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Wonderland Grow


Well-Known Member
An excess of calcium blocks the uptake of potassium and magnesium (manganese too), so that's a possibility. Something @Emilya mentioned in another thread is that too high or low of a pH could cause nutrient uptake problems as well. She recommends varying the pH between limits.

Magnesium deficiencies take four to six week to show up, so that's on the table. So is an excess of calcium.

Can you remind us of the pH, substrate, and nutrient concentrations you are using? That should help identify the culprit.
Sure, I'm trying to be as detailed as I can.
My soil is Plagron LightMix. It's a quality substrate with the following characteristics:
Peat moss, perlite.
pH (H2O) 6 - 7
EC (mS/cm) 0,7 - 1,1
NPK fertiliser (12-14-24)

It does have perlite mixed in it, but I added more, 5l into 25l of soil.

My tapwater is normally 7.0+ pH. I don't have a ph pen, only ph strips and a liquid hydroponic ph kit, so I can only guess, but it should be around 7.4 based on the amount of vinegar I have to add to bring it down to 6.7. With the same amount added once more, it brings the water down to around 6.0, so that's where my guess comes from.
I varied the ph of the water pretty much. Not really on purpose, but since these kits rely on color, I can't be that precise every time. I usually aim for 6.5. Sometimes it lands around there, other times the strip is darker than it should be on 6.5, so I add more vinegar, and end up around 5.9-6.1. In the first ~2 weeks I didn't ph my water, then I bought the strips and ph-d it every watering.
Yearly water reports for every household are not a thing here, but I requested it from the water department, they had info on the particular area of the city where I live. They reported that my tapwater is between 510-550ppm, with 23-26mg/l of Mg and 85-90mg/l of Ca in it. As I mentioned in the post above, I always used tapwater, sometimes with nutrients added, sometimes only pure tapwater.

I have to admit, feeding was a bit inconsistent. I didn't add any nutrient to her in the first two weeks, when she was a seedling. Then after that, which was about 5 weeks ago, I started fertilizing. Unfortunately, I haven't really kept notes (apart from this journal) about feeding, but I mostly remember what I've done. In these 5 weeks, I watered her 7 (or probably 8) times, from which only 2 times was only tapwater, on the other occasions, I mixed in some nutes. I go exclusively with the BioBizz line, it's 100% organic, and it was pretty expensive. I bought the smallest available bottles, and the whole package cost me around 50-55$.
Here's what I have, with NPK numbers:
BioGrow: 4-3-6
It's a Dutch sugar beet extract, I used it almost every feeding (I believe there was only one time, when I used FishMix, and haven't added any BioGrow). Usually 2-3ml/l went into the mix.
FishMix: 5-1-4
Quite similar sugar beet extract with extra fish emulsion. The first two feedings, I used only BioGrow, since then I used both together. Similarly, 2-3ml/l when mixing.
BioBloom: 2-7-4
Used it twice, last two feedings. I was pretty light with it, only added about 1-1.5ml/l if I'm not mistaken, but one time I was quite drunk in the morning, while watering. :rolleyes:
TopMax: 0.1-0.01-0.1
It's a stimulant with humic and fulvic acids, meant to be used during flowering. Only mixed it in last feeding, 2ml/l.
AlgAMic: 0.1-0.1-0.1
A cold pressed seaweed extract. Apart from the first two feedings, I used it every time, and I was pretty generous, usually added 4-5ml/l to the mix. I also used it twice as a foliar spray.
Another additive, an aloe vera extract. I don't have an NPK value for this one. BioBizz claims,
Acti·Vera has been designed to protect the immune system, increase metabolism and enhance nutrient absorption in all sorts of plants.
I don't know if it does anything beneficial though, or it's just good marketing. Due to it's disgusting smell, I used it only one time for feeding and another time as a foliar spray, and put it away since then.

The recommended amount is 4-5ml/l of every of these nutes and additives.

Understand that calcium is usually considered a macro and at times is the second most used nutrient. Most cannabis strains have an insatiable need for calcium.
Good to know, Penny!
Now, as I dug up another thread, that I posted before I started this grow @TorturedSoul and @farside05 also mentioned something about it:
Calcium seems to be the second most important element after nitrogen to cannabis plants (and to plants in general; they probably use more of it than they do phosphorous).
Check this POST. Start around the 10 minute mark (although all of it is good). Calcium was #1. I hadn't listened to it all in a while. I thought N was #1 also, but it's #4. It goes Calcium, Potassium, Silicon, then Nitrogen.
Today I took a day off from work, I'm going to flush with ionised water now. When I'm done I'll do more research on deficiencies, but right now I feel like it might be magnesium.

Thank you guys for all of your help so far!:green_heart:
If anyone has thoughts about this issue and a solution for it, feel free to share it!

Old Salt

Member of the Year: 2019 - Member of the Month: Apr, Nov 2019
I use Jorge Cervantes' "Cannabis Nutrient Defficiencies & Excesses." You can Google and download it. Before checking nutrients, I look to the environment, temperature, humidity, light, and water including its pH. Many problems, if not most are environmental, and plants respond rather quickly when they are corrected. In the case of over watering soil it can take longer as we need to wait for the soil to dry out. Nutrient problems, especially like those that take time to show themselves, can take much longer for the plant to respond.


Member of the Month: Aug 2019
Hope you get it figured out Alice-I'm confident that you will !


Well-Known Member
Good luck rooting this problem out @AliceGG
Hope you get it figured out Alice-I'm confident that you will !
Thank you guys. :love:
I use Jorge Cervantes' "Cannabis Nutrient Defficiencies & Excesses." You can Google and download it. Before checking nutrients, I look to the environment, temperature, humidity, light, and water including its pH. Many problems, if not most are environmental, and plants respond rather quickly when they are corrected. In the case of over watering soil it can take longer as we need to wait for the soil to dry out. Nutrient problems, especially like those that take time to show themselves, can take much longer for the plant to respond.
Well, I thought about environmental factors a lot. I don't think there's anything extreme, to be honest. Temperatures are between 23-25°C (73-77°F). Humidity fluctuates, but not a lot. It was around 50% in the last two weeks. Sometimes it dropped to the lower 40s, and when I hang my clothes to dry (which I do in the room where my tent is) it goes up in the upper 50s.
Ph of the water, as I mentioned a few posts earlier, is likely fine. I only had 4l of ionised water at home yesterday, which wasn't enough to fully flush the plant, but I bought 15l more, so I'll finally flush it, and check the ph of the runoff. However, I don't really know what I should do with the info on ph of the runoff, once I got it... :D It's just something I haven't ever checked yet, so it might worth doing it once.

I found this picture from Jorge Cervantes:

Honestly, it only helped as much as anything else, which is not a much so far. I dug up the whole internet, a lot of growing sites, blogs, guides, symptom checkers. The problem is, a lot of these deficiencies seem very similar to each other. For example, just read what this picture says about phosphorus excess, then what it says about about potassium excess. It's almost literally the same! :D

One thing that is becoming more and more suspect for me is phosphorus deficiency. What are you guys think about it?
Though the symptoms don't exactly meet what's described as P def, they don't exactly meet anything else either. I don't know how much P a plant needs, but the two nutrients which were given in the largest quantities (BioGrow and FishMix) are both vegetative nutes primarily with low phosphorus content.

I took new photos, tried to finetune the camera settings for correct color display.

Here the whole plant.
I noticed that it stretched a lot in the last few days. Look at how tall the main stem is growing. I read that it can signal potassium def. But it can also be just natural stretching before buds are forming, who knows...

This is the top cola from above.
I don't see any strange discoloration, spots or anything. What I see is burnt and curling tips. It is not caused by the light, because new leaves on much lower branches curl upside down too.

See the lower branches here. Leaftips are curling.
One of the affected leaves are right in the middle of the bottom of this pic.

This one:


Probably this photo below shows the most accurate colors. I pulled the left side of the leaf out from the shade to take the photos, but as seen here and on other photos as well, the affected parts are which get direct light. The left leaflet shows much less discoloration and spots, and that's the one which was shaded by another leaf.
From growweedeasy.com:
Calcium deficiencies most often show up in the following places:
  • Newer growth (upper leaves)
  • Parts of fan leaves that have been exposed to the light
But then on other sites it is clearly stated that calcium def would show up on newer growth first.

And this is the worst looking right now.

Apart from curling upside down, I see these kind of tipburns on mostly every new leaves:

I thoroughly inspected the whole plant before I took the photos. The brown spots are only on the two leaves pictured above. There is one more between those two that shows a kind of discoloration, but there are no spots in it yet. I found two other tiny little brown spots on two other older leaves too.

This is what I got so far.


Member of the Year: 2017 - Member of the Month: Mar & Oct 2017, Aug 2018, May 2019 - Plant of the Month: Aug 2017


Well-Known Member
Ok, Penny, since you are one of those members here who knows the most about cannabis cultivation, my best bet is to take what you say. I thought about potassium too, but there are these two things that have set me back a bit:
1. I gave plenty of nutes which contain potassium. Now, after thinking about it more, I realized that it doesn't actually mean that I gave enough. Maybe this particular phenotype requires a lot more. So yes, this point might be invalid.
2. Although almost all the symptoms can easily signal potassium def, there's one I see everywhere but not on my plant. As i watch photos of K def on the internet, most of them show leaves that turn brown at the edges. The edges of these leaves on my AK actually look kind of fine. It's the internal sections between the veins that show the brown spots.

But now, as I've read a few pages about potassium def again, stretching and stem purpling (which I forgot to mention before) are two clear signs.
Unless it's a rarely occuring micro nutrient deficiency (like iron or zinc) it must be magnesium or potassium then. Since I came to this conclusion, here's what my plan is. Please, correct me if I'm wrong.
I will flush with ionised water till runoff. On charts, I can see that an excess of nitrogen, magnesium or sodium can lock out potassium. Basically, the only magnesium source was my tapwater so far, so I will feed with ionised water (not containing Mg), mixing in something that is relatively low in N and high in K (I don't even know what sodium is, so I can't care much about it now :D). Looking at my nutes, FixhMix is a no-no for now with an NPK of 5-1-4. BioGrow seems a bit better with 4-3-6, but what I mostly want to use is BioBloom, it's 2-7-4. Although the grow nute has a higher number of K than the bloom, the N:K ratio is better with the latter. I think I might go half grow, half bloom, 2-2ml/l of them. Does that sound right?
After a few days I should see results, I believe. If it's not K, then "depriving" magnesium with ionised water might make symptoms worse, and then at least I know it's very likely magnesium def.


Well-Known Member
I've just watched this video:

At around 2:05, he says

...this is what makes potassium deficiency a tough one, at least up to this point. But then a telltale sign appears: a strange type of leaf burning that's unique to potassium deficiency. Unlike nutrient burn, which starts at the very tips of fanleaves, and then advances, potassium deficiency burn hits several of the leaf margins at once. Burning the leaf aggressively from several directions at once along its edges as seen in these pictures. From this point on, you can be pretty sure you got the deficiency narrowed down to potassium.

So yea, I'm still unsure.
I flushed her, checked the ph of the runoff. It was about 6.5, just like what went in, I'm guessing it's fine. Now that she only got ionised water, if it's magnesium, it should make things worse, right? I'm leaving home in about an hour, coming back tomorrow, so my plants will be alone for about 30-36 hours. I'm very curious what I'll see when I come back.
I decided I won't feed her now, as it really affected only two leaves so far, so it can't be that bad yet. The two other leaves that only have a very small brown spot on them will show if it's getting worse.


Grow Journal of the Month: Dec 2017
@bobrown14 Very well said.
I wrote that?? musta been a good day with good weed.
Trying to make that every day.

Song quote:

"You know you're being good
When you start to feel it coming on
It's the eternal answer to the question
It's the strength that makes you strong

Everyday we feel the love" JP


Grow Journal of the Month: Dec 2017
Calcium is usually newer leaves, when i see older leaves with necrotic spots I’m thinking potassium
This ^^^ and I usually dont worry. Not all the plants have it.

You'd have to have that specific strain dialed in to make a call to actually do something positive. Anything else is a guess.

I have a plant right now with necrosis only on the largest fan leaves about like you have there. A few spots. All the other growth is perfect. I'm letting it go its course. My experience is that they will turn yellow and fall off in a week or so.

They give up the nutrients stored in the leaf back to the plant to begin the reproductive cycle. Let it grow. You will be fine.

Tasty nugz iz coming.


Well-Known Member
My trip took a bit longer than I thought, it was a bit more than 2 days. Well, I'm finally back.
Let's see the good and the bad news.

Although I only had a few minutes before the light went out, I inspected the AK as much as I could. The brown spots and yellowing didn't spread too much. I will have to carry out a more thorough visual inspection in the evening, but I didn't see a single one affected leaf so far, that's good news. I took off the worst looking one, just to see it in natural light, made a few pictures too, I'll upload them later.

Now, for the bad news. When I left on Friday (and, to be honest, already weeks ago too) I saw flying things... like miniature flies. There were only like 2 or 3 of them, and at this time of the year I see them elsewhere around the house too, so I didn't care too much. But now I'm a bit worried. I've just noticed a slowly moving brownish bug on the very top of my plant, walking on a leaf. I caught it with my hand, and put in under a glass. Now I have him trapped, still alive. I watched videos of bugs too, it might be a spider mite, but it doesn't exactly look like that. The legs are totally not as seen on pictures about spider mites, they are very short, not spider-like. But the bug itself is very small (about a milimeter), and its color is somewhere between red and black. Without a good macrolens, I can't really make a good picture, my phone also doesn't have a chance for this size.
I think the ones that I saw flying were other species, they were more like fruit flies, vinegar flies or midges. These are what I found in the translator. As far as I could see while they were flying, they seemed black, just like regular flies, only much more smaller. They were also very quick, I can't imagine this one I caught could actually fly quick, it's a bulky little bug. I'm not even sure this one can fly, but he is so small, I don't clearly see its back where I could notice whether he has wings.

Now, that I watched videos about different types of insects, I had to realize that I have leaf miners too in my Jack Herer, for sure.

She has the same kind of "paths" on a few of her leaves that are pictured in this video. Fortunately, the guy says I shouldn't worry much about them indoors. I pretty much believe it, since I saw this kind of path when Jack was only a few days old (that time I didn't even think it could be a pest), but since then I haven't noticed it spreading. Apart from the very first set of leaves she had, I only see this path a week or so ago on a new fanleaf, not anywhere else at all.

Well, if nutrient deficiency/lockout wasn't enough, now I have a few types of pests to figure out too. :D
I'll have an update with pictures in the evening, hopefully.


Well-Known Member
I have a plant right now with necrosis only on the largest fan leaves about like you have there. A few spots. All the other growth is perfect. I'm letting it go its course. My experience is that they will turn yellow and fall off in a week or so.
i started letting the one go too that I posted before. The flowers turned out fine even though the leaves did it look too good. Move slow and don’t make quick rash decisions.
This is the conclusion I came to in these 2 days I was away. If the spots doesn't spread, I will just let her be.


Member of the Month: Aug 2019
Good Morning,Alice,
That little bug you caught-if you can count them-a spider mite will have 8 legs,a
regular "bug" will only have 6- but if you can't see wings,you probably won't be able to see legs clearly enough to count...

The pesky little"flyers" sound like soil gnats-you'll soon have more if that's what they are...
I treat my plant's water with "mosquito dunks"-It takes about 2 weeks (or 4 waterings) to get rid of the little buggers-the larvae will die pretty quickly,then you just have to wait for the adults to die off...

The adults don't eat,they only drink,so they don't do anything but be annoying (and lay eggs in the soil)....the larva,however,can damage your roots if you end up with a true infestation.

Aphids also fly until they land on your plants-then their wings fall off and they start laying eggs.
The eggs,and the aphids are usually most prevalent on the undersides of the leaves,which you might want to check ,because aphids can become a real problem,real fast...
Maybe google "brown aphids" to compare with that little bug you caught...I hope it isn't one,they're a real pain to get rid of once they get established on the plant...


Member of the Month: Aug 2019
Mosquito Dunks are little 2" donut looking things that you drop into the water that you use to water your plants-(like in a 5 gallon bucket) they release microorganisms into the water,which are harmless to the plants,and humans,but toxic for the gnat larvae.(and,of course,Mosquito larvae)

You drop one in the bucket of water and let it sit for 24 hours so the bacteria can populate the water,then it's ready to use on your plants.

They don't dissolve-they just kind of break up in the water,so you'll see little brown chunks in the water,which you can strain out if they bother you -I just leave them-they don't hurt anything...
You'll find Mosquito Dunks at Home Depot,or Lowes,or any other place where they sell bug killing supplies-
they come on a card of 6 ,or maybe 8,and they cost about $6.00.

Each donut is good to treat the water for 30 days,so just keep refilling the bucket with the dunk in it,and after a month,drop another one in....
They work very well,but they do take 2 weeks or so to work their "magic"


Member of the Month: Aug 2019


Well-Known Member
I checked the brown aphids on google, they have longer legs just like spider mites have. This one has very, very small, short legs right under his body. I used my phone's flashlight, now I could see that its whole back is brown, while its head is dark black. I can only see the tiny legs, but can't really count them. I'm trying to find a loupe somewhere, so maybe I can get a better look of him.
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