Question about MANGANESE(Mn) def?

Snow Crash

Snow Crash

Well-Known Member
That's either a calcium deficiency or the result of foliar feeding. The spots are small and dark; spread throughout the entire plant rather than located at the tips or filling spaces between veins. This all points to calcium deficiency. If the spots were lighter and more uniform then you'd be looking at a magnesium deficiency. Mn is in really low demand in cannabis, especially compared to calcium. The dark color of the leaves indicates to me that Nitrogen is very available. If the pH of the soil is beneath 6.5 then this reinforces the chance it is a calcium problem. Also, tap water that hasn't been allowed to breathe has a strong chance of carrying chlorides and fluorides in it, which can electrically bind up calcium to make calcium chloride and calcium fluoride salts.
 
carokann

carokann

Active Member
Look for small, grouped, whitish spots on the top surfaces of leaves. Spider mites will tap into the bottom of a leaf to extract the juice, and this causes spots topside
 
Carl Spackler

Carl Spackler

Well-Known Member
Here is a sure-fire way to detect spider mites on any plant material that I learned a few decades ago when I first learned pest-management on ornamentals. Take a sheet of white,typing paper, hold it underneath whatever plant you suspect has an infestation and simply shake the plant thorougly back and forth for a few seconds. If mites are present, you should be able to see them moving around against the white background easily. If you are long-in-the-tooth like me and require bifocals just to get around you can simply take the palm of your hand and smear the paper gently. This will crush the bodies of the mites and leave reddish or rust colored streaks that reveal their presence. There are also hundreds if not thousands of threads on this site with pictures of cannabis with infestations of spider mites that can be used as a reference. I've been fighting these little guys since before many posters on this site were having solid bowel movements so I know the tell-tale damage when I see it and this isn't it. Period.
On to the actual problem. Since this is at day 73 of flower, chances are that even if you are able to correct the micro-deficiency it will be too late to make a significant difference in yield or quality of the flowers. The Jack's ratios (20-20-20) are fairly high in macros and, even diluted down to say a 10-10-10 or less so it could be a bit dicey for a foliar application but may be worth a shot. Choose a plant that appears to be more affected by the problem and spray the diluted solution on a few fan leaves and wait several days to determine efficacy. In the future you might be a little less heavy-handed with the use Epsom Salts as it can lead to a Mn deficiency but, it is rare with higher quality potting soils.
 
robbzilla

robbzilla

Well-Known Member
OZUT said:
I just checked for you with my scope and I can see the spider mites in your picture...

But seriously, if you think you can see spider mites without a scope and because you can't see one then you're realllllyyyy in for a surprise...By your own admission you've never seen a spider mite and never had a problem with them so what makes you think you don't have them? Won't hurt to check it out bro...Just saying....

If you think you've narrowed it down to a deficiency and you can't foliar feed them, then just completely flush your plants with final phase or clearex and give them a complete fertilizer solution to bring things back to normal....The more you fuck around with trying to raise levels of certain elements, the more you're gonna fuck your shit up...

Also, you (spider) mite have fixed your deficiency and (spider) mite not be seeing the results because your leaves are fucked up beyond repair....Pluck the ones that are 50% damaged and see what happens in a day or so...

Hope that (spider) mite have helped
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Thank you for you suggestion.
I said I have never had spider mites not that I have never seen a spider mite.


Snow Crash said:
That's either a calcium deficiency or the result of foliar feeding. The spots are small and dark; spread throughout the entire plant rather than located at the tips or filling spaces between veins. This all points to calcium deficiency. If the spots were lighter and more uniform then you'd be looking at a magnesium deficiency. Mn is in really low demand in cannabis, especially compared to calcium. The dark color of the leaves indicates to me that Nitrogen is very available. If the pH of the soil is beneath 6.5 then this reinforces the chance it is a calcium problem. Also, tap water that hasn't been allowed to breathe has a strong chance of carrying chlorides and fluorides in it, which can electrically bind up calcium to make calcium chloride and calcium fluoride salts.
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I was thinking cal def too when the problem first started and I also considered mag def. I am still leaning towards a combo of maybe cal and Ph flux because I keep reading how rare it is to have a Mn def. I ordered some cal-mag that should be getting here today. The only thing about trying to raise the cal levels is that it is also going to raise my mag levels and if it is actually Mn def than raising the mag level with just make the problem worse.

I'm kind of in a spot here.....

Carl Spackler said:
Here is a sure-fire way to detect spider mites on any plant material that I learned a few decades ago when I first learned pest-management on ornamentals. Take a sheet of white,typing paper, hold it underneath whatever plant you suspect has an infestation and simply shake the plant thorougly back and forth for a few seconds. If mites are present, you should be able to see them moving around against the white background easily. If you are long-in-the-tooth like me and require bifocals just to get around you can simply take the palm of your hand and smear the paper gently. This will crush the bodies of the mites and leave reddish or rust colored streaks that reveal their presence. There are also hundreds if not thousands of threads on this site with pictures of cannabis with infestations of spider mites that can be used as a reference. I've been fighting these little guys since before many posters on this site were having solid bowel movements so I know the tell-tale damage when I see it and this isn't it. Period.
On to the actual problem. Since this is at day 73 of flower, chances are that even if you are able to correct the micro-deficiency it will be too late to make a significant difference in yield or quality of the flowers. The Jack's ratios (20-20-20) are fairly high in macros and, even diluted down to say a 10-10-10 or less so it could be a bit dicey for a foliar application but may be worth a shot. Choose a plant that appears to be more affected by the problem and spray the diluted solution on a few fan leaves and wait several days to determine efficacy. In the future you might be a little less heavy-handed with the use Epsom Salts as it can lead to a Mn deficiency but, it is rare with higher quality potting soils.
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Ya Im going to try the white paper tech you talked about once my girls wake up. I'm with you though, I'm like 99% sure its not spider mites.

On to the the actual problem like you said. They are acutally only 29 days into flowering and 73 days since seed. I only have 2 plants growing anyways and only one is showing the Mn def. Being that you say its dicey to foliar feed with jacks I just dont want to take the chance. I mean the damage is really localized to the top couple of leaves right around the bud sites. Its not much at all. Well at least not yet. I must admit it is slowly getting worse but it just doesnt seem to be spreading all that much.

You think that if I water with ferts that only have Mn and no Mg for awhile that might help? Or you think I should foliar feed?

Ya I know it was my first flush with epsom salt and I think I did go a little heavy. Live and learn though.
 
carokann

carokann

Active Member
hey buddy sorry i thought those were mites. its calcium def. for cheap fix crush soak and strain eggshells then use the water.
 
G

gobbly

Well-Known Member
"Manganese (Mn) deficiency is much more common that most growers realize, but fortunatley, the symptons are very distinctive and easy to recognize. Symptons appear at the top of the plant and all growing shoots. Older leaves seldon show any signs. Symptons begin as chlorosis or a bleached blotching of tissue starting at the base of the leaf where the blades join. As the condition progresses, the interveinal tissue turns pale green to yellow or white, but the veigns remain dark green or pale green. The telltale sign for Mn, as distinguished from Fe or Zn deficiency, is the margins of the affected leaves remain dark green, so that each affected leaf is outlined with dark green, but all the inner tissue between the veignsturns yellow or white." ... "Mn deficiencies seriously affect good flower formation. MAturation is delayed, and flower development is noticeably slowed and inhibited. Buds may be 12 weeks old, and still look immature." ... "Once that you know your plants have a dficiency of Mn, limit the amount of Fe and P in fertilizer, since both elements interfere with Mn utilization."

"Miracle-gro for tomatoes has every nutrient except B and Mo; Miracid is another good foliar treatment for Fe, Mn, and Zn problems."

That is a quote from Mel Frank. Hope it helps!
 
F

fredflinstoner

Member
IMG00038-20100720-1903.jpgIMG00039-20100720-1904.jpgIMG00042-20100720-1906.jpgIMG00036-20100720-1903.jpgIMG00037-20100720-1903.jpgCan someone please help me diagIMG00040-20100720-1904.jpgnose what is causing my leaves on my plant to get yellow and fall off? I am attaching pics to help you see the problem

IMG00041-20100720-1905.jpgCan someone help me diagnose my problem? I have yellowing leaves as well as spots as you will see from my pics
 
robbzilla

robbzilla

Well-Known Member
carokann said:
hey buddy sorry i thought those were mites. its calcium def. for cheap fix crush soak and strain eggshells then use the water.
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Its cool man no worries. I admit I did get a little testie with you earlier but I'm just sure it wasnt spider mites. I'm almost leaning towards Ca def now rather that Mn def after doing even MORE research. I can't really stop looking at the plants and comparing photos to the two different def. I mean Mn and Ca look so much alike its really hard to tell the difference between the two.

And like I was saying I'm really in a spot. I mean do I add more Cal-Mag and possible lock up more Mn? Or do I go with staright Mn fert with no Ca and Mg in it and possibly make the Ca def worse? Idk what to do really.
 
robbzilla

robbzilla

Well-Known Member
fredflinstoner said:
View attachment 1056128View attachment 1056127View attachment 1056126View attachment 1056125View attachment 1056124Can someone please help me diagView attachment 1056123nose what is causing my leaves on my plant to get yellow and fall off? I am attaching pics to help you see the problem

View attachment 1056122Can someone help me diagnose my problem? I have yellowing leaves as well as spots as you will see from my pics
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Looks to me to be either Nitrogen def or a Ph flux....
 
robbzilla

robbzilla

Well-Known Member
gobbly said:
"Manganese (Mn) deficiency is much more common that most growers realize, but fortunatley, the symptons are very distinctive and easy to recognize. Symptons appear at the top of the plant and all growing shoots. Older leaves seldon show any signs. Symptons begin as chlorosis or a bleached blotching of tissue starting at the base of the leaf where the blades join. As the condition progresses, the interveinal tissue turns pale green to yellow or white, but the veigns remain dark green or pale green. The telltale sign for Mn, as distinguished from Fe or Zn deficiency, is the margins of the affected leaves remain dark green, so that each affected leaf is outlined with dark green, but all the inner tissue between the veignsturns yellow or white." ... "Mn deficiencies seriously affect good flower formation. MAturation is delayed, and flower development is noticeably slowed and inhibited. Buds may be 12 weeks old, and still look immature." ... "Once that you know your plants have a dficiency of Mn, limit the amount of Fe and P in fertilizer, since both elements interfere with Mn utilization."

"Miracle-gro for tomatoes has every nutrient except B and Mo; Miracid is another good foliar treatment for Fe, Mn, and Zn problems."

That is a quote from Mel Frank. Hope it helps!
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Yea I've gone to the Mel Frank book a couple times but the only thing is I'm not having any paling or yellowing at all. I mean none of the leaves are white or anything, its really just those brown spots and they are localized on the tip top fan leaves right next to the buds almost. I mean the brown spots are on some older growth (fan leaves), but its not much at all. I still don't know which it is honestly. I think it is Mn and today I watered with some Jacks classic all purpose that only has Mn and no MG (which can lock up Mn) to see if it would improve any.
As I said I cant really foliar feed because I don't want to have bud mold or anything so I am seeing if this might help out. Any other suggestions?
 
I

ilcattivo

Active Member
Will you please post in this thread if you ever get this problem 100% fixed...I have it on 1 of my 2 plants. I went through exactly the same thing as you. 1st epsom salts, then cal, then Manganese....nothing helped. I had a little success with flushing, but never really got it nailed. I'd like to know what the real deal is if it ever happens to me again.
 
G

gobbly

Well-Known Member
calcium sounds like a good diagnosis. I had something kinda similar (though I think it was cal and mag), I corrected PH and dosed some mag/i/cal and it cleared up. Damaged leaves never recovered, but new growth was find from then on.
 
robbzilla

robbzilla

Well-Known Member
ilcattivo said:
Will you please post in this thread if you ever get this problem 100% fixed...I have it on 1 of my 2 plants. I went through exactly the same thing as you. 1st epsom salts, then cal, then Manganese....nothing helped. I had a little success with flushing, but never really got it nailed. I'd like to know what the real deal is if it ever happens to me again.
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Yes I will post if Ifind a solution. Like I said today I watered with fert only containing Mn and on my other plant I watered with only Cal-Mag fert so I am going to see which one helps I guess. I'll def keep you guys updated though.

carokann said:
i dunno if you have seen this http://www.icmag.com/ic/showthread.php?t=11688 but on the page is a picture of your leaves and it is calcium deficiency
View attachment 1056371
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Ya bro I've def seen that pic about 10 times. I mean but if you look at 10 pics of cal def and look at 10 pics of Mn def they really all look the same. I mean mag def almost looks the same for that matter. The only thing I can really tell that is different between ca and mn def is if you look closely at ca def you can see the yellowing on the leaves too. It seems to me from reading/research you dont get that little bit of yellowing when you have Mn def. But than again the yellowing could be a whole another prob with dudes plant (the plant in the pic that is). Idk man.....
Got any other ideas?

gobbly said:
calcium sounds like a good diagnosis. I had something kinda similar (though I think it was cal and mag), I corrected PH and dosed some mag/i/cal and it cleared up. Damaged leaves never recovered, but new growth was find from then on.
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Ya I feel you man. Like I was saying I was kind of leaning more towards Mn def and the start of the day and now I kind of fallen back on the ca def. But I got some good PHed water and like I said above did one plant with Mn fert and one with Ca-Mag fert. I just still don't know if I should foliar feed???
 
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