Light or heat stress? Or deficiency?

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dbrzz

dbrzz

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Hey so my two plants the leaves all seem to be turning a pale color and also yellowing from outside in with little burn on couple leaves but not much but they are a real pale almost pastel green kinda. Pics don’t really show exactly how they look. What would be causing this most likely? I am running one spider farmer sf4000 at the moment above the two plants about 24inches. Thought it might be light stress or something so I raised it yesterday to about 30inches above tops. The runoff on the first plant seemed to be in range around 6.3pH when I fed with nutrients yesterday pH to 6.5 although the one in back runoff was about 7 possibly higher…I used a chemical drop to test water. I fed each plant about a gallon of water. Two gallons mixed with fox farm trio big grow 6tsp, big bloom 6tsp, and 2 tsp of cal mag pH to 6.5. Haven’t looked at them since I watered them yesterday. Here are some pics. They have been in veg for a long while, longer then I ever have done. They sprouted from seed on 7/26/21 so it’s been like about 10 weeks from when they first emerged. They are gelat.og feminized. Originally had them in a 2x2x4 with one spider farmer sf1000 until they got way to crowded then I moved them into the 4x8 and am currently only running the one sf4000 that’s directly above them. Had pH issues due to someone else who is inexperienced watering them when I couldn’t be there with tap water. Which wouldn’t have been an issue cause first dozen times I tested tap pH it was steady 6.5-6.6 although I have since been testing and noticed it fluctuates in pH and sometimes is 7pH or higher. So I flushed both couple weeks back and things were good and seemed to help. Got runoff back to 6.3 range on both. Although that was before and now I need to figure out what the issue is now ASAP. Trimmed a lot of yellow discolored leaves off recently and they are all mostly looking the same now yellowing from outside edges and or just light pale color. I realize this is probably a lot and am probably rambling a bit but you guys have been awesome and I know if anyone can help me solve these issues it is this community, thanks 🙏 🙂
This is a magnesium deficency. I suspect your using coco coir mix. When using coco medium, cal/mag preparations added to the nute mix cause high levels of calcium in the coco medium which locks out the magnesium. I use only epson salt for adding magnesium to the mix. Use a base formula with added calcium I like 7% in my veg formula.
 
Cannabisoldier

Cannabisoldier

1
3
This is a magnesium deficency. I suspect your using coco coir mix. When using coco medium, cal/mag preparations added to the nute mix cause high levels of calcium in the coco medium which locks out the magnesium. I use only epson salt for adding magnesium to the mix. Use a base formula with added calcium I like 7% in my veg formula.
I thought he said he was using Fox Farm Ocean Forest. Could be Calcium or Magnesium. 50% RH isn't bad I like to be around 65 - 75 RH. RH affects caclium uptake. Perhaps, you already knew this. If you have grown this strain under this light under these conditions previously, and none of these issues were present, then perhaps its a pest or pathogen. Also, as others have stated it could be mild light stress. Do you have a light meter of any kind. The higher your DLI/PPFD, the more your nutrients and environment will have to be on point. I know you don't suspect it is overwatering. But it is possible it HAD been overwatered. It could be a mild pythium infection in its early stages. But first things first. Make sure ph is solid. And if you can bring up the RH a bit to around 65 so the babies can uptake more calcium. Youre not doing anything "wrong" but for some reason your ladies are mildly upset. I always start with PH and VPD. Then possible pests or pathogens...that is, if Im using my tried and true nutrient formulas that are always on the money, so I can rule them out as suspect. I'll look at the pics a lil more to see if anything comes to mind.
 
Mrb53

Mrb53

221
63
I agree on the Mg issue here as a main player in the problem department. Something is up with the nutes and watering rarely plays a major role in nutrient issue. Something is locking the nutes.
I do not see - P or K issue, I do see a little N issue adn overwatering can cause that. The leaves do look swollen and that point to overwater. Do not confuse over watering with watering too often, there is a difference. In a good or even just devent substrate, and cloth bags, it is pretty hard to overwater but easy to water too often. I also do not agree that PRAYING is light stress...almost every plant I grow is in stress based on that and it is what I aim for.
I do NOT see temp or Ph or RH (RH maybe) issues that STICK OUT. When you got problems, they identify themselves with telltale signs. Your keeps prompting me with Magnesium. too much Calcium can lock out mg, Magnesium is highly mobile in the plant and deficiency symptoms first appear on the lower leaves. Symptoms are more severe on the lower leaves because magnesium is moved to the new growth. Deficiency symptoms consist of interveinal chlorosis (leaf veins stay green while the regions between them turn lighter). The PASTEL green indicates N issue. This can also be a result of Ca & Mg...Issues like this take 2 to 3 weeks to become evident since it takes the plant that long to respond to a soil / substrate condition. The fact you had higf Ph runoff kind of shows you had a slat issue and that is just overfeeding / hot soil / synthetics. You flushed and that helped and that right there is a very good indicator of some of the problem.
Nutrients from the substrate up take a cpl weeks to work. SPRAYS work in a cpl DAYS! N is an easy fix, just use ammonia (many use male urine (make sure no pathological problems). Urine is sterile and turns to ammonia in 1 day. A SHOT in a half gal of water and spray will turn things green in just a day or 2...never when lights are on! Never female urine as the hormones are different. Epson salt also in a spray bottle is absorbed in just a day or 2.
 
Aqua Man

Aqua Man

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😆 ive never had that issue but ok.
It's an early indication of light stress. Notice how not all of your leaves are "praying" only the uppermost closest to the light?

The cupping or folding is the plant reducing its surface area and inturn its capture of light.


So laugh all you want but that's exactly what it is. At that stage it's not necessary causing physical damage but that doesn't mean it's not stress.
 
Aqua Man

Aqua Man

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I agree on the Mg issue here as a main player in the problem department. Something is up with the nutes and watering rarely plays a major role in nutrient issue. Something is locking the nutes.
I do not see - P or K issue, I do see a little N issue adn overwatering can cause that. The leaves do look swollen and that point to overwater. Do not confuse over watering with watering too often, there is a difference. In a good or even just devent substrate, and cloth bags, it is pretty hard to overwater but easy to water too often. I also do not agree that PRAYING is light stress...almost every plant I grow is in stress based on that and it is what I aim for.
I do NOT see temp or Ph or RH (RH maybe) issues that STICK OUT. When you got problems, they identify themselves with telltale signs. Your keeps prompting me with Magnesium. too much Calcium can lock out mg, Magnesium is highly mobile in the plant and deficiency symptoms first appear on the lower leaves. Symptoms are more severe on the lower leaves because magnesium is moved to the new growth. Deficiency symptoms consist of interveinal chlorosis (leaf veins stay green while the regions between them turn lighter). The PASTEL green indicates N issue. This can also be a result of Ca & Mg...Issues like this take 2 to 3 weeks to become evident since it takes the plant that long to respond to a soil / substrate condition. The fact you had higf Ph runoff kind of shows you had a slat issue and that is just overfeeding / hot soil / synthetics. You flushed and that helped and that right there is a very good indicator of some of the problem.
Nutrients from the substrate up take a cpl weeks to work. SPRAYS work in a cpl DAYS! N is an easy fix, just use ammonia (many use male urine (make sure no pathological problems). Urine is sterile and turns to ammonia in 1 day. A SHOT in a half gal of water and spray will turn things green in just a day or 2...never when lights are on! Never female urine as the hormones are different. Epson salt also in a spray bottle is absorbed in just a day or 2.
I have to disagree with much of this.

watering rarely plays a major role in nutrient issue.

Overwatering and even underwatering to a lesser degree has absolutely HUGE consequences on nutrient uptake.

Do not confuse over watering with watering too often, there is a difference. In a good or even just devent substrate, and cloth bags, it is pretty hard to overwater but easy to water too often
Overwaterimg is not watering to much at one time, it's watering too often in most cases as we should have proper sized containers and drainage. Have a read here.

Thread 'Watering, how media, pot size/shape and environment affect it' https://www.thcfarmer.com/threads/w...-size-shape-and-environment-affect-it.126852/

Typically no longer than a week to see a deficiency of any sort for any reason.

Watering issue is almost a certainty... lack of uptake means the plant cannot provide nutrients for proper photosynthesis.... deficiencies and pale growth with swollen leaves

Adding more cal mag or nutes will not help if the plants not able to uptake them.

Back the light way off... as should be done when encountering any deficiencies until remedied and give a proper wet dry cycle.

Just because a plant has a deficiency does not mean it needs more of that nutrient and 95%+ of the time it's environmental factors that are the root cause such as watering, PH, light, temp, humidity etc.
 
Mugwort

Mugwort

299
63
Hey so my two plants the leaves all seem to be turning a pale color and also yellowing from outside in with little burn on couple leaves but not much but they are a real pale almost pastel green kinda. Pics don’t really show exactly how they look. What would be causing this most likely? I am running one spider farmer sf4000 at the moment above the two plants about 24inches. Thought it might be light stress or something so I raised it yesterday to about 30inches above tops. The runoff on the first plant seemed to be in range around 6.3pH when I fed with nutrients yesterday pH to 6.5 although the one in back runoff was about 7 possibly higher…I used a chemical drop to test water. I fed each plant about a gallon of water. Two gallons mixed with fox farm trio big grow 6tsp, big bloom 6tsp, and 2 tsp of cal mag pH to 6.5. Haven’t looked at them since I watered them yesterday. Here are some pics. They have been in veg for a long while, longer then I ever have done. They sprouted from seed on 7/26/21 so it’s been like about 10 weeks from when they first emerged. They are gelat.og feminized. Originally had them in a 2x2x4 with one spider farmer sf1000 until they got way to crowded then I moved them into the 4x8 and am currently only running the one sf4000 that’s directly above them. Had pH issues due to someone else who is inexperienced watering them when I couldn’t be there with tap water. Which wouldn’t have been an issue cause first dozen times I tested tap pH it was steady 6.5-6.6 although I have since been testing and noticed it fluctuates in pH and sometimes is 7pH or higher. So I flushed both couple weeks back and things were good and seemed to help. Got runoff back to 6.3 range on both. Although that was before and now I need to figure out what the issue is now ASAP. Trimmed a lot of yellow discolored leaves off recently and they are all mostly looking the same now yellowing from outside edges and or just light pale color. I realize this is probably a lot and am probably rambling a bit but you guys have been awesome and I know if anyone can help me solve these issues it is this community, thanks 🙏 🙂
Dunno...maybe put out a few more pics.
 

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