Could this be anything other than light bleaching?

TrentSteel

Active Member
I'm quite positive I have light burn/bleaching on my plants but I just wanted a second opinion.

Reason being I had an overwatering issue, so I let my plants dry out much further than usual (organic living soil). I'm aware that occasionally after watering really overdried soil, the nutrients in the solution can become concentrated and cause a sort of minimal nute burn.
Now I'm quite positive nute burn does not look like this but I just wanted to confirm with you guys.
I recently switched from a Mars HydroTs1000 to an Aelius 300. The Aelius lighting uses a spectrum with far more red and blue spectrum and very minimal yellow/green, I believe this has my plants showing burn on average 100 PAR lower than with the Mars Hydro.
 

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FirstCavApache64

Well-Known Member
It looks to me like the tip burn I get from my small organic fabric pots drying out too much. It happens when I use 3 instead of 5 gallon pots and let them dry out too often. I don't understand the mechanism of it but like you said I believe it concentrates the organic nutes and causes mild tip burn. It looks like classic nute burn as it progresses. I just see it on the leaves down low as well as up top and the top leaves aren't showing any other signs of light stress like canoing, tacoing or getting really serrated looking. Just keep up with the watering and they should be fine.
 

TrentSteel

Active Member
It looks to me like the tip burn I get from my small organic fabric pots drying out too much. It happens when I use 3 instead of 5 gallon pots and let them dry out too often. I don't understand the mechanism of it but like you said I believe it concentrates the organic nutes and causes mild tip burn. It looks like classic nute burn as it progresses. I just see it on the leaves down low as well as up top and the top leaves aren't showing any other signs of light stress like canoing, tacoing or getting really serrated looking. Just keep up with the watering and they should be fine.
Thank you very much this is the answer I was hoping I would get.
 

FirstCavApache64

Well-Known Member
I feel like my PAR should be a pinch higher but this has me holding back.
Do you have a lux meter or light meter to measure it? I just got one after a few years of growing and it sure is nice to be able to measure the light finally. If you do, what measurement are you getting?
 

Delps8

Well-Known Member
Plants look very dark green so I'd guess they don't need any more nitrogen. :-)

Re. light - good that you're watching your plants but I don't see anything that looks like too much light. With LED's, plants will exhibit signs of light avoidance initially such as rotation the leaf around the axis of the petiole or "tacoing". I pushed some of my colas a little too much in my last grow (940µmols) and the colas actually bent away from the light. Pretty interesting.
 

TrentSteel

Active Member
Do you have a lux meter or light meter to measure it? I just got one after a few years of growing and it sure is nice to be able to measure the light finally. If you do, what measurement are you getting?
I don't but I borrowed one from a friend and took a lot of notes at different heights and dim %s. So it's kind of an eyeball situation.

In my eyes I'm prob sitting around 320-420umols, which shouldn't be giving me any issues but I have read the lights using much more blues and reds can cause burn at lower PAR, I wasn't sure just how dramatic the difference is. I guess I'm still not to sure.
 

FirstCavApache64

Well-Known Member
Plants look very dark green so I'd guess they don't need any more nitrogen. :-)

Re. light - good that you're watching your plants but I don't see anything that looks like too much light. With LED's, plants will exhibit signs of light avoidance initially such as rotation the leaf around the axis of the petiole or "tacoing". I pushed some of my colas a little too much in my last grow (940µmols) and the colas actually bent away from the light. Pretty interesting.
I never knew that the leaf blade rotation around the petiole was a light stress reaction. It seemed to come around the stretch usually so I assumed it was a rapid growth related issue.Thanks for that!
 

Delps8

Well-Known Member
I never knew that the leaf blade rotation around the petiole was a light stress reaction. It seemed to come around the stretch usually so I assumed it was a rapid growth related issue.Thanks for that!
You're welcome.

Any chance you knew a WO named Jeff Morris? He was my roommate at Ft. Bragg in the mid-80's — I went to OCS and Jeff went to Rucker. I pinned his wings on when he graduated.
 
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TrentSteel

Active Member
Agreed but it's just at the tips which, in my limited experience, indicates that it's a nutrient issue.

Per First CavApache 64 (great aircraft BTW), a PAR meter or a lux meter would help shed some light on the issue.

What light are you using?
Thank you..

This is the light..
 

Delps8

Well-Known Member
Thank you..

This is the light..
That light certainly can put out enough light to cause bleaching but, per the other posts, that's probably not the issue. It would help if you can get light plan info from the manufacturer. A PAR meter will remove all doubt but, lacking that, you'll get a ballpark figure with a lux meter and you can fine tune it from there.
 

TrentSteel

Active Member
That light certainly can put out enough light to cause bleaching but, per the other posts, that's probably not the issue. It would help if you can get light plan info from the manufacturer. A PAR meter will remove all doubt but, lacking that, you'll get a ballpark figure with a lux meter and you can fine tune it from there.
Oh I have a lux metre from my HPS days, I just figured it was useless. Can that help me?
 

FirstCavApache64

Well-Known Member
You're welcome.

Any chance you knew a WO named Jeff Morris? He was my roommate at Ft. Bragg in the mid-80's — I went to OCS and Jeff went to Rucker. I pinned his wings on graduation.
No. Doesn't ring a bell. I worked with some great pilots though. I was at Ft Hood from 99-2002 with the First Cavalry Division, 1/227th. We were a Longbow squadron of nutjobs. I got injured in 2002 and was medically discharged.
Ft. Bragg in the mid 80s was a pit, I feel for you. My Uncle was a Ranger and Green Beret and was stationed there after his third tour in Vietnam. He was on the Golden Knights jump team and we went down to watch them jump in the late 70s. Sorry to threadjack op.
 

FirstCavApache64

Well-Known Member
Oh I have a lux metre from my HPS days, I just figured it was useless. Can that help me?
Yup. It will give you a good rough idea with true white LEDs. It won't work with blurples though, I can't remember the science of why, just that it's not accurate with blurples.
 

TrentSteel

Active Member
Yup. It will give you a good rough idea with true white LEDs. It won't work with blurples though, I can't remember the science of why, just that it's not accurate with blurples.
Ah, true. I actually recall trying to use it on a blurple I don't think it gave me any readings at all or they were so low I knew it wasn't close to accurate.
Np on the threadjackin I don't mind.
 

Delps8

Well-Known Member
No. Doesn't ring a bell. I worked with some great pilots though. I was at Ft Hood from 99-2002 with the First Cavalry Division, 1/227th. We were a Longbow squadron of nutjobs. I got injured in 2002 and was medically discharged.
Ft. Bragg in the mid 80s was a pit, I feel for you. My Uncle was a Ranger and Green Beret and was stationed there after his third tour in Vietnam. He was on the Golden Knights jump team and we went down to watch them jump in the late 70s. Sorry to threadjack op.
Just thought I'd check.
"medically discharged." Hope you're doing well.

"Sorry to threadjack op."
Same.
 
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