Mg Deficiency? (Photo)

Is this indicative of magnesium deficiency? about 5 weeks into flowering and this only appears on a few middle leaves so far. thanks.

I've dealt w/mid-level yellowing 4-5 wks in and stopped mine by flushing well, the last flush containing 1 tbl-gal AlaskanFish 5-1-1 and full bloom nute dose. I generally only use 1/2 dose flowering nutes, so you may (perhaps?) double your normal bloom nutes instead?
Stopped the yellowing and took care of N needs for remainder of grow.

i've been giving them daily diluted doses of 3-20-20 maxsea bloom with watering, small amount of molasses, small amount of epsom salt, and every other day supplement with 0-50-30 monster bloom. thinking i may flush them for a day or two.

problem is only occurring on my sour D, not on the kush plant.

so i went ahead and checked the soil ph and my water ph, both near 6.8 or so. I was concerned that it might be nute lockout but that doesn't appear to be the case. Then i thought it might be nute burn, but the plant is almost 4 feet tall and i don't even give them full strength nutes. As for the Mg deficiency, i've been giving my plants a pretty steady low-dose of epsom salts for a while now. I don't think it's a fungus because the humidity is fairly low, probably 40-50% max. finally, i just leeched the soil a few minutes ago and gave it a fresh dose of nutrients and epsom salt, so we'll see what happens.

as for the leaf in the photo above, it turned about half brown and i cut it off. Other leaves near it are starting to exhibit the same brown spots and yellowing, although not to the same extent. i'm beginning to wonder if it's a calcium deficiency. i guess i'll wait and see tomorrow if it improves.

the plant itself is about 36 days into flowering and has already produced numerous fairly large buds. if the condition worsens, will i be able to save the buds? also, anyone have any ideas as to what my issue is? some of the leaves are starting to twist, too, but otherwise the plant looks quite healthy. i can add more photos if that would help.

so it looks like it's starting to spread upwards. it was only the fan leaves and it looks like some of the bud leaves are now affected. the leaves are also starting to turn kind of purple, or at least darker, and those with the brown spots are discoloring to yellow a little bit. here are some more photos of the progression. the buds are quite large now and look just fine, with about 20% amber hairs.

i'm afraid whatever this is is starting to envelop my plant. it probably has at least 3 more weeks to go and it would be a shame for it to die.

as stated above, i leeched the soil, gave it fresh nutes, continued giving it some epsom salt, confirmed proper ph, and so on, but nothing seems to work.

strangely enough, the kush plant right next to it receives the same exact nutrients and everything else, and is the same size, and is perfectly green and is producing amazing buds.

please, if you have any ideas for me, i'd appreciate it. i've put a lot of effort into this plant to get it to bloom as well as it has so far, and would hate to lose my entire yield.

thanks.

edit: on day 37 or so of flowering. sour diesel is the strain, though may be a hybrid (bagseed from sour diesel sack, may have been pollinated by another strain).

milfordcubicle said:

so it looks like it's starting to spread upwards. it was only the fan leaves and it looks like some of the bud leaves are now affected. the leaves are also starting to turn kind of purple, or at least darker, and those with the brown spots are discoloring to yellow a little bit. here are some more photos of the progression. the buds are quite large now and look just fine, with about 20% amber hairs.

i'm afraid whatever this is is starting to envelop my plant. it probably has at least 3 more weeks to go and it would be a shame for it to die.

as stated above, i leeched the soil, gave it fresh nutes, continued giving it some epsom salt, confirmed proper ph, and so on, but nothing seems to work.

strangely enough, the kush plant right next to it receives the same exact nutrients and everything else, and is the same size, and is perfectly green and is producing amazing buds.

please, if you have any ideas for me, i'd appreciate it. i've put a lot of effort into this plant to get it to bloom as well as it has so far, and would hate to lose my entire yield.

thanks.

edit: on day 37 or so of flowering. sour diesel is the strain, though may be a hybrid (bagseed from sour diesel sack, may have been pollinated by another strain).

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could be a P lockout. it's hard to use too much calcium, but if you do it can cause this lockout. or you could just be deficient in P as wel or your ph could be off. issues like this on new growth are often related to such things i'm pretty sure. note i am referring to the "burnt and rusty" looking symptoms, not the normal fade from week 4-5

yes ik this is like a decade old but in case anyone else comes here, based off pics they saw, to diagnosing their issue i figured i would try and answer.

What is your PH? I would look to that first

Your first pic is indicative of a Ca shortage; perhaps locked out, perhaps non existent. The fact that it shows on one strain and not the other isn't uncommon. Different plants want / need different requirements. Whatever you do, don't think it will fix itself over night and in fact it may be too far along to affect much at all without sending yourself down a rabbit hole. I would look at what you're feeding, determine how much Ca is in your feed and then make a logical choice in terms of adding some. If you think you have plenty of Ca in your feed, then look at your pH or an over abundance of another element that is locking out the Ca. Whatever you do, don't sweat it, you'll make it to harvest.

CannaCountry said:

Your first pic is indicative of a Ca shortage; perhaps locked out, perhaps non existent. The fact that it shows on one strain and not the other isn't uncommon. Different plants want / need different requirements. Whatever you do, don't think it will fix itself over night and in fact it may be too far along to affect much at all without sending yourself down a rabbit hole. I would look at what you're feeding, determine how much Ca is in your feed and then make a logical choice in terms of adding some. If you think you have plenty of Ca in your feed, then look at your pH or an over abundance of another element that is locking out the Ca. Whatever you do, don't sweat it, you'll make it to harvest.

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lol i re-activated a 10 year old thread it seems. it could def be calcium deficiency after i went back to read he was using epsom salts not cal/mag. that said calcium deficiency usually start mid finger on the leaf. calcium excess usually starts at the finger tip on a leaf. both look very similar with the addition excess calcium also locks out MG and P and your plants will eventually look like nute burn. i would say you may be right about calcium deficiency given his feedign regiment.
persinalyl i wouldnt use epsom salt like he is, but if he insists on epsom salt he needs to dissolve egg shells in vinegar like i do. this becomes soluble calcium. just mix it into your watering. i don't use epsom tho for MG i use langbenite as it also has allot of sulfur, which imo is responsible for a stronger smell. i beleieve this is why terpinator does what it does. it is derived from sulfates