Can someone help me identify this problem please

This plant is grown in soil and just given the simple line of foxfarm plus calmag. All the other plants are getting the same everything and they are doing fine including three more of this same strain. Under LED lights starting 5th week after flip. I think this might be a cal mag deficiency but Im not sure. I will include a scan of the leaves that made me aware of this and then pictures of the plant. There isnt very many leaves like this but I dont know if this will get worse. Just fed and watered 3 days ago in 15 gallon pots. If I forgot any info please let me know. Thank you.View attachment Photo_2023-07-13_091837.jpg

This is the scan of the leaves

They look healthy, soldier on ... I wouldn't try to fix anything....

Derbud420 said:

They look healthy, soldier on ... I wouldn't try to fix anything....

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Thank you for your help. Did you see the scans of the leaves? Those rust spots and darkening centers? Does it need a little more of something than the rest perhaps or is it too much of something because the leaves on the others are all perfect. Sorry for worrying so much but this is usually the chapter in my grows where I run into issues and I dont want it to get out of hand.

Curious
Did you add any lime to your soil
Are you checking?changing PH?
Once I establish my base soil
I never check ph or try and adjust it

Herb & Suds said:

Curious
Did you add any lime to your soil
Are you checking?changing PH?
Once I establish my base soil
I never check ph or try and adjust it

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I do, to a 15 gallon pot I added about a half cup of powdered dolomite lime per pot. The PH of my soil the meter says between 5 and 5.5 on all the pots. I may have to raise the PH in the soil a little. Thank you for your reply

Herb & Suds said:

Curious
Did you add any lime to your soil
Are you checking?changing PH?
Once I establish my base soil
I never check ph or try and adjust it

Click to expand...

You know what I forgot to mention this grow I started adding a liquid sulfur supplement after doing some reading on other threads how sulfur helps with thiols and making the bud smell better and I saw someone show this stuff here so I tried it. Not a lot and Ive only used it in two waterings so far. Do you think maybe the liquid sulfur lowered the PH of the soil?

Marbobley said:

You know what I forgot to mention this grow I started adding a liquid sulfur supplement after doing some reading on other threads how sulfur helps with thiols and making the bud smell better and I saw someone show this stuff here so I tried it. Not a lot and Ive only used it in two waterings so far. Do you think maybe the liquid sulfur lowered the PH of the soil?

View attachment 5307920View attachment 5307921

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No clue
Does it lower ph in water?
I use a feed that already provides sulphur and a booster that does to
It looks like you cut back on nitrogen too
Like I said i don't PH in soil and any cheap meter I have seen for soil is worthless

I agree with Derbud- it looks like it may be a minor deficiency or excess nutrients- however I have found that if I remove the damaged leaves and monitor closely- the plant often gets better without changing anything drastically. Chasing small issues can lead to bigger issues if you are not careful and know exactly what the problem is.
It may just be a small hot spot in the soil from adding amendments.

Herb & Suds said:

No clue
Does it lower ph in water?
I use a feed that already provides sulphur and a booster that does to
It looks like you cut back on nitrogen too
Like I said i don't PH in soil and any cheap meter I have seen for soil is worthless

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Thank you. When you say looks like I cut back on nitrogen is that a bad thing? Should I give them more nitrogen? Im just following the foxfarm soil feeding schedule.

Bud man 43 said:

I agree with Derbud- it looks like it may be a minor deficiency or excess nutrients- however I have found that if I remove the damaged leaves and monitor closely- the plant often gets better without changing anything drastically. Chasing small issues can lead to bigger issues if you are not careful and know exactly what the problem is.
It may just be a small hot spot in the soil from adding amendments.

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I have taken the affected leaves off and I will see if it gets worse. Thank you for your reply.

Marbobley said:

You know what I forgot to mention this grow I started adding a liquid sulfur supplement after doing some reading on other threads how sulfur helps with thiols and making the bud smell better and I saw someone show this stuff here so I tried it. Not a lot and Ive only used it in two waterings so far. Do you think maybe the liquid sulfur lowered the PH of the soil?

View attachment 5307920View attachment 5307921

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What's the active ingredient because I'm thinking it could be Calcium Sulfate.

curious2garden said:

What's the active ingredient because I'm thinking it could be Calcium Sulfate.

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That must be what it is because its not saying anything as far as where its derived from. Using my soil ph meter I tested the soil outside in the tomato garden in the earth and the ph came back around 5.5. In my pots in my grow the ph goes to 5. Do you think just some dolomite lime on top before next watering should do the trick to bring up the ph of the soil or any other ideas?

5 is a little low but as others said above those cheap PH soil meters suck hogs. Measure the PH of the runoff and adjust accordingly. I would use around half to three quarters of a cup of pulverized lime mixed in the top and watered in.

Im not sure exactly what the browning in the leaves is but another thing could also be a severe gnat infestation in the soil and they are eating the shit out of your roots, ive seen similar not exact issues when I had severe fungus gnat infestation years back using cheap walmart manure. Good luck, keep us updated.

Again the soil ph tester is junk
Don’t rely on it
Dolomite lime needs time to break down in soil and is best used after being mixed in long before planting
Their aren’t many shortcuts

curious2garden said:

What's the active ingredient because I'm thinking it could be Calcium Sulfate.

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I wondered the same thing, and searched for info. I couldn't find a list of ingredients! The usage amount at 5 mL per gallon makes me believe it's has other calcium sources. You can only dissolve about 9 grams of calcium sulfate dihydrate per gallon, so if you want to supplement 100 PPM Ca, you'd have to use a lot more than 5 mL/gal. Scienceinhydroponics had a good article on its use.

Marbobley said:

That must be what it is because its not saying anything as far as where its derived from. Using my soil ph meter I tested the soil outside in the tomato garden in the earth and the ph came back around 5.5. In my pots in my grow the ph goes to 5. Do you think just some dolomite lime on top before next watering should do the trick to bring up the ph of the soil or any other ideas?

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That looks like an expensive form of Gypsum which is used as a Ca source and soil improvement but it can't raise pH so I'd be careful about giving multiple sources of Ca. I'm purely hydro, the only reason I know anything at all about this stuff is the amount of really good soil growers we have here for example:


Hope it helps and looking forward to hearing how it works out

curious2garden said:

That looks like an expensive form of Gypsum which is used as a Ca source and soil improvement but it can't raise pH so I'd be careful about giving multiple sources of Ca. I'm purely hydro, the only reason I know anything at all about this stuff is the amount of really good soil growers we have here for example:

Using Calcium sulfate during flower

Just an FYI We run Masterblend throughout. This grow we replaced half of the Cal Nit with Calcium Sulfate at week four of flower. They didn’t miss the extra N and look healthier than ever. I’m undecided whether to totally replace the CN with CS after week 6 , on this 10 week strain. The MB...

rollitup.org

Hope it helps and looking forward to hearing how it works out

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Thank you. That browning has now spread to almost all the leaves and they are getting crispy and falling off. The lower half of the leaves dont seem to be affected strangley, Im not sure whats going on. I watered last night with just plain water and dolomite lime. My water is high PH anyways so it should raise the PH a little in the soil. My water PH from the tap is 8.3-8.5, its tap water. The rest of the plants including the same strain as this one are doing great. Just this one is acting funny. Ill be harvesting in about 3 weeks so lets hope this one doesnt get too bad and can finish otherwise Ill just take it out of the tent and make more room for the others to spread out.

Do you think I can take a plant thats starting its 6th week after flip to 12/12 and bring it outside now in the Northeast and let it finish or will it go back to reveg? Thank you

Marbobley said:

.......snip..........
Do you think I can take a plant thats starting its 6th week after flip to 12/12 and bring it outside now in the Northeast and let it finish or will it go back to reveg? Thank you

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There are a lot of guys here from the Northeast I'm sure someone will be around to answer you. I grow indoor only. You could also do a search on here or check your day lengths there: https://www.timeanddate.com/sun/@5203634
Looks like you hit 12 hours around first part of September. So until then you might need light deprivation ie throw a tarp over it so you'd have to have an external structure around it to cover.

curious2garden said:

There are a lot of guys here from the Northeast I'm sure someone will be around to answer you. I grow indoor only. You could also do a search on here or check your day lengths there: https://www.timeanddate.com/sun/@5203634
Looks like you hit 12 hours around first part of September. So until then you might need light deprivation ie throw a tarp over it so you'd have to have an external structure around it to cover.

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Oh thats a good idea, I can put it in a dark shed at 5pm that should work. Ill make sure it well vented too, cause humidity and rain up this way has been horrendous lately. Thank you