Deficiency, Burn, or Something else?

Grow Cycle
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Strain; Kush Auto from Seedsman

Soil in pots, Hydroponic, or Coco? Coco, 7 gallon fabric pots

System type? Hand Water

PH of runoff or solution in reservoir? 5.8

What is strength of nutrient mix? EC, or TDS 665 ppm nutes +calmag before about 100 ppm of additives (hard water currently at about 150)

Indoor or Outdoor Indoor

Light system, size? 1200w Meihz LEDi x2

Temps; Day, Night Day = 26ish, Night = 23ish

Humidity; Day, Night 50-55 day, 60 night

Ventilation system; Yes, No, Size yes, 8 inch

AC, Humidifier, De-humidifier, all of the above

Co2; Yes, No no

Ok, the biggest and furthest flowering of my first crop is the Auto Kush. Still stretching up despite the problems I see. Yellow tips. Tent is all autos running 20/4.

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I am using GH hardwater nutes, and currently still feeding in late veg feed as some advice I read suggested that in autos, to do so until the stretch stopped, then switch to flowering.

I decided to increase my feeding to every other day (was letting it dry prior, but during the stretch i wanted to take advantage of cocos hydroponic properties). The increase to the overall canopy was great, the stretch is good all around, all plants look healthy except for some showing a tiny yellowing at the leaf tips. The kush in the photos, is by far the furthest along (in both flower and yellowing tips).

At first I was confused since I didn’t increase the PPMs, but I slightly dried out my RH by about 5-10% with a dehumidifier to compensate for the increased humidity from the increased feeding. So what I initially came up with is that I burned them by lowering the humidity, forcing them to transpire more, which had them drink more and get burnt by the same amount of nutes because of it, which is why it appears minor.

Now I am concerned that it might be a def because I am still using grow, or worse, a lockout.

I use drip clean every time i feed. i also feed to at least 20%, often 30% runoff, and most suggest never flushing coco with just ph water, including Canna (whose buffered coco i am using)

To add to all this, this is the only plant with red stems. Prior, since it was the only one of my plants to exhibit this and had otherwise looked completely healthy, and a google search showed that Kush was a strain that did have genetic potential for this redness, I didn’t pay much attention to it. This yellowing may be related, although it is likely not. Still, here is a pic with a few of the red branches, even going up to the leaf, is visible (blur is wind hitting leaves)

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I decided not to feed this morning to see what happened and in case I caused it to back off a bit. Not sure whether to feed tomorrow or perhaps return to more of a wet/dry cycle. As much work as hand watering every other day was, the plants definitely responded well, overall. Now I am not so sure. It might or might not have gotten worse today. Whatever it is, the progression thus far has been slow, thank goodness.

As mentioned, the 2 events immediately preceding this change (besides Kush starting to flower) were increased feeding of the same PPM to 20-30% runoff (closer to 30) and the dehumidifier being added at the other end of the tent.

If anyone has any ideas or has seen this before, let me know. It is very minor so far, which is nice, but the symptoms appear potentially a few things. I need a second (or third or 4th) set of eyes and brains, and a heck of a lot more experience than I have. I would like to address this before it gets out of hand. Thanks in advance.

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Looks like nute burn to me. And it’s not bad, Maybe dial back your mix just a touch.

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@garrigan62 @Hogmaster @Donaldj

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your humidity doesn’t seem to bad and your temps are about perfect
your plants are starting to flower you should be reducing N and increasing PK

purple stems and tip burn

Both of these key nutrients are in highest demand for your plant during flower and if ppm is too low they aren’t getting enough I would expect closer to a 1000-1100ppm at start of flower in coco if not higher

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The only reason I wasn’t already on board with the red stem potentially being potassium def is

  1. It has had red stems since sprout
  2. A search online suggests Kush carries red stem trait
  3. It is the tallest of 10 plants by a good couple inches outgrowing everyone else during the stretch from about equal canopy

The tip damage started immediately after I started a full feeding every other day with 30%+ runoff, which is why burn seems more likely than deficiency to me, but I wanted various opinions supporting or opposing my n00b diagnoses (7 gallon pots of coco takes a lot of water)

As to the low PPMs, it is an autoflower so I am using everything half strength except calmag, which is full strength (we had a little issue) and drip clean, because i dont want salts and it wont burn.

I am using mostly GH flora trio. I am following advice from a posting that is easily sourced titled “Life cycle of Autoflowering Cannabis” where the author suggests delaying flowering feed until after the stretch. I was considering going to transition nutes during this next week sometime, probably after 1 more grow feed. So far, aside from the yellow tips, it seems like it was sound advice.

Considering all of that, what PPM would you thing would be better? Does your experience with Autos suggest that the advice about flowering nutes post stretch seem correct?

It is hard to assimilate advice from dozens of different people with turkey leg buds to show, but I am trying to back decisions with science and other peoples experiences/mistakes.

(the temp/humidity is generally kept in optimal VPD range, for instance)

Thanks for your help and to the others who chimed in. I appreciate it

Here is a current pic of the canopy. The Kush is dead center, foreground with the baby flower sticking up all perky

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Plants are all 37 days old (well, I dropped the beans in the water on July 1st)

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Lol I am growing purple Kush and yes purple is a trait but your other conditions and tip burn and curling point more towards a PK imbalance than nutrient burn coco is hydro meaning if you don’t add it during your feeds it isn’t there quite simple. I grow mainly in hydro and help more than a few people through hydro grows and am typically the person who gets directed to these kind of questions based on experience and results helping people in Coco and hydro. I am not disputing the fact your plants still need N just that they are not getting enough P and K based on the low ppm

your plants look quite healthy and if you feel your current approach is doing everything you want with your ladies feel free to stick to it I am only offering a suggestion that raising ppm may give you some improvement :wink:
Good Luck

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i appreciate the advice and am certainly receptive. i did not mean to doubt your experience at all. in fact, i noticed that you were tagged, so your response was already given sufficient prestige in my mind. my apologies if i came off another way

I am doing 2.5 ml gal of micro and grow and 1.25 ml gal bloom. How might I adjust it, other than keeping the ratio at higher ppm?

should I stay at this ratio higher ppm until stretch is over or switch to my next planned move, transition at 2ml gal across the board?

or 4ml?

I have seen pics of bad burn and deficiency so I don’t want to jump to conclusions, but certainly want to correct it. I just lack the experience to adjust things correctly

i was under the impression cannabis was sensitive to nutes as it was, and autos even more so. my response was half dose and worried about that being too much

and actually i was considering doubling the dosage last week but decided to just increase feeding schedule per hydro qualities of coco

so i am not opposed to it being a deficiency, that would be easier to fix and might end up increasing yield taboot, and i can see the gains of the frequent watering again

if these were photos, i think i could figure it out myself. autos in coco in huge pots, i feel i might have to be careful to avoid losing significant yield.

thanks again, i appreciate your time

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It is simply the ppm level your ratio is fine though I would aim for 900-1000 I am currently running a aeroponics unit 3 weeks in from non rooted cuttings and they are now showing healthy new growth my ppm was at 600 prior to todays change now at 750 they were showing very similar symptoms. Until a week ago when I raised ppm all new growth since has been healthy don’t get me wrong first time in Aeroponics unit so I started with a low ppm to get cuttings to root in hind sight would start with 5-600 ppm next time :wink: My flower unit is at around DWC is at around 1500 ppm week 2 of flower. It can be confusing tip burn is typically a excess but depending on stage in plants life demands change and it can be caused by a def flower and transition is when plants are at their hungriest with increased growth and development consider this your plants can up to triple their size during transition so it’s feeding demands can easily be twice as much since the plant is becoming larger it easily like people can have a larger appetite

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ok, i am prepping the water for a feeding tomorrow approx 50% higher, same ratio

thank you for the advice, it seems sound

that being said, my runoff consistently tests 0.1-0.3 EC higher than what i put in. is this the case of the wrong nutes or simply too few/too many nutes?

Some people suggest a surplus or deficit ppm in runoff is the actual guide RE:burn vs def

or is it just a flush ppm that i can expect with runoff?

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I believe you mentioned a buffer added in the coco? but yes ppm that comes out will vary some to what is put in this is the result of build ups but if the variable is .1 .3 it is simply a matter of 50-150ppm I class a build up as a ppm raise in to out higher than 50% depending how much your ladies drink a cycle of feed feed water will typically keep you close to the variable you describe. In some systems drain to waste you feed 5 days flush 1 and repeat if you are using your coco like soil hand water and in pots you would be on a less strict schedule :wink:

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Canna says they buffer the coco

CANNA COCO medium is a pure product with a homogeneous structure and has had a full buffering to prevent that the medium consumes the nutrients, Instead the nutrients are directly available to the plant

I actually doubled the GH base nutes and only managed to get to 1.6 EC. With all additives, it got up to 1.79 EC . I am nervous I am going to burn them, but not nervous enough to not give it a shot. They are much bigger than I expected at this stage so they probably do need more nutrition to support them now

But if it does burn them, how will I be able to tell the difference on new growth between the past def and a new burn?

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If your ladies seem to perk up and being that they are quite healthy already speed up growth you know you have them pretty much dialled in slight tip burn like you have on some older growth would increase if ppm is too high to unaffected leafs. Being that you are in transition to flower stretch and speedy growth is normal during regular veg period you know it’s right because your ladies can put on inches a day in flower you know you have it right because leafs stay broad and green without hooking or burning a very slight tip yellow would mean it is right on edge which is pretty much saying you are giving it everything it can take.
This is where I love hydro since the goal is to give it everything it can take to get those monster buds and fast growth during it’s short life cycle this is why hydro is effective you can float that edge of perfect and easily adjust with a simple addition of some fresh water :wink: When I used to hit the gym I ate for the weight I wanted to be not the weight I was

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man, i think you were spot on. I overestimated how wet they would still be. They drank a lot.

Run off was low low, often LESS THAN i was putting in, the ones that were over, were only over by like 25-50 ppm. good call i think. I am much less nervous about the up in nutrients and realize they are going to be feeding every other day, its just a fact.

I will update if i swung too wildly and burn them, but I bet they are going to perk up real good now.

Thanks!

(btw, I only feed 5 at a time, hence every other day. I only have a 10 gallon container to mix in and let the tap water air out)

@DieHigh55

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hey @Donaldj

I am not sure she is getting better as far as yellow tips and red stems. She is growing like crazy. Breeder said 60cm max indoors and she is likely to hit 90cm by lights out tonight, the tallest by far. I am not sure if I should up the EC past 2 or is it possibly some other issue?

And if she is growing still, is it even an issue? Is there even an issue? Am I worrying too much?

What do you think, pic from right now?

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I suspect slightly too much N in your mix or your ph is out some? when is last time you recalibrated your ph meter? it is very common for meters to lose accuracy over time I check mine every week or 2

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hasnt been quite 2 weeks. I have calibrated since before i initially asked here. I will calibrate tonight when I am making tomorrow’s feed. I was going to up the GH additives to full strength for her tomorrow as well (floralicious + florablend).

Here is my current nute & additive regimen

full strength GH base nutes, EC 1.6, PH with white vinegar to 5.7
FloraMicro 5 ML gal
FloraGro 5 ML gal
FloraBloom 2.5 ML gal
CalMagic 2.5 ML Gal
Armor SI 1 ML gal
Roots Excelerator 0.5 ML Gal
Drip Clean .5 ML Gal
Photosynthesis Plus 3 ML gal
SM-90 2.5 ML gal
Ful-Potential 2.5 ML gal
FloraBlend 2.5 ML gal
Floralicious 1ML gal

1.79 EC after nutes and additives

it keeps stretching into the light. could it be light burn? I am moving the light up a couple times a day trying to keep it 18 inches away. it is now past 90cm. she was like 14 inches tall when she started to transition

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That’s kinda a neat way to adjust ph I use vinegar to kill weeds and as far as your nutrient mix your base ratio’s are way out your plant is starving for PK ratio should be more like 2.5ml Grow better yet strait Lucas formula 8ml bloom 4ml Micro no grow
Let me explain GH was designed to grow veggies plain and simple all the feed schedules they have are for veggies not MJ. Most experienced growers learn to tweak and adjust the formula to work for them by changing doses.
For instance after 2 weeks in flower your Base Nutrients should be more like 1 2 3 ratio Grow Micro Bloom during early veg 2 2 1 late veg 3 2 2 what this means is 2.5ml Grow 5ml Micro 7.5ml Bloom etc. adjusting dose to meet your plants need but still similar Ratio :wink:
Lucas formula uses simply higher doses of Micro and Bloom which provide extra N without using Grow and still has high enough ppm with added bonus of higher PK some say it removes the need for Cal because Micro is higher dose This is because Lucas during flower is simple 6-8ml micro 12-16ml bloom

Your current feeds are 2 2 1 GMB early Veg feed :stuck_out_tongue:

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I love GH nutrients use them myself we just have to learn more about the plants we are growing’s life cycle and needs

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so should i skip transition and go right to flower nutes? will that adjustment be abrupt or ok?

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woah. full strength cal mag with hard water. ph in 5.7-5.8. ph out 6.3-6.4

tonight i see this

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textbook, right?

do i use 150% strength of cal mag?

Do I also use 150% of other nutes?

snits getting real!

this is not the kush. the kush does not have the same effect even tho they are feeding the same

lets call this one “2 of 3”