Can't seem to figure this out

I have 4 plants in their 5th week of flower and can’t figure out why the leaves are yellowing in the middle of the plant, turning brown and dying. This just started occurring 1.5 weeks ago. I water every 2 days with nutes added once a week. PH runoff is 6.5, ppm 850, using 1000 W HPS 12/12 18-20" from canopy, 72-74 degrees, 25-44% Humidity, 500 ppm co2, adequate cfm air displacement.

They are all in 3 gallon smart pots with Happy Frog amended with 1.5 cups Dolomite Lime, 1.5 cups Bone Meal & .5 cups Blood Meal per 2 cubic feet.

Through veg used 2ml BioBizz Grow and 1ml Mammoth per gallon of tap water that sits for 48 hours

So far through flower used 2 ml BioBizz Grow, 10ml BioBizz Flower & 1.5ml Mammoth P per gallon of tap water that sits 48 hours

Here is what I have tried so far

· Upped grow nutes 6 weeks ago to 4ml but saw N burn so stayed at 2ml
· Added Alaska fish fert 1 week ago – No difference
· 1 week ago, had some fungus gnats so watered wit h 3% h2o2 and water mixed 1 part to 4 part – No difference and gnats are gone
· Yesterday bought 5 gallon smart pots and added 4 inches of the amended soil then placed the 3 gallon pots inside packing the edges with soil – Results unknown yet
· Yesterday did a cal mag foliar spray - Results unknown yet


My suspicion is that the Bone Meal is just now breaking down the P so with the bloom nutes, it’s too much.

I’ve posted pics (HPS is on) for you all to look at and perhaps offer me some advice. Right now I am considering flushing but with the Bone Meal in the soil I am not sure if this is wise.

Any and all ideas are much appreciated.

Get a picture with hps off, makes the diagnosis harder to tell.

hibok said:

Get a picture with hps off, makes the diagnosis harder to tell.

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You bet. Lights go out in 20 minutes then I'll head in and take pics with incandescent

Looks a lot like phos. Def maybe it's being taken in being lockedout for some reason when did ya add a good pk boost

Of it gets to cold in ur tent or room it will make it a lot harder for plants to uptake phosphorous what's ur temps lights out ?

I zoomed in on pic better the Brown spots on leaves look also like a potassium problem.maybe a magnese prob do u check ph and all that ?

Justinsbudzzz said:

Looks a lot like phos. Def maybe it's being taken in being lockedout for some reason when did ya add a good pk boost

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Can't imagine def since there is bone meal in the soil and the bloom nutes has a 2 value. I've never used a P/K booster but certainly will if a P def is the consensus.

Justinsbudzzz said:

Of it gets to cold in ur tent or room it will make it a lot harder for plants to uptake phosphorous what's ur temps lights out ?

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mtnman2016 said:

Can't imagine def since there is bone meal in the soil and the bloom nutes has a 2 value. I've never used a P/K booster but certainly will if a P def is the consensus.

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Temps are 74-76 lights on, 72 off. PH is 6.5 in runoff.

Took new pics with HPS off and updated the main main post.

Justinsbudzzz said:

Do u ph or u going for a organic buffer itself type grow

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Organic buffer via the Dolomite Lime. I have a soil PH meter that shows 7.8 PH (I don't rely on these type meters), runoff shows 6.5 on my digital meter, the tap water is 7.0
I should add I have a 5th plant same age but was stunted early on in a 5 gallon smart pot under a 315 CMH that is not exhibiting any issues at all. That is why I put the 3 gallon pots in 5's with extra soil thinking maybe a root bound issue.

mtnman2016 said:

I have 4 plants in their 5th week of flower and can’t figure out why the leaves are yellowing in the middle of the plant, turning brown and dying. This just started occurring 1.5 weeks ago. I water every 2 days with nutes added once a week. PH runoff is 6.5, ppm 850, using 1000 W HPS 12/12 18-20" from canopy, 72-74 degrees, 25-44% Humidity, 500 ppm co2, adequate cfm air displacement.

They are all in 3 gallon smart pots with Happy Frog amended with 1.5 cups Dolomite Lime, 1.5 cups Bone Meal & .5 cups Blood Meal per 2 cubic feet.

Through veg used 2ml BioBizz Grow and 1ml Mammoth per gallon of tap water that sits for 48 hours

So far through flower used 2 ml BioBizz Grow, 10ml BioBizz Flower & 1.5ml Mammoth P per gallon of tap water that sits 48 hours

Here is what I have tried so far

· Upped grow nutes 6 weeks ago to 4ml but saw N burn so stayed at 2ml
· Added Alaska fish fert 1 week ago – No difference
· 1 week ago, had some fungus gnats so watered wit h 3% h2o2 and water mixed 1 part to 4 part – No difference and gnats are gone
· Yesterday bought 5 gallon smart pots and added 4 inches of the amended soil then placed the 3 gallon pots inside packing the edges with soil – Results unknown yet
· Yesterday did a cal mag foliar spray - Results unknown yet


My suspicion is that the Bone Meal is just now breaking down the P so with the bloom nutes, it’s too much.

I’ve posted pics (HPS is on) for you all to look at and perhaps offer me some advice. Right now I am considering flushing but with the Bone Meal in the soil I am not sure if this is wise.

Any and all ideas are much appreciated.

View attachment 4279166 View attachment 4279168

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Looking at those pics I'd say K def.

The tip burning and curling, where the chlorosis starts (at end), the spots, all are telltale signs. I also didn't see anything very high in K for your nutes unless I missed it. It could be multiple things, but looking at those pics I'd wager K is one of your main issues. K is more important than P for cannabis.

I didn't realize you were at wk5 and looking at the zoomed out version I'd say give it some potash and not to re-pot.

If your tap water is hard and has lots of bicarbonates, its probably precipitating some of the available K out, on top of your plant using what amount of K is being supplied in the first place. Just a guess.

You may still have some root tip issues from the gnat, which is in turn effecting uptake of everything, but from those pics, I'd say it's wanting K. I'd pick the shitty leaves off to make light more available to the other leaves that can use it better.

Nitrogen and magnesium??

The cal mag would be my guess.

Are they the furthest away from the light??

Just a few observations and things to consider:

Firstly, your plants look pretty good all things considered. Many here would like to have your problem of trying to get such nice plants to the finish line. Looks like you'll have a nice harvest regardless.

So you started with Happy Frog (a relatively balanced and complete soil)...then you added 24 TBS of Lime...which was probably at least 8 TBS too much and most likely more so than that. When you did this you drove your pH down. If your soil was sitting at 6.5 pH, you didn't help it with the addition of the lime. I would venture to say you added more Bone Meal than you needed to as well and I would say you're correct in noting that the bone meal is probably only now beginning to break down. Then you added additional Nitrogen by the addition of the Blood meal. At this point I'd say your soil has enough in it, provided the plant can get it.

Then you add into the mix the BioBizz...not hating on you, but I am so unimpressed with this company's site and the information they provide; which is almost nothing. Never the less, you're now feeding with this on top of an already charged soil.

The addition of the Biobizz equates to Biogrow 3:0:7 and BioBloom 1:2:2

Then you added Fish Emulsion: 5:1:1

Then you added a CalMag foliar feed: 2:0:0

With all this being said, I fail to see where the plant would be short on anything in terms of what's in the soil. I think your issue is an uptake issue, not so much that the nutrients aren't there. I noticed you're testing your runoff pH, but you don't mention testing your water / feed pH. I realize you're in soil and in theory the water / feed pH shouldn't matter, but it's where I'd begin, regardless of what your runoff may or may not be telling you. Consequently, when you tested your runoff for ppm and pH was this after a feed or after a water only? Have you done both to see what the differences are?

Regardless your plants look pretty decent. I would refrain from throwing any more kitchen sinks at them, considering where they are in their lives. I hate the idea of any foliar spray during flower, but if you feel you're short on a specific element, it might be best to foliar spray it vs. feeding it via the soil....again though I would refrain if it were me.

I wish I could be of more help or just say "hey, do this or that", but we all know it rarely works out that way. It's obvious you know what you're doing for the most part. I would just try to breathe easy, relax and get your girls to the end without doing anything unnecessary. Good luck friend.

BTW, I've been down this rabbit hole myself, back when I said "I do" to organic soil grows. Thankfully I divorced that B' for a nappy headed chic on the street corner named 'Coco'...she's been my girl ever since.

mtnman2016 said:

They are all in 3 gallon smart pots with Happy Frog amended with 1.5 cups Dolomite Lime, 1.5 cups Bone Meal & .5 cups Blood Meal per 2 cubic feet.

Through veg used 2ml BioBizz Grow and 1ml Mammoth per gallon of tap water that sits for 48 hours

So far through flower used 2 ml BioBizz Grow, 10ml BioBizz Flower & 1.5ml Mammoth P per gallon of tap water that sits 48 hours

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CannaCountry said:

So you started with Happy Frog (a relatively balanced and complete soil)...

The addition of the Biobizz equates to Biogrow 3:0:7 and BioBloom 1:2:2

Then you added Fish Emulsion: 5:1:1

Then you added a CalMag foliar feed: 2:0:0

With all this being said, I fail to see where the plant would be short on anything in terms of what's in the soil. I think your issue is an uptake issue, not so much that the nutrients aren't there.

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4 - 3 - 6...

2 - 7 - 4...


These were the products I was referring too, maybe you can give some insight @mtnman2016 ...

Bone meal has ZERO K. Blood meal gas very little K. Fish emulsion has no K. If the biobizz products I was looking at were the right ones, the ratio of 10ml : 2ml still looks lacking in K considering cannabis' demands. Couldn't find an NPK of happy frog.

Water in some potash and if it gets worse you know you're locking out your manganese, but I bet it looks better.

Look here for the Mn symptoms I was referring too as well as K...


This is where I was talking about excess K blocking Mn...


These are all just ideas, so do whatever the fuck you wanna do (if you are familiar with the Hodge twins, that's how I'm saying it) , good luck

But am curious as to what the npk's of your biobizz products are...

CannaCountry said:

Just a few observations and things to consider:

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I am with you 100% on my application of amendments as well as my choice in nutes. I experimented with the same combo last grow on one plant and was very impressed by the initial growth but I now recall I had this same thing happen during flower and forgot to put the info in my journal. I used Roots Organic with HF and no amendments the last couple of years successfully but wanted to try something new and while not a resounding success, I learned a lot (more on that below).

ChiefRunningPhist said:

But am curious as to what the npk's of your biobizz products are...

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BioBizz NPK values are as follows.
BioGrow (3-0-
BioBloom (1-2-2)


Worst leaves have been removed. For the final 2 feedings before flush I am going to maintain the nutes as before, PH to 6.2 and add some K to 1 plant one feeding to see if there are any changes out of curiosity and will post final results/thoughts.

I want to thank all of you for replying to my post and taking the time to go into such detail around your thoughts and diagnostic steps. I love learning this stuff and appreciate you passing on some of your knowledge. I won't be using amendments in soil again unless it is made specifically for the entire grow without nutes. It's way too hard to evaluate feeding issues when using both. Next grow is Coco Coir with Canna Coco nutrients and 1 plant in DWC to start learning hydro.

Quick update on the issues I encountered. Last night I found my soil test kit and took samples from 2 plants, 3-4 inches down as well as a sample from the roots of a male I chopped down 4 weeks ago. The indications show a depleted/deficient P & K. N is spot on and PH is 6.7 in the soil. I am very cautious when it comes to nutes after bad results in Ocean Forest and following a schedule so I am using a bit over half the recommended feeding once a week and will increase to 75 then 100% the last 2 feedings.

I got my hands on a couple Purple Monkey Balls starts a few days ago and will be moving them from soil to coco coir and biting the bullet on an RO system. I tried this particular strain last year and it was #3, maybe even #2 in my top ten favorites for taste & effect. Since it is my first coco grow, I will be cloning them for the run and if it turns out good I plan to make some tissue cultures for future grows.

Happy growing everyone. Peace.