless guy trying coco for the first time

First time running that strain ?

Whatever wasn't quite right happened in week 2 - 4 and it is more likely to do with your soil than your light !

Cheers

 

[bluter]

there's no way that light can produce too much for those plants. from the pic i'd have to say it's deeper into the blue spectrum than anything i like to run. sure wouldn't call it a flower bias.

most of the newer gen full spec lights i see are all leaning far too heavy into the blue. i still prefer a flower bias, as that's where all the fun is, and i veg under lights with a flower bias just fine.

 

[Fenderbender]

MedicGrow fold-8/GLC-1
DLI 40/Par 600ish
About 16” from canopy

Watts 329

Soil w/gaia green 444

Worm castings

Lites On 76° RH 65%

Lites Off 69° RH 60%

To be fair i was adding calmag+ in the beginning because they were in small cups with plain living soil, then when transplanted in bigger pots, i added calmag+ a few times with watering to the bigger pots that had super soil of GaiaGreen 444 and Workcastings


These girls are in week 7 going into week 8 soon

Wowie what a nice setup, space and light for days, fans everywhere, humidifier-s, height adjustable plateaus.
And the plants look pretty nice!
Could they be a bit bigger at week 7 yeah maybe but they are growing nice big leaves.
These lights seem to be available in different spectrums? 660+ 3000&5000k or 3000&4000k
Maybe if it's more blue leaning one keeps the plants short & stubby does not promote extension growth?

 

[bluter]

Maybe if it's more blue leaning one keeps the plants short & stubby does not promote extension growth?

blue will promote stretch, branching, and leaf development a bit in veg and shorten veg time. my plants take longer to veg because the bias my lights have is wrong for veg.

the problem with "full spec" lights is they simply can't be everything. there is always a compromise of some sort.

 

[Delps8]

MedicGrow fold-8/GLC-1
DLI 40/Par 600ish
About 16” from canopy

Watts 329

Soil w/

green 444

Worm castings

Lites On 76° RH 65%

Lites Off 69° RH 60%

To be fair i was adding calmag+ in the beginning because they were in small cups with plain living soil, then when transplanted in bigger pots, i added calmag+ a few times with watering to the bigger pots that had super soil of GaiaGreen 444 and Workcastings


These girls are in week 7 going into week 8 soon

Your plants look really good. Only comment about the grow environment, well two.

Are you sure you have enough fans? ;-) Nah, they look great.

You RH is high for 76°. That temp + RH is excellent for germination but those plants are well into veg so, at that temperature, dropping to 60% will allow the plants to transpire more and just that small drop in RH helps ensure that you don't run into mold.

Re. the light - per this page, that light gives you a choice of two spectra. The "F1" has a higher ration of red to blue and I suspect that the "F" stands for "flower", while the "V1" looks to have more blue in it than the F1 and "V1" would mean it's for veg.

If you're using the V1, that would explain why you have "short, compact" plants - that's the typical description for plants grow under a blue heavy light. The advantage is that it's easy to work with plants that are short and compact, they tend to be physical stronger, they're easier to harvest, and they tend to have a more even vertical distribution of cannabanoids than plants that are tall.

A flower light, with more red, will tend to product plants that are tall (because they don't have a lot of blue photons). If you're used to growing with HPS, you've seen tall plants because HPS has a tiny amount of blue, just enough to stop plants from being malformed.


Screenshot from a Bugbee video.
View attachment 3673575


Vegged under a Growcraft veg light and then a G'craft flower light. 30" x 24" by 24" tall. A joy to work with.

Check the label on the light or maybe an invoice — which version off the Fold 8 are you using?

 

[Fenderbender]

blue will promote stretch, branching, and leaf development a bit in veg and shorten veg time. my plants take longer to veg because the bias my lights have is wrong for veg.

the problem with "full spec" lights is they simply can't be everything. there is always a compromise of some sort.

I was under the idea that red causes stem elongation and blue yes good for vegging but keeps things more compact & stout.

 

[Delps8]

I was under the idea that red causes stem elongation and blue yes good for vegging but keeps things more compact & stout.

Yes on the blue but red, in and of itself, doesn't cause cell expansion. Plants grown with a lot of red are taller than plants that get a lot of blue because a red-heavy spectrum doesn't have blue photons to inhibit cell expansion.

Red light is more photosynthetically efficient, as well.

The old school lights, MH and HPS, did things well but they're inefficient compared to LED. I think the optimal approach, in terms of yield and morphology, is to go with separate veg and flower lights but that dramatically increases cost. A suitable compromise, in my mind, is what @bluter brought up, which is to not worry too much about compact and go with a light with more red. Unless you're growing in a 2' x 2', I think that's the smart move.

 

[Fenderbender]

I use Sanlight EVO now and my plants have been growing way bigger in all regards since I got it, bigger stems bigger plants.
I did one auto & two photo grows now in the third.
Their spectral colour distribution is Blue 14% Green 37% Red 45% Far Red 4% like the Led array +-

 

[The70’s]

Wowie what a nice setup, space and light for days, fans everywhere, humidifier-s, height adjustable plateaus.
And the plants look pretty nice!
Could they be a bit bigger at week 7 yeah maybe but they are growing nice big leaves.
These lights seem to be available in different spectrums? 660+ 3000&5000k or 3000&4000k
Maybe if it's more blue leaning one keeps the plants short & stubby does not promote extension growth?

Had no idea that was a thing, the different outputs, thanx, im hoping the company can check by serial number, not too sure where the receipt is…

Are you sure you have enough fans? ;-) Nah, they look great.

You RH is high for 76°. That temp + RH is excellent for germination but those plants are well into veg so, at that temperature, dropping to 60% will allow the plants to transpire more and just that small drop in RH helps ensure that you don't run into mold.

Re. the light - per this page, that light gives you a choice of two spectra. The "F1" has a higher ration of red to blue and I suspect that the "F" stands for "flower", while the "V1" looks to have more blue in it than the F1 and "V1" would mean it's for veg.

If you're using the V1, that would explain why you have "short, compact" plants - that's the typical description for plants grow under a blue heavy light. The advantage is that it's easy to work with plants that are short and compact, they tend to be physical stronger, they're easier to harvest, and they tend to have a more even vertical distribution of cannabanoids than plants that are tall.

A flower light, with more red, will tend to product plants that are tall (because they don't have a lot of blue photons). If you're used to growing with HPS, you've seen tall plants because HPS has a tiny amount of blue, just enough to stop plants from being malformed.


Screenshot from a Bugbee video.
View attachment 3673575


Vegged under a Growcraft veg light and then a G'craft flower light. 30" x 24" by 24" tall. A joy to work with.

Check the label on the light or maybe an invoice — which version off the Fold 8 are you using?

Again, i had no idea there were different “versions” that is so cool…

 

[bluter]

i had no idea there were different “versions” that is so cool…

i run a mix of 3000k and 3500k. looks super warm in pics.

it's really yellow compared to most leds. almost like an old hps.