spotting diagnosis

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Bogart Mc Thunderdunk

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hey so first day of flower day 69~ overall. ive got brown spots on a few leaves on my white siberian photo. im no good at diagnosis so if someone would tell me what they think this ould be that would be great.
ph seems stable around 6.5 maybe a touch lower if anything but not much, im using ph'd tap water and have no ppm/ec meter,
nutes im using are gh 3 part flora feeding at around 1.3x strength of the guidlines of the drain to waste on the GH site.

from troubleshoots and some pictures it seems like it could be calcium, manganese or potasium but as i said im bad at that.

temps stable around 77f lights on 68off
600watt hps

there are also light tips on some leaves but im pretty sure thats from hitting off some t5s a while back though maybe not.
this plant had similar spots as a seedling.
i have garden lime, canna mono magnesium 7% MgO, various nutes, epsom salts, pk 13/14 seaweed and lots of other random stuff. ill order something if needed.

see sig for more details if needed or i should be on all night anyway.
any help appreciated.
cheers

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It doesn't look too serious. Could you have splashed some nutrient solution on the leaves when watering?
 
hey thg,
yeh i just like to catch things early, especially since i had a rough start with these.
possibly splashed but i always try to water basically touching the soil.
i am active on another forum and have been recommended to up the micro a bit to add more calcium, any thoughts?

its on a few different leaves over the same plant, mostly on well developed fans none on new growth.
 
I found that I always needed to use Cal-Mag with GH 3-part Flora series during flowering. I would say that if you believe you have a calcium deficiency (I am also not good at diagnosing nute problems) that Cal-mag may be a better choice than upping the micro nutes.
 
good to know its not just me so, yeh im gonna order some to have as it seems like a common problem solver, something to add to the cupboard anyway. no chance of getting it locally though so till delivery atleast id say ill just add some micro for that plant.
cheers anyway
 
I would agree with using the cal/mag. Calcium is what I am thinking, although it looks to be early enough that if it doesn't take too long to get the calmag you should be ok. :)
 
i had the same exact problem during veg before i bought my ppm meter. the necrosis would come on slowly and gradually get worse and worse(but very slowly). i was also following the feeding chart on my nutes. it turns out that i had a ppm of 1450+ which is wayyyy too much for a dwc system. yours is flood and drain, so a slightly higher ppm is normal b/c your roots dont sit in the solution 24/7. but if your doing 1.3X strength, maybe when you fed them your ppm was really high and the nutes caused lock out like mine did...ppm meter saved my plants
 
I have got to disagreed shortbus. I have had many, many strains that I run with ppms in the 1500+ range in DWC. I do not believe this is necessarily too high. Also, nute burn starts as a crisping of the tips of the leaves and not as individual spots on the leaves. I really see no sign of nute burn on these plants and do not believe that high ppms is the cause of the spotting, but rather a deficiency of some kind, most likely a Cal-Mag thing.
 
cheers for the confirmations, im growing in soil if i didnt mention that though. in 2.7~gallon pots(little small...) could this have something to do with it? just not getting enough feed/rootbound?
plants are lst'd but not much i just kinda corkscrewed them around a quarter turn if that makes sense. tallest is 16" shortest probably 12"(most stretchy strain apparently) so they wont be huge overall. think this will be enough to get them through the grow? ive read a gallon per foot of height as a basic guidline but i know that doesnt take overall size/width into account

im apprehensive about repotting again with all the trouble i have had with ph and soil. i cannot find anything decent around here and if i can i cant tell untill ive bought and used it as everything is vague "good soil for things!" kinda explanations, no details. might be too late as is anyway. any thoughts? last one i bought was fine on ph but solidifies like rock when watered even with like 20% perlite. a good airy soil i think was the vague description on that one:angrywife:

i would prefer to stay in these and deal with watering more often etc. if atall possible.

ill order the cal/mag tommorrow havent been able to till then, for now i gave a slightly higher micro portion todays feed.
when is foliar feeding ok till? i know im prettymuch still in veg im just curious or can you give calmag in liquid form mixed in with a feed? is that just too slow..

cheers dan hopefully i can keep them like that. i noticed something else weird on another plant today but had no camera and had to leave for a weekend of work. looked like either nute burn on the tips of the serrations of the leaf but not the actual tip of the leaf. only one leaf overall i could see and nothing drastic just a mm or two. ill have a good look sunday late/monday might be back for that.
 
I would think keeping them in those pots should be fine unless they have already been in them for a couple months in veg. You may have to feed them more often rather than more nutes at one time. The brown spots on the serrated edge of the leaf sounds like a progression of magnesium deficiency. They don't look terrible so don't paniic. I would say to get the liquid cal/mag and add it in at feeding, should correct the issue (the necrosis that you see now will most likely not go away as it is permenant damage, but you should see less and less new necrosis popping up going forward). Get the cal/mag asap but foliar feeding is not necessary at this point.

You can foliar feed any time you don't have buds. But you have to be careful with it as it can cause problems if not used correctly. :)
 
ok cool just checking it wasnt related.
i have canna monomagnesium MgO 7%. would this be any use till calmag arrives? it will take about a week and ill have a feed due within that time.

also (possibly misinfo) i hear unsulphured molasses and epsom salts can be used as a DIY calmag. i have both of these things is all. any truth to that? or better to wait it out.
 
I am not sure about the monomagnesium but I believe you are correct about the molasses and epsom salt. The only problem with those is that they are not chelated and I don't know how long it will take for them to become available to the plants. The liquid calmag is already chelated and is available to the plants as soon as it hits the soil. I am afraid to tell you to use the unchelated nutes as you could possibly over-do it with both.
 
ah never thought of that. good stuff ill hold off but i may add a ml or 2 of that magnesium next feed if i havent received the calmag yet unless someone advises against it anyway. seems like itd help to me.

this is the problem leaf on the sour ak that might be magnesium. just incase its not, if not overfert?
attachment.php

just one leaf on the whole plant so far.

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Ya know those leaves are pretty dark green, which is a prewarning that they are getting too much nutrient and are getting ready to burn. However, that necrosis on the edges of the leaf are not nute-burn. Nute burn almost always begins at the tips of the leaves as if someone has taken a hot iron or lighter and turned the very tips crispy and brown. That is according to my MJ problem solver, a calcium deficiency beginning. So getting the calmag juice will be the fix. I am in coco/hydro and that requires constant addition of cal/mag solution because the coco tends to absorb it and hold it. I have found that by using the cal/mag solution(10ml per 10-15liters of water) whenever I add water to my rez. Being in soil as you are, I would say to add 15ml on the next watering when you get it, then 10ml on the next watering, then 5ml every watering after that until they finish.

I wouldn't use the other stuff on this run since you will be using the liquid. I would say that you can add that stuff into the soil that you make up for the next run as it will take some time for it to become available to the plants. And just keep the liquid for emergencies or for adding in toward the end of a grow when the soil ammendments have been used up by the plant. :) I wouldn't worry about adding anything until the liquid cal/mag comes in as that could complicate things. Unless you find out that it is going to take longer than 7-10 days to get it. If that is the case then go ahead and add in the other stuff with the next watering.
 
cool, about the dark green thats not really like that in person just i have to use the flash to not get a blurry real colour version as my hands arent the steadiest, and that makes it seem that way. theyre much more normal in person even a little too light.

cheers for the info ill get on it soon as it arrives.
:aok:
 
ok so finally received the calmag just one question by 15 ml do you mean per plant or per gallon etc? guessing per plant?
they only take about a gallon each anyway so i suppose it doesnt matter too much.

details on this say calcium magnesium supplement,
dtpa chelated iron
edta chelated zinc

the ratio on the bottle is 6-8-0-0

ill be feeding tonight.

plants havent really gotten any worse no new marks but im sure theyre just hanging on the edge of it anyway.
good growth with first budsites starting to form.
 
15 ml per gallon of water to fix problems occuring now, and 5 ml to keep the problems away. I would agree with HP when he said to step it down from 15 ml to 10 ml to 5 ml per gallon of water with each watering for better results.
 
i use a tbl spoon of cal mag/gallon all the way through flower, every grow jmo
 

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