4 weeks into flowering and fan leaves are yellowing and purpleing?

[Noonin NorCal]

We are 4 weeks into flowering daytime temps reach 75-80. and at night could get down to 58-60 degrees. I ran the strain in a greenhouse light dep it totally purpled out with warmer temps. It might look like a N deficiency but its yellowing and purpling at the same time, I tried googling it and maybe could be a phosphorus deficiency? Im in soil and only water every 4 days i let it completely dry out before waterings. The strain is Quantum Kush from TGA Subcool

 

[RoyalStone]

I had that happen with a diesel cut I used to have as well as my Celia og. I gave them about 1-2 cups less water than usual during their feelings and they would straighten themselves out in a week. I use soil with a fairly high N levels and water ever 3-5 days. It's usually no problem in the long run for me

 

[Noonin NorCal]

They are in 7 gallon containers and each gets close to a gallon. I know its a bit much but i let the soil completely dry. There is pretty much no run off, they are in plastic containers sitting on saucers. I have seen a few fliers, probably gnats, but its not that bad. The soil we get has all the amendments it says its good for upto 60 days without having to add anything, but i always added extra perlite and worm castings. Its North County Bounty 420 blend they use to call it, now its SO CO blend i believe

 

[RoyalStone]

You could also place potato slices in your pots to check if it is a gnat issue.

 

[GreenDream]

You're probably letting the soil dry out a little too far. This same thing would happen to us when we let the soil dry out to the point you are describing. Try watering just a little sooner and see if that doesn't rectify the situation

The first 2 waterings we let the soil dry out more, to get the roots to search, but after that we go to the slightly faster regimen. The plants have stayed greener since doing this. Do the lower leaves also fall off very easily when handled? That's another sign of too dry a medium.

 

[ganjygav]

I've caused no end of lockouts by letting my plants get too dry. It makes the soil go acidic. I've just got over a calcium def from this. All I did was water a bit sooner and increased the amount of water until I got run off. Now my soils ph is recovering.

Also my last crop when in the bin 4 weeks into flower. I had a massive fungus gnat infestation in some low quality soil I used. It started like yours, I noticed a few here and there. Then one morning I woke up and went to water and my soil was crawling with adult gnats. Hundreds of the little shits in each pot.
The plants were already sick so I just cut them down and started again.
Even if you only see a handful of adult gnats there could be lots more larvae in the soil eating ya thread roots. I had hardly any roots on my plants.

But your problem is probably a watering issue.

 

[justanotherbozo]

...yeah, i'm having a little trouble seeing what your problem is.

 

[ganjygav]

Yeah pictures always help lol

 

[Noonin NorCal]

You're probably letting the soil dry out a little too far. This same thing would happen to us when we let the soil dry out to the point you are describing. Try watering just a little sooner and see if that doesn't rectify the situation

The first 2 waterings we let the soil dry out more, to get the roots to search, but after that we go to the slightly faster regimen. The plants have stayed greener since doing this. Do the lower leaves also fall off very easily when handled? That's another sign of too dry a medium.

The leaves aren't falling off easily. Its weird i only have 5 plants in the room 2 are turning yellowish to purple. the one closest to the intake fan is slowly yellowing while turning purple at the same time. Im thinking maybe its getting blasted with to much cold air, the fan only comes on 6 times a day. I might try next time i water with nutes to throw a little Grow that has a bit more Nitrogen then the PK I've been adding

 

[Easy7]

Probably just low N and cold temps. Completely separate issues.

What are you feeding the plants at this point? There going to start drying up if they run completely out of N and that's not so pretty. A dose of N with there P & K would be ok. No bloom regime of mine ever completely eliminates nitrogen until flush.

 

[Noonin NorCal]

Im new at growing indoors with soil, we always had tables used rock wool and did ebb and flow. I water with nutes let it dry, then they get compost tea let it dry, then a flush, so i guess its like a 3 part watering? . all with filtered water, this time the third watering being a flush i added silica/ProTEKT. Last watering of Nutes got Liquid Karma which is only 0.1-01-0.5 NPK, Liquid KoolBloom which is 0-10-10, granulated KoolBloom which is 2-45-28. i also added some Boogie Brix mix. When i water with nutes its all at half dosage or so. The grow i use during Veg. is just a simple 2-1-1 Grow called Earth Juice and always added Liquid Karma. Its just weird to me the other 3 plants are green and lush, all soil and watering are the same

 

[Noonin NorCal]

I know pics would make this a lot easier, but I'm a complete noob when it comes to technology. Id have to upload pics from a phone, i don't have a workable camera

 

[Easy7]

Sounds highly likely that the soil is Nitrogen deficient. It's not going to catch up on nitrogen until time to harvest. Learn from this one. Flowering plants still require nitrogen. I only cut the N when I want to flush even if organic.

 

[Noonin NorCal]

Sounds highly likely that the soil is Nitrogen deficient. It's not going to catch up on nitrogen until time to harvest. Learn from this one. Flowering plants still require nitrogen. I only cut the N when I want to flush even if organic.

Yeah the more i look at them it does look like a Nitrogen problem, but they are coloring out like they are almost done, like a fall outdoor harvest. Tomorrow is 5 weeks and its a 60-65 day strain. Im gonna add that Grow nutrient next watering. Would that be ok with all the other nutes that i used in the last watering? Id also like to add some GOGNATS I've seen a few fliers, I'm not sure how. i let my soil dry out before every watering

 

[stonedfly]

.... Last watering of Nutes got Liquid Karma which is only 0.1-01-0.5 NPK, Liquid KoolBloom which is 0-10-10, granulated KoolBloom which is 2-45-28. i also added some Boogie Brix mix....

this mix of nutes sounds like a problem. just caught my eye dunno, maybe its mellow

 

[Noonin NorCal]

this mix of nutes sounds like a problem. just caught my eye dunno, maybe its mellow

IDK, everything outdoor last fall and my light dep runs. seem to like it. I like to keep it simple and we are old school don't PH anything, we simply use tap water for indoor but run it under bubblers for 4 -8 hours. All the outdoor light dep had a filter running from the hose

 

[Noonin NorCal]

I think its just me. Thinking everything over to much. I guess drinking lots of beers will do that.... Im gonna try and upload some pics

 

[stonedfly]

analyst paralysis is real my friend, lol

 

[GreenDream]

I'm tellin' ya.... I've been growing for almost 20 years, and for a long time I used to let my plants dry out too far. It's true that plants like wet and dry cycles, but if you're drying them out to where they can take over a gallon without runoff in that size container, you're probably letting them dry too far. It would make sense that the ones near the intake are showing it the worst, since the airflow can exacerbate the drying. I used to grow in saucers, so I got really good at judging how much water per container size to feed. In 7 gallon pots, when they were all the way dry, 1+ gallon would re-moisten with barely a drop of runoff. Once we hand-built drip tables (before the days of botanicare 4x8 tables) we started switching up our watering techniques, and found out that maintaining a slightly wetter grow medium was advantageous. Obviously we still let them go through wet/dry cycles, but we don't let them get quite as dry, and now shoot for about 10-15% runoff. I give 40 gallons to 42 7gal plants and get about 10-15% runoff. That ratio has been working VERY well. As you can see it's not a huge difference to what you are doing, but you might be surprised as to the difference it makes. It took me yearrrrs to figure this out. It seems so simple, but it can make all the difference in the world. All we did was start watering just a little sooner and the health of the plants increased surprisingly.

Another thing to look for.... if the medium is drying out too much, the nutrients will concentrate and the runoff will show higher EC and lower pH than the nutrients being put in. This is all due to the concentration effect of it getting too dry. Check your runoff and see if this is happening. This doesn't have to happen; it's just a potential sign. Just because it's not happening doesn't mean drying isn't the problem, if that makes sense. This indicator shows more prominently the heavier one is feeding. Light feeding regimens may not show this much at all.

Again, just trying to help, because when I read the amount of water and runoff you described in your first post it reminded me exactly of what we used to do before we dialed it in.

(edit): also, some nutrients are locked out when there's insufficient moisture.

 

[rockymountainJ]

I had similar issue due to ph, and lack of cal and magnesium in my local tap.... since I started ph'ing my water, and a little cal mag life's been good!! Cheers hope you get it figured out!!