Leaves curling with a bronze area down the middle

[Sooperdooper]

Hello my plant has recently started to turn yellow pretty quick, I'm having some leaves with bronze in the center that are also folding or curling. I had some burn early but flushed and reduced feeding and all was well. I'm growing in biobizz light mix with biobizz nutrients. I pH the water to about 6.2 when I water. My runoff pH has been pretty high though (around 7.5) although ec was around 600 ppm with 100 ppm water. What kind of problem does this look like? It looks pretty bad to me, so I'm hoping to start fixing it quick, thanks for the help!

 

[013]

I see no mention of cal-mag, both calcium and magnesium are essential to the plant and the large majority of nutes address the NPK but not the cal-mag. Do you have cal-mag on hand?

Also your runoff ph or ppm are of no consequence - worry about your inputs not the output. Chemical salts and fine sediments come out in the wash - so it’s automatically a skewed number. Often times new growers measure runoff ph or ppm and then start adjusting inputs to get a different value in the runoff, don’t chase that rabbit - it leads nowhere good.

as always - don’t jump now but see what other replies come in

 

[Sooperdooper]

I see no mention of cal-mag, both calcium and magnesium are essential to the plant and the large majority of nutes address the NPK but not the cal-mag. Do you have cal-mag on hand?

Also your runoff ph or ppm are of no consequence - worry about your inputs not the output. Chemical salts and fine sediments come out in the wash - so it’s automatically a skewed number. Often times new growers measure runoff ph or ppm and then start adjusting inputs to get a different value in the runoff, don’t chase that rabbit - it leads nowhere good.

as always - don’t jump now but see what other replies come in

Sorry I didn't mention cal mag but that's one of the biobizz nutrients I'm currently using. Does it look like a cal mag problem?

 

[013]

Partially but if you’ve been using cal-mag regularly then should be ok, but I try to start with low hanging fruit. Its got some deficiency going but also pulling nutes from lowers.

Snip a few leaves and scope them front and back, the shiny leaves kinda resembles mites. Do you have jewelers loupe or pocket microscope? If not try smartphone app called magnifyer. Some mites can be seen with naked eye, others can’t but using scope on leaf undersides often reveals their eggs.

I’m just a newbie but I’m going to ask MOTM winner @BeanTownFan420 to jump in, really skilled grower with keen eye!

 

[Sooperdooper]

Partially but if you’ve been using cal-mag regularly then should be ok, but I try to start with low hanging fruit. Its got some deficiency going but also pulling nutes from lowers.

Snip a few leaves and scope them front and back, the shiny leaves kinda resembles mites. Do you have jewelers loupe or pocket microscope? If not try smartphone app called magnifyer. Some mites can be seen with naked eye, others can’t but using scope on leaf undersides often reveals their eggs.

I’m just a newbie but I’m going to ask MOTM winner @BeanTownFan420 to jump in, really skilled grower with keen eye!

I wouldn't think I have a mite problem at the moment but I honestly don't know, I use d.earth and a leaf spray thats supposed to prevent that. I also don't have the same issue with any other plants in the tent (I have 4 others)

 

[Emilya Green]

I see signs of both magnesium and phosphorus deficiencies here.

Hello my plant has recently started to turn yellow pretty quick, I'm having some leaves with bronze in the center that are also folding or curling. I had some burn early but flushed and reduced feeding and all was well. I'm growing in biobizz light mix with biobizz nutrients. I pH the water to about 6.2 when I water. My runoff pH has been pretty high though (around 7.5) although ec was around 600 ppm with 100 ppm water. What kind of problem does this look like? It looks pretty bad to me, so I'm hoping to start fixing it quick, thanks for the help!

I believe that your pH is fine, as long as you are pH adjusting the final fluids that hit your soil, not pH adjusting the water before you add anything to it. Runoff pH is meaningless in a soil grow and the value you get is arbitrary, much based on the amount of runoff you let come out, ie, the dilution of the mix. Don't make any decisions based on this measurement, just make sure your incoming fluids all are adjusted to 6.2 pH.

I think what has happened is that you have misread your situation as a burn and reduced your nutes, when that was exactly the opposite thing that you needed to do. I believe that due to a lack of mycorrhizae development in your soil your phosphorus pickup was light anyway, but now with reduced nutes and a flush, the situation got worse.

My advice is to increase your nutes back up to regular levels and double check how you are adjusting pH, and I think the green will come back in to many of your leaves that have not gone too far, once you have made the adjustments

 

[Billpopy79]

I've done a few grows using the biobizz range in the light mix soil.
Every single time I got a magnesium deficiency around 2 weeks into flower.

As Emilya says above, make sure you ph after mixing nutes.
Myself I added a teaspoon of Epsom salts to the water around week 5 along with a small amount of the topmax which I believe is molasses based.

Also I found using the recommended amount of grow/fishmix after the first few weeks of flower was too nitrogen heavy finding it better to slowly taper it down after the initial stretch in flower. I'm assuming their 4ml/l is for growing oak trees.

 

[Sooperdooper]

I see signs of both magnesium and phosphorus deficiencies here.

I believe that your pH is fine, as long as you are pH adjusting the final fluids that hit your soil, not pH adjusting the water before you add anything to it. Runoff pH is meaningless in a soil grow and the value you get is arbitrary, much based on the amount of runoff you let come out, ie, the dilution of the mix. Don't make any decisions based on this measurement, just make sure your incoming fluids all are adjusted to 6.2 pH.

I think what has happened is that you have misread your situation as a burn and reduced your nutes, when that was exactly the opposite thing that you needed to do. I believe that due to a lack of mycorrhizae development in your soil your phosphorus pickup was light anyway, but now with reduced nutes and a flush, the situation got worse.

My advice is to increase your nutes back up to regular levels and double check how you are adjusting pH, and I think the green will come back in to many of your leaves that have not gone too far, once you have made the adjustments

Thanks for the response! I'll definitely pick up the nutrients, is it problematic if I let the soil dry out too much between watering?

 

[Emilya Green]

Thanks for the response! I'll definitely pick up the nutrients, is it problematic if I let the soil dry out too much between watering?

not at all... that is the only way you can draw oxygen down to the very bottom roots. It also helps to keep away populations of fungus gnats, who love moisture. Most people try to dry their soil out completely between waterings while in veg, just to build more roots... and then when in bloom they try to use those roots to get as much water and nutes as they can into the plant, not ever letting the soil dry out as completely, pushing water at the plants as fast as they can take it. I still however, stop this practice about every third watering in bloom, and I let them dry out to the point that I can see lower leaves starting to droop. I consider this occasional drought stressor to be very good for my plants and I can see that giving the roots that hit of oxygen provides for a mini growth spurt afterwards.