Browning Leaves

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Hackerman

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Some of my Critical Kush clones are showing leaf browning. It's not on all plants and it's not on all leaves. Seems to be sporatic for now but I want to catch it before it spreads.

3 weeks into flowering. 3 qt pots (the smallest I have ever grown in). Watering every 3 or 4 days with Fox Farms trio and Cal-Mag.

These CK were real eaters when they were in 7 gallon pots but I think I over-nuted them for these tiny pots.

It looks like either nute burn or a real bad pH imbalance. I will measure the run off next time I water but I water with a 6.4 to 6.6 pH.

Everything else looks pretty good except that occasional burn.

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Hmmm, not good. I see some leaf tip burn which would make me think overnute, but I also see damage within the leaf in different locations. Necrotic patches in a couple of the pics would make me think there is a Phosphorous deficiency occurring, but the smaller spots look like calcium deficiency.

It has been my experience that when you have multiple issues showing up at once like this, it is either a pH problem or toxic buildup. So we begin with pH as that is easiest to solve. What are you feeding/watering with at the moment and what is the pH of your solutions? Are these in soil or soilless medium?
 
Well I just looked back at the top and answered some of my questions. If the pH is even close to right when you check it then it is toxicity. You need to flush them good then go back to feeding with bloom nutes once they dry out a little.
 
I think the pH is good. I will check the runoff next water but I think I over-nuted them.

The mothers ate like pigs. So, I followed the same pattern here not considering that the mothers were in 7 gallon pots and these are in 3 quart pots.

I don't think it's a deficiency simply because of the feeding schedule. They get a full dose of FF Big Bloom and Tiger Bloom. Plus, every other water, I use a bloom booster. Right now it is Open Sesame. Plus, they get a double dose of Cal-Mag every watering.

The soil is 1/2 Fox Farms Happy Frog and half sand/perlite/vermiculite.

These 3 quart pots are killing me. I should have transplanted them into the 2 gallon pots I usually use. I took one out and root growth was not overwhelming so I left them in the smaller pots. Mistake.

I am keeping my fingers crossed and just waiting. They won't need watered for a few more days so I'll use plain water for the next couple waterings and see how it goes.

Thanks
 
If you fed them hard then you definitely have a toxicity issue. The fox farms stuff is known for causing a lot of salt toxicity over time. I wouldn't use that much of calmag every watering either. The key to keeping plants in smaller pots is to feed less each time but feed more often.
I would flush them now and then feed them with half (or even 1/3) as much nutes and calmag but then feed them every time you water. That way there isn't too much "stuff" in the medium at one time to choke the plants, but feed them more often so that they don't get hungry. :)
 
They just got watered yesterday and they are still real wet. Should I wait for them to dry out before I flush them or should I flush them now?

Thanks
 
If they were mine Hackerman I would flush now to stop the damage, and maybe put a fan at dirt level to help speed up the drying.
 
I do have a fan on the pots to dry them out faster. I'll try to flush tomorrow.

Thanks
 
Flush right away. It won't hurt a thing. If you are concerned about overwatering then aerate the water ffor a couple hours first before flushing as that will oxygenate the water, which will help the roots not suffer from too much water. Don't wait to flush them as the chemical buildup is causing damage to the roots as well as the rest of the plant.
 
I may have somewhat of a problem flushing.

The plants are all sitting on the floor. The pots are not in pans. So, when I flush them, the water will run through and then sit on the floor until the plants soak it up again.

I'm sure that's not a good idea.

I could flush them and then soak of the water with towels.

I would be difficult to pick the plants up and put them over a sink as they are entwined in the SCROG.

I'll have to soak it up, I guess.

Thanks again.
 
This getting worse....and, extremely fast. I can see it spreading.

I flushed with about 10 gallons of water just now. The water was pH6.8-7.0 and the runoff was pH5.3 to 5.7.

I soaked up the runoff with towels and I have a fan blowing on the pots to dry them. I only have about 5 more gallons of water and I will do those later this afternoon when they dry a little.

I hope this doesn't stunt them too much. They are starting to produce a lot of trics and I don't imagine this is a good time for tragedy and stress.

Wish me luck.
 
Flushing will not hurt them. However, having toxicity issues will continue to show damage ffor a few more days before it stops spreading. You definitely don't want to allow the plants to soak up the water that just washed through or it will bring the chems back in that were washed out. That is why it is always best to have them sitting in some kind of catch trays or large pan of some sort as you never know when you will have to flush them. In fact, if you do synthetic nutrient growing, you should plan to flush them at least once throughout their lives. I always flush mine at about the halfway point so that I get out any build-up and start fresh with clean medium again.
 
the pH in your medium must be really low as the water going in was about 6.9 and coming out measured about 5.5, that means the medium must be lower still to pull the water down that much. Once they dry a bit, you can add back with just bloom nutrients and no calmag right away. Make sure your pH in your feeding solution is at 6.5 before adding it back to the plants and then in about a week you should see them level off and in another week they should show some improvement. However, being in fflower slows the response of the plants to repairing the vegetative structures as it is ffocused on building flowers. It may be slow to respond, but if the damage seems to level off then it should slowly come back to looking better.
 
Thanks loads, pal. I'll keep you updated.

Can't say thanks enough. :)
 
You're welcome :) I just hope you can get them back on the straight and narrow so that they will yield you some fat nuggets :) Not to mention, having problems is the way to really learn how to grow MJ and get it right as well as correct issues as they arise :)
 
Well, I learned several lessons this time. LOL

But, I am trying a lot of new things and with new techniques will come trial and error. Hopefully, not too much error. LOL

The condition is still getting worse but I think I will have it under control soon. I am going to flush them again tomorrow, Instead of soaking up water with towels (lesson number 1 LOL) I made a little plastic dish that I can set under each pot so I can actually empty the runoff into a bucket instead of towels. It will be a little tedious doing it one plant at a time but..... I have all day tomorrow. :)

There is good news in the chain. My Landrace Afghan mother looks absolutely beautiful at almost 8 weeks. I am going to clone her tomorrow if I get time.

Thanks again for all the help. I'll save you some nuggies. ;)
 
No need to pH flush water. You are not trying to feed the plant.
 
My water is about 6.9 or 7.0 so I didn't do anything to it. I figured the pH of the runoff was so low, it wouldn't hurt to water on the high end.

I just finished a 4 hour flush. What a PITA. I took each plant, one at a time and put a doperware tray under it. Then, I put a glass ashtray under the pot to keep it out of the water that ran off into the tray. Then, I sucked the water out of the tray with a turkey baster to make sure the pot was never in the water.

I ran about 15 gallons through them today. I hope all this water doesn't lead to root rot. I am going to let them dry out for 3 or 4 days and then flush one more time. Hopefully, that will put it back into line.

Whew! What a lesson. :)
 
Before you do a second flush, do something like a standard watering so that you get enough runoff to test the pH. If it is right or close to right, then make up some nutrient solution and aerate it for about 3 hours. Then after it has aerated, check and adjust the pH and then water the plants again. The extra watering will not be a problem as long as you aerate the water well.

Any time you have to flush soil or medium, always take some water and aerate it for several hours and then adjust the pH to where it should be then after the flush, pour this aerated water in until you get a little run off then allow it to dry out like normal to get back on the wet/dry schedule.
 

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