420 Magazine Background

Help! Pale yellow leaves with brown spots

Emilya

Member of the Month: Mar 2019 - Grow Journal of the Month: Jan 2020, Aug 2021
I see you are a HAM. Me too!

Amateur Extra! Upgraded from Advanced about 5 years ago, very active in ARES and CERT here locally and a DX'er at heart. You know what they say about great minds! :)
 

Luckydawg

New Member
I'm back, just bought a ph meter with probe, which is telling me I'm at 7 ph at the top and bottom of the pot. My original match up of the symptoms with those diagnostic pictures brought me to manganese, not magnisium. The suggestion for this was folliar spray of any fert with that in it, which MG does have. I know lots of folks don't like this product, but I'm thinking this is an emergency, the girls don't look good.

I am going to flush with lots of water and add some nutes, (MG) as suggested by Fanleaf. Fingers crossed, can't think of what else to do.
 

fanleaf

Well-Known Member
Amateur Extra! Upgraded from Advanced about 5 years ago, very active in ARES and CERT here locally and a DX'er at heart. You know what they say about great minds! :)

Pretty much same here. Been very active in RACES and CERTS for the last several years. I need to fire up the HF rigs more often than I have lately but I just get busy from time to time. I always go through spurts of very active HF and then not so much but I'm on both VHF and UHF every day!
 

Emilya

Member of the Month: Mar 2019 - Grow Journal of the Month: Jan 2020, Aug 2021
let me add to the confusion by telling you that the soil pH is meaningless. From the moment that you water, the pH of the soil will begin to creep upward as the water and what is in it reacts to what is in your soil. Just make sure that every fluid that hits your plant, whether you spray it or dump it in the soil, and whether it has nutes in it or is just plain water, has been pH adjusted to 6.5 before you apply it. Don't worry about the soil, when you dump in 2/3 of the container size of properly pH'ed water to bring the soil to saturation, the pH takes care of itself.
 

fanleaf

Well-Known Member
I'm back, just bought a ph meter with probe, which is telling me I'm at 7 ph at the top and bottom of the pot. My original match up of the symptoms with those diagnostic pictures brought me to manganese, not magnisium. The suggestion for this was folliar spray of any fert with that in it, which MG does have. I know lots of folks don't like this product, but I'm thinking this is an emergency, the girls don't look good.

I am going to flush with lots of water and add some nutes, (MG) as suggested by Fanleaf. Fingers crossed, can't think of what else to do.

Did you tet that with the soil soaking wet? It will always read 7 if not.
 

fanleaf

Well-Known Member
let me add to the confusion by telling you that the soil pH is meaningless. From the moment that you water, the pH of the soil will begin to creep upward as the water and what is in it reacts to what is in your soil. Just make sure that every fluid that hits your plant, whether you spray it or dump it in the soil, and whether it has nutes in it or is just plain water, has been pH adjusted to 6.5 before you apply it. Don't worry about the soil, when you dump in 2/3 of the container size of properly pH'ed water to bring the soil to saturation, the pH takes care of itself.

LMAO. Let me add further to this by disagreeing with some of this. Soil ph is NOT meaningless at all. That defies every farmer across the world of everything grown. Soil will not always stay in good ph range for cannabis. For instance peat moss in soil can break down and make the soil very very acidic and lockout every nutrient fed to a plant. If the ph of the soil were meaningless things would be grown perfectly by everyone all of the time.

100% organics are slightly different than other grows but I don't think that's what we are dealing with here.
 

Luckydawg

New Member
BTW, this was an organic soil and i've tried to stay organic with FF nutes and such in flower. Not sure what to do about lowering the ph if this is the problem as Emilya suggests. Also, I'm using tap water.
 

Emilya

Member of the Month: Mar 2019 - Grow Journal of the Month: Jan 2020, Aug 2021
LMAO. Let me add further to this by disagreeing with some of this. Soil ph is NOT meaningless at all. That defies every farmer across the world of everything grown. Soil will not always stay in good ph range for cannabis. For instance peat moss in soil can break down and make the soil very very acidic and lockout every nutrient fed to a plant. If the ph of the soil were meaningless things would be grown perfectly by everyone all of the time.

100% organics are slightly different than other grows but I don't think that's what we are dealing with here.

please let me restate... because you are 100% correct, the pH is very important. What I should have said is that any measurement of soil pH at any particular moment in time is meaningless, because it is a moving target. Adjust the fluid each time, and the soil pH has no choice but to follow.
 

fanleaf

Well-Known Member
BTW, this was an organic soil and i've tried to stay organic with FF nutes and such in flower. Not sure what to do about lowering the ph if this is the problem as Emilya suggests. Also, I'm using tap water.

FF only has 1 nutrient that is all organic and that's Big Bloom. The rest are organic and synthetics.
 

fanleaf

Well-Known Member
please let me restate... because you are 100% correct, the pH is very important. What I should have said is that any measurement of soil pH at any particular moment in time is meaningless, because it is a moving target. Adjust the fluid each time, and the soil pH has no choice but to follow.

Agreed 100% except the
Adjust the fluid each time, and the soil pH has no choice but to follow.
If the soil is wanting to be at 5.8 because if whatever like peat moss decay you can add all of the 6.5 water/nutes you want and the ph may show 6.5 for a few hours until the peat takes back over again. Then your straight back to 5.8
 

Luckydawg

New Member
After flushing with tap water, and adding weak solution of MG fert, I retested ph and its says just below 7???? Any comments, of should I just wait now and see what happens. In the meantime, i'll research how to drop the ph just a tad in any new water I apply. And thank you both again for the suggestions so far. Without this kind of forum it would really be impossible to hash this out.
 

Emilya

Member of the Month: Mar 2019 - Grow Journal of the Month: Jan 2020, Aug 2021
Talking about growing organically often times starts fights in the growing community. For me, organic means no bottled anything, and I will be using nothing but water during my entire grow. I can do this because I added all that the plant can possibly need, as I mixed up the soil. (subcool's recipe) and the only way my plants can get these nutrients is for the living things in that soil/compost mix to break down the organic material into its component elements. I take great care to keep my soil that is waiting to be used, alive, and after cooking for several months this soil has everything in it that the plants could possibly need. Organic for me means a bit more than simply not being synthetic.
 

fanleaf

Well-Known Member
So if I understand the confusion properly, what I am measuring with my new meter is the ph of the water I just used.

If you are sticking probes in the soil then only to a small degree. Your soil will change the ph of the water you just added. If your soil is wet right now test it now and again in a few hours and again 8 hours later. You will see the buffering effect of soil.
 

Emilya

Member of the Month: Mar 2019 - Grow Journal of the Month: Jan 2020, Aug 2021
After flushing with tap water, and adding weak solution of MG fert, I retested ph and its says just below 7???? Any comments, of should I just wait now and see what happens. In the meantime, i'll research how to drop the ph just a tad in any new water I apply. And thank you both again for the suggestions so far. Without this kind of forum it would really be impossible to hash this out.

yes, adjust the water before you apply it... every time. Adjust to 6.5... every time. Adjusting the water is easy.. from the grocery store you can use vinegar for pH down, and pickling lime for pH up. If you want to go stronger and get out of food product additives (that could attract bugs) I use lye to create a diluted pH up (store in glass only) and I use a diluted 15:1 distilled water/battery acid solution as my pH down. A box of battery acid that will last you a couple of years, will cost you about $6... same with the lye.
 

fanleaf

Well-Known Member
After flushing with tap water, and adding weak solution of MG fert, I retested ph and its says just below 7???? Any comments, of should I just wait now and see what happens. In the meantime, i'll research how to drop the ph just a tad in any new water I apply. And thank you both again for the suggestions so far. Without this kind of forum it would really be impossible to hash this out.

If it's just below 7 then leave it right where it is!!!!!!!!!!! WAIT!!!!!!! She will improve, you watch and see. Give her time now. Hope you flushed plenty.
 

fanleaf

Well-Known Member
After flushing with tap water, and adding weak solution of MG fert, I retested ph and its says just below 7???? Any comments, of should I just wait now and see what happens. In the meantime, i'll research how to drop the ph just a tad in any new water I apply. And thank you both again for the suggestions so far. Without this kind of forum it would really be impossible to hash this out.

My tap water is unusable even with ph down. My tap comes out at 8.2 and and 290ppm TDS. When I add ph down (even sulfuric acid) to set ph at 6.8 it all looks great until I let the water sit for 6-8 hours then it's straight back at 8.2. I'll ph down 5 times to 6.8 and it goes straight back to 8.2!

My water is buffered at 8.2 and won't move until treated about 6 times! GARBAGE
 
Top Bottom