Leaf discoloration

Redoctober

Redoctober

Well-Known Member
I'm scared to post pics so I'll do my best to describe this. I'm running an aeroponic system with a 12 gal rez using GH flora series nutes at 570ppm, pH between 5.6-5.9. I'm mixing the nutes in the following ratio 2 parts Micro:3 parts Grow:1 part Bloom. Today I got home and most of the leaves, but not all, looked as though someone had dipped a paintbrush in yellow paint and flung it around on the plants. I've seen pics of nut burn and it usually occurs around the edges so I'm wondering if that's what this could be.

Here's what's changed in the past day that are the possible causes as far as I can tell:
1. I added some water and up'd the ppm to 620 from 570 (this is usual suspect #1)
2. Sprayed the plants with GoGnats solution at bottle recommendation of 13mL per liter of water in order to combat my ongoing spider mite problem.
3. Did some sanding of part of the wall in the room and I noticed some tiny bits of sawdust on the leaves (I covered the rez while I was doing this so as not to contaminate it). Room now smells like sawdust.
4. Because of the sawdust in the roome I put my Oreck air purifier in the room that has some ion air freshener built in which I turned on and let run for 12 hours.

I know that without pics, it's going to be hard for anyone to help me, but does this sound like nut burn from the raised ppm of the nutes? What should I do? Did I permanently damage the plants? I did a rez change 2 days ago with fresh nutes, all I did yesterday was add some water because the plants were drinking a bunch and added some fresh nutes raising the ppm to 620.
 
zem

zem

Well-Known Member
how big are your plants? it can be that they'r hungry, 612ppm is low for grown plants.
 
Redoctober

Redoctober

Well-Known Member
not terribly big. They are vegging, and range in sized from about 7" to 15"
I agree that 612 seemed low for nutrient burn, but I guess in aero, they are more sensitive.
I'm going to do a straight RO water flush for a day and go with 200ppm nutes for a few days and see what happens.
Am I correct in thinking that leaves will not change back to normal once they are burned?
 
zem

zem

Well-Known Member
no they won't, but the discoloration will go and new growth will be healthy. i think it's a good idea to change res but i doubt this size plant will burn with 612ppm overnight. more probably hungry
 
Redoctober

Redoctober

Well-Known Member
hmm. Now I'm really stumped. I went over my notes and found that I had the ppm at around 570 for the past week and was getting nice lush growth, albeit a bit slow. I can't imagine that increasing it from 570 to 620 would cause such a drastic burn, unless nutes had been accumulating or something. I'm totally neurotic when it comes to monitoring pH and check it like 4x a day and make sure it's b/w 5.6-5.9.

Will this leaf burn adversely affect bud production?
 
zem

zem

Well-Known Member
Redoctober said:
Will this leaf burn adversely affect bud production?
Click to expand...
every kind of plant problem affects bud production, how much it affects it depends on severity of it and how well you treat it. since you're still vegging you can grow them back to full health and not notice any difference except for some little lost time
 
Redoctober

Redoctober

Well-Known Member
Thanks zem, I think I may have to post some pics. I did a rez change yesterday and just put in pH adjusted RO water and let it run for 24 hours. I just changed that water out for fresh RO water with GH nutes mixed in the same ratio as above 2 parts micro:3 parts grow: 1 part bloom. I used RO water this time instead of RO/DI so as to include some of the ions that are taken out by the DI resin, which the plants may like. The nutrient mix is at 328ppm in the rez. pH adjusted to 5.65. Room temp is b/w 70-75. Humidity around 30% maybe slightly less at times.

I don't understand this but with just RO water in the rez and nothing else, the burn seems to have worsened. How is that even possible? Also I'm getting some very gnarly leaf curl going on. Not that the sided are curling down, but the leaves are rolling up from the ends and even twisting sideways, so I end up with some "L" shaped leaves. Why do the gods frown upon me? Pics coming soon.
 
thegreensurfer

thegreensurfer

Well-Known Member
did you spray while the lights were on? it resembles light bleaching
you got some major stress going on there with the single leaf shoots, im guessing light stress
 
Redoctober

Redoctober

Well-Known Member
As a matter of fact I have been spraying with the lights on because I thought that with the humidity so low the leaves might need some extra moisture. Is that a no no? Could that be causing some of this? I have been doing this for the past few weeks with no ill effects. The only other thing I can think of is that I sprayed heavily with GoGnats the night before all of this happened.

I think much of the single leaf stress was caused during early veg when the plants remained in the ez cloner with nothing but clonex solution for several weeks too long. I had no choice because I was unable to obtain nutes and other equipment. When they went into the aero unit, they really began making a nice recovery over the past few weeks until 2 days ago when I walked in on that horror show.
 
sparkafire

sparkafire

Well-Known Member
"The only other thing I can think of is that I sprayed heavily with GoGnats the night before all of this happened."

Eliminate the common denominator and you might have your problem. Best thing is to just not to do anything but keep them fed properly and wait it out. The plants will slowly recover and you can move forward.


 
thegreensurfer

thegreensurfer

Well-Known Member
Yea, don't spray with the lights on or you'll fry the leaf. Some will say to spray at lights out but I worry about mold & other moisture related problems
If I need to foliar spray, I'll spray in the bathroom and put in front of a fan for like 30 mins and then back into the flowering room when dry.
 
Redoctober

Redoctober

Well-Known Member
Eliminate the common denominator and you might have your problem. Best thing is to just not to do anything but keep them fed properly and wait it out. The plants will slowly recover and you can move forward.
Click to expand...
I guess that's all I can really do. I replenished the nutes and bumped them up a touch from 320 to 375ppm. I'm going to keep it there for a few days. I'm very aware of overfeeding and burning them, but at the same time I don't want to starve them either so that they are deficient. I'm feeling more and more certain that it was the GoGnats spray that somehow did it. It's pretty evil stuff, it practically melted the bottle it was in. I guess it had been sitting on the grow store shelf for a while.

greensurfer, thanks for the advice; I will make sure I don't spray them while the lights are on anymore. I'm using 2 180W LED lights for veg, I don't suppose that makes a difference where bleaching is concerned? They sure do keep the temps down in the room. I can literally put my hand on them after they've been on for hours (I don't do this of course because I'll get fingerprints all over them). What's funny is that I've been foliar spraying with the lights on for the past week and a half with no problems, then all of a sudden BOOM! That's why I tend to think that this GoGnats spray is the culprit. What's even stranger is that I have two clones that only have root bumps in the unit, and they were completely unaffected. So who knows, there's a lot of variables unfortunately because I did a bunch of things all at once. Now I know not to do that.
 
mr.sessemia

mr.sessemia

Well-Known Member
it look to me like ther may be a combination of of a nutrient problem and how much yore watering in picture two youre leaves are drooping and curling inward the drooping can come from your plants being thirsty,......and in pics 1 3 and 6 i would definately say that a chemical burn here the grow ratio i use for vegging i use a 3:1:5 ratio and for budding i use a 1:0:1 ratio for me it works great......hope it helps
 
thegreensurfer

thegreensurfer

Well-Known Member
I've heard of the led's burning leaves if they are too close
but as long as new growth is good you're fine.
Typically, you wont have to spray for gnats, just a soil drench is necessary, I use azamax and its very effective
i hope things get better soon
 
Redoctober

Redoctober

Well-Known Member
it look to me like ther may be a combination of of a nutrient problem and how much yore watering in picture two youre leaves are drooping and curling inward the drooping can come from your plants being thirsty,......and in pics 1 3 and 6 i would definately say that a chemical burn here the grow ratio i use for vegging i use a 3:1:5 ratio and for budding i use a 1:0:1 ratio for me it works great......hope it helps
Click to expand...
Thanks mr.sessemia. Are those ratios micro:grow:bloom formula with GH or are they nitrogen-phosphorus-potassium ratios? I have altered the misting schedule from 1 min on, 9 min off to 45s on, 5 min off. They do seem to be drinking a lot now, and the new leaves don't seem to be curling (fingers crossed) although the older ones refuse to uncurl.

I've heard of the led's burning leaves if they are too close
but as long as new growth is good you're fine.
Typically, you wont have to spray for gnats, just a soil drench is necessary, I use azamax and its very effective
i hope things get better soon
Click to expand...
Thanks greensurfer, me too. I have a stadium sort of a setup so some of the plants are closer than others to the lights. I did a little experiment where I intentionally misted a few leaves with lights on to see if they would burn or change color. I haven't noticed anything yet but I'm trying to eliminate possibilities one by one. I was actually using the GoGnats for spidermites because that was what the hydro store guy recomended, but I shant be using that stuff again any time soon. I've tried 3 or 4 different things on the mites and nothing seems to get rid of them. They're such resilient little bastards. I was even considering predator mites (I like the idea of them because I like to imagine that they are like actual Predator i.e. they have a suit that makes them invisible, a shoulder mounted plasma cannon, and a small tactical nuke in case they are captured)! I've taken a few clones from my plants and if they work out, I may just start over, it's kinda demoralizing.
 
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