What tools to determine why my plants are yellowing?

  • Thread starter Shagreezz3
  • Start date
  • Tagged users None
S

Shagreezz3

12
3
Roots Organic original soil, nothing else added (see later when dry amendments were added) week 15 of veg, been giving only water (no liquid nutes at all), yellowing started after adding a little more Roots Organic and Kelp Meal 1-0-1-2, added this around week 12, thinking that was the cause for the yellowing, i removed extra Roots and kelp meal (just dumped everything i topped the soil off with) after about a week and a half of this, been about two weeks since, no improvements with new growth, vpd has been pretty steady at 0.9 -1.3, is that range too wide?





I ph the water going in to about 6.5 (color coded not electronic) i have not tested my soils ph, if this is the next step, do you recommend any specific brand of a ph tester?

Any help is greatly appreciated, also let me know if I need to add any more details

My set up is basically this ac infinity advanced grow tent, did not buy anything extra to add to the tent

 
What tools to determine why my plants are yellowing
What tools to determine why my plants are yellowing 2
Shaded_One

Shaded_One

1,866
263
Welcome to the farm šŸŒ²

Not a terribly accurate answer but too much N & not enough P or K for the stage of growth. That's usually one problem with "set it and forget it" types of soils. She looks a little light or heat stressed as well which could be playing a part.
 
S

Shagreezz3

12
3
Welcome to the farm šŸŒ²

Not a terribly accurate answer but too much N & not enough P or K for the stage of growth. That's usually one problem with "set it and forget it" types of soils. She looks a little light or heat stressed as well which could be playing a part.
I thought it could be the lights (even though it was closer than it is now the whole grow) and pulled them ALL the way up, high as I can, and I still get this, temp is usually about 80F or lower, there have been days where I come home, check the monitor and it hit 90 during mid day, but that was only a few times during summer, past 2-3 weeks been steady around 80, too high?
 
S

Shagreezz3

12
3
I had that problem a year or so ago. My problem was my lights were to close. The yellowing and necrosis of the tips looked identical to yours.

Try to back your light off.
Interesting two of you mentioned the lights, im going to take a pic when i get home but i have moved them as far away from the plant as possible and its in the lowest setting

Temps avg around 80f , think this cud be a reason? I want to put these into flower but afraid to do so without addressing this yellowing
 
S

Shagreezz3

12
3
Thanks for this, ive seen it before, however, how do i determine like yes it 100% is lacking copper (just random example) before i go adding stuff in? The leaves look similar to a few issues on that page, i dont want to over do it and start adding too much stuff and make things worse if that makes sense? Really appreciate the response though
 
N1ghtL1ght

N1ghtL1ght

Staff
Supporter
670
143
Your plant is small for that long veg. Try to give it more light, at least, try to figure out its sweet spot because that has quite some effect on how roots can develop and then intercept nutrition.
 
S

Shagreezz3

12
3
I agree it does look similar, but i feel it looks even more like the light burn/light stress pics they have up there, so confused right now as to how to move forward

Edit: would you suggest i try adding some P since I already have my lights as far away as possible? Also is there like an actual test i can do to determine what is causing this for sure? Thanks for all your help, i think your onto something with this , recommend any product?
 
Habosabin

Habosabin

1,198
263
I agree it does look similar, but i feel it looks even more like the light burn/light stress pics they have up there, so confused right now as to how to move forward

Edit: would you suggest i try adding some P since I already have my lights as far away as possible? Also is there like an actual test i can do to determine what is causing this for sure? Thanks for all your help, i think your onto something with this , recommend any product?
If you can download the Photone app then you can measure an approximation of your DLI or par to determine if itā€™s to strong. Do you have a dimmer function on light?

I tend to think it's not the light since most of the mottled leaves is below the halfway point.

It's either ph or deficiency is my guess but I haven't not experienced enough to be sure.
 
Habosabin

Habosabin

1,198
263
Interesting two of you mentioned the lights, im going to take a pic when i get home but i have moved them as far away from the plant as possible and its in the lowest setting

Temps avg around 80f , think this cud be a reason? I want to put these into flower but afraid to do so without addressing this yellowing
80f is fine.
 
Habosabin

Habosabin

1,198
263
Thanks for this, ive seen it before, however, how do i determine like yes it 100% is lacking copper (just random example) before i go adding stuff in? The leaves look similar to a few issues on that page, i dont want to over do it and start adding too much stuff and make things worse if that makes sense? Really appreciate the response though
I would rule out ph first before adding nutes.
 
S

Shagreezz3

12
3
tell us all about your light
Product and Mounting Dimensions - LED Grow Light
Light Dimensions 23.62 x 23.62 in. (60.0 x 60.0 cm)
LED Board Thickness 0.43 in. (1.1 cm)
Driver Dimensions 10.74 x 1.75 in. (22.5 x 4.5 cm)
Product Performance and Technical Specs - LED Grow Light
Coverage 4 x 4 ft.
Diodes Samsung LM301B
LED Chip Count 1024
LED Driver AC Infinity Proprietary Driver, Model GTS-100
Efficiency 2.75 Āµmol/j
PPFD 1937 PPFD
Spectrum 660nm, 730nm, 3000K, 5000K
Wattage 400 W
Voltage 100-277V AC
Frequency 50/60 Hz
Current 2.0 A
Controller Digital Dimming Timer
Power Connector Type US Plug (NEMA 1-15 Type-A)
Operating Humidity 35 to 85% RH
Operating Temperature 32 to 140Ā°F
Life Expectancy 50,000 Hours
 
mysticepipedon

mysticepipedon

4,738
263
It could easily be both a potassium deficiency AND light burn.

What seems to happen with LEDs is Leibig's Law of the Minimum rears its ugly head. Suddenly there's more light, so some nutrients become the limiting factor in plant growth. It seems like this is especially true of potassium and magnesium -- the burn looks like the deficiency symptom.

BTW, when you get a mobile nutrient deficiency, like K or Mg, those deficiency symptoms on the lower leaves never go away. You know you've solved the problem when the symptoms stop creeping up the plant toward the top.
 
Habosabin

Habosabin

1,198
263
It could easily be both a potassium deficiency AND light burn.

What seems to happen with LEDs is Leibig's Law of the Minimum rears its ugly head. Suddenly there's more light, so some nutrients become the limiting factor in plant growth. It seems like this is especially true of potassium and magnesium -- the burn looks like the deficiency symptom.

BTW, when you get a mobile nutrient deficiency, like K or Mg, those deficiency symptoms on the lower leaves never go away. You know you've solved the problem when the symptoms stop creeping up the plant toward the top.
Good info. Is this because the light intensity caused the plant to use all of its reserves and shows as a deficiency? Do you solve this my reducing light or increasing nutes?
 
Habosabin

Habosabin

1,198
263
Ok, should i just go on amazon and type in soil ph tester?
Get a decent one. Not those $10 ones. If you drop those in the tank they are toast. I had an Apera that was nice but the probe wore out so I think one with a replaceable probe would be a plus.

You might be able to do a run off or slurry test with what you have.

I switched to hydro to avoid soil issues. šŸ˜€
 

Latest posts

Top Bottom