White big spots

[Fulflam]

Hey everyone, new here. I have white, comparebly big spots on some of the leaves. I did’t think it is spider mites or white powdery mildew. What do you think? What might cause them?

 

[Phytoplankton]

Hard to tell, the first picture lower leaf almost looks like light burn. The upper leaf in the first picture and the the third picture look different, like either bugs or perhaps water got spilled on the leaves during watering. Take a good look at the undersides of a couple of the affected leaves with a jewelers loop or microscope, look for bugs, or little black specks (bug poop). If that's negative, just keep a close eye on it and see if it progresses.

 

[SmokingWings]

My first thoughts are that in the first photo the leaf that the finger is touching looks like a mild case of light or wind burn. The damage on the leaf below looks like the start of some sort of nutrient deficiency. Then in the second photo the damage looks like more deficiency symptoms or possible insect damage. Plus in the second photo there are more spots showing up not including the little bit on the tips of some of the leaf fingers.

Take a good look at the undersides of a couple of the affected leaves with a jewelers loop or microscope, look for bugs, or little black specks (bug poop). If that's negative, just keep a close eye on it and see if it progresses.

Yes, inspect the underside. Include looking for spots that are showing on both sides. Some insects will damage the one side that they feed on. Sometimes their damage goes all the way through and the areas will turn dry and in those cases will open up into a hole.

My first photo is a sample of light burn from LED T5 tubes and we can see some of the wilting and twisting of the leaf fingers.

light-burn02.jpg

• SmokingWings
• Sep 16, 2022

light burn 2 inches from LED pod, moved plant away 40 hours before photo taken with P&S.

This photo below is looks like the same sort of damage but it is a case of wind burn from the plant being too close to the fan.

wind-burn01.jpg

• SmokingWings
• May 11, 2020
• wind burn windburn

Wind burn damage

Just some examples that might be able to help pinpoint what your problem spots could be.

 

[Azimuth]

Those brown spots could be a building calcium deficiency. Can you tell us about your setup? Grow mix, nutes, watering schedule, etc.

 

[Fulflam]

Hey, thank you all for your opinions. I’m uploading new photos. I’ve searched undersides of leaves but with naked eye, since i do not have a microscope. Couldn’t see any bugs etc.
I have a 60x60x180 tent with bestva led (1000) 2 small fans one is directed to the pot and the other is directed to the plant. I have a 39lt fabric pot. I’m using biobizz fishmix, bioheaven, cal-mag (for prevention) and algamic (when i give high stress) with half dosages written in the schedule. Just with my last watering i gave full dosages. I’m uploading some more pics about my setup.

 

[Azimuth]

Hmm. The cal-mag should handle a Ca deficiency so maybe something else.

 

[Fulflam]

I’m not sure about the ph accuracy. My ph meter acted wierd a couple of times. The only thing comes to my mind is this.

 

[cbdhemp808]

Hey @Fulflam and welcome to the forum!

I think your plant is too healthy . Really, those necrosis spots are few and isolated, not systemic. I'd say don't worry about it and check back with us if it gets worse.

happy growing!

 

[Fulflam]

Hey @Fulflam and welcome to the forum!

I think your plant is too healthy . Really, those necrosis spots are few and isolated, not systemic. I'd say don't worry about it and check back with us if it gets worse.

happy growing!

Hey, thank you so much!!
Yes signs don’t have a pattern but there are similar signs on 4-5 leafs. I’ll be watching and informing / asking for help here.