Nutrient deficiency or burn

Hi Cannafam, I'm new to this site and have been reading articles and applying methods and not winning the war on deficiency or nute burns of which I'm not sure. I have been growing for 2years now and always have 3 of 9 plants dying in my 5x5 tents🥺

Here the breakdown:
Grow space 5x5
Ac infinity 6inch with carbon filter
2 oclialting fans
Mycelium bags
Hlg rspec2 led

Veg humidity range and temps 20-25c and 55 to 65 rh

Feeding organic amendments greenhouse seed co the bio grow 45gr and the bag says it lasts for 2months then you can top dress.

Soil 90-10 coco an perlite

In week 6-8 some plants start showing deficiency or burn and others are thriving I check soil ph weekly with bluelab soil ph pen that ranges between 6.0 an 6.5

Please help me as I'm thinking this is calcium deficiency but want to be sure before I add some calcitric lime as I only wish to use organic amendments to solve the issues...
 
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Looks like pretty advanced potassium deficiency.
Is potassium demand high in veg stage of the plant as I just checked the npk values for bio grow 7-2-4.. should I supplement with some seabird gauno or add banana peel to top of soil and water every other day as I have read about ot providing a constant supply of potassium...
 
Do you let your plants sit in the run off?
No I water with a pressure sprayer to minimize runoff and not loose the nutrients in the soil.. however if there is runoff I throw the water out of the draining pan to prevent overwatering.. could this be calcium deficiency as I water with r/o water and I do not supplement with any calcium...
 
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hard to tell by the pictures, is it mostly the top leaves with the burnt edges?
Yes it usually starts at the top having the most affected areas then works itself down. I added another pic that was 2 weeks ago the early stages of the problem
 
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What is the soil you are using? That has a lot to do with it. Also if you said you are adding coco and perlite, the coco may be at the heart of your issues if you are mixing and directly planting. Coco is alright in a soil blend if you can let it sit for a bit and really become a part of the soil, but if you mix and plant immediately I find problems tend to arise.

On to your nutrients, I am a bit confused here. Are you top dressing with the Greenhouse nutrients once and letting it go for 2 months before applying again? Are you mixing it directly into your soil blend?

How often are you watering? How much water are you giving each time? Is there runoff when you water?
 
What is the soil you are using? That has a lot to do with it. Also if you said you are adding coco and perlite, the coco may be at the heart of your issues if you are mixing and directly planting. Coco is alright in a soil blend if you can let it sit for a bit and really become a part of the soil, but if you mix and plant immediately I find problems tend to arise.

On to your nutrients, I am a bit confused here. Are you top dressing with the Greenhouse nutrients once and letting it go for 2 months before applying again? Are you mixing it directly into your soil blend?

How often are you watering? How much water are you giving each time? Is there runoff when you water?
I purchase the soil pre mixed from freedom farmers in south africa that already has coco and perlite mixed at a 90/10 ratio I then top dress with 45gr of grow after 3 weeks passed by from seed as they meee no nutes during the 1st 3weeks.

I have not applied again as greenhouse grow amendments mention that you only top dress after 2months so the plants have only been receiving water.

Almost no runoff as I water with garden sprayer like 5percent runoff max.

I water the plants every 3days depending on if the pot is light or not some plants are drinking more water than others.

I also use a blue lab pulse meter to ensure I can check soil moisture to avoid over watering.
 
Temps are running between 22-26c with an ac so I doubt its heat stress.. anything else that comes to mind as I'm not sure how to treat the problem
 
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I purchase the soil pre mixed from freedom farmers in south africa that already has coco and perlite mixed at a 90/10 ratio I then top dress with 45gr of grow after 3 weeks passed by from seed as they meee no nutes during the 1st 3weeks.

I have not applied again as greenhouse grow amendments mention that you only top dress after 2months so the plants have only been receiving water.

Almost no runoff as I water with garden sprayer like 5percent runoff max.

I water the plants every 3days depending on if the pot is light or not some plants are drinking more water than others.

I also use a blue lab pulse meter to ensure I can check soil moisture to avoid over watering.

I don't know anything about the soil mix you are using, like what are the inputs, how much organic material is going into it and how long it has been cooking before you are purchasing it. This is one advantage of bagged mixes. So for all I know the soil could be too hot for young plants and that may be causing all your issues.

So your nutrients may be a bit of an issue. To start if you are top dressing with dry amendments you need to be applying that dressing about a week before your plants actually need the food. If your plants need food at day 21 of their life top dressing will not give them the food when they need it. Typically dry soil amendments need time, around a week, before they are broken down enough and made their way far enough into the soil to provide your plants with nutrients. So you really want to be top dressing at day 14-16 so by day 21 that food is available to your plants.

I also have a very tough time believing that one application of top dressed food is enough for 2 months of growth. That would be the only top dressed nutrient that I am aware of that lasts this long. If this is true then it may simply be too hot a blend for your young plants. My real question is what is in there, clearly something that no other product on the market has included, that is giving food over such an extended period of time.

45 grams also seems way too much to be applying to a single pot. I am not sure why you are applying so much at any given time. For a top dressing just enough to be noticeable on the top of the medium is all I would apply. I do know that the Greenhouse brand of nutrients were actually meant for crops growing in the ground or large planter beds rather than in small pots; this may also account for the discrepancies in how much and how often you are applying. Double check and make sure you are applying at the recommended proportions for small pots rather than for plants in the ground. I may consider using a different brand of nutrients and see how your plants do with that, if you no longer have problems it was the nutrient that was the heart of your issue.

Ultimately it sounds like you keep doing the same things and having the same issues. It is time to start changing things up to determine where you are having problems. This is one of the times where copying what successful growers have done may be beneficial.
 
Firstly thanks for taking the time to assist a fellow grower.

The soil that im using is premixed see attached link: https://www.freedomfarms.co.za/craft-soil/

Organic Classic
Ingredients: Coco Coir, Worm Castings, Compost, Perlite (10%), Vermiculite, Volcanic Rock Dust, Bone Meal, Gypsum, Fermented probiotic bran, Organic nutrients
Application:
– Ideal for container growing
– Indoor, Greenhouse or Outdoor cultivation
– Quality organic potting soil for vegetables, herbs and general plants
– Raised bed system re-planted over multiple cycles (No-till, covercrop)
– Cultivation of organic medicinal grade CBD plants

The Organic Classic blend is formulated mainly for organic growing practices and organic nutrients. Compared to the Formula 1 mix, the Classic has a greater Cation exchange capacity (CEC), higher active organic matter content, as well as a balanced semi-slow release organic nutrient component. It will also hold water longer than the Formula1 mix. Substrate pH 6.5.
First watering can either be clean water or for hungrier plants add a single recommended dosage of organic nutrients. The nutrients in the soil should be adequate for approximately 2-6 weeks before additional nutrient applications are required.

The temps in my soil currently is 22.5c which isn't hot i presume...

The nutrients description see attached link: https://shop.greenhousefeeding.com/bio-grow-en.html

BioGrow

How to use:
BioGrow needs to be mixed into the substrate. It can be used in soil,
coco or similar substrates.

It can be mixed at the time of transplantation or added later as top
dressing (mixed into the top layer of the soil)

The nutrients will be released constantly during a period of 8
weeks.*


*If the growth period is less than 8 weeks or the substrate is
pre-fertilized, doses should be decreased. Use half dosage for seedlings
and young plants (2-3 weeks old). If the growth period is longer,
a second application is required (as top dressing).

Dosage:
Vegetative growth:
3g per Liter substrate

Mother plants:
2-3g per Liter substrate every two months (as top dressing)

My pots are 15ltr pots which equals to 3gr X 15=45gr top dressing every 8weeks... Is this product not giving me proper information on their feeding regime or am i being ripped off as its very expensive.

I am not an experienced grower as this is my 2nd year in growing and wish to grow organically and thought top dressing is the easiest way for a beginner in organics.

I hope this give you enough background to diagnose my problem..
 
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Ok, so the soil does seem very rich, and may actually require being run a little on the dry side. I find that nutrient rich soils should be run on the drier side to really get the most out of them, seems weird but that is what I have seen in friends grows and the occasions when I use nutrient rich soils.

On top of that you are adding a full dose of the nutrients, which just imparts more minerals and nutrients and you have hit a point of over-saturation with nutrients. Right in the instructions of the nutrients it says to use a lowered dose if you are using a nutrient rich soil, which you are. The directions also say the amount you applied should be mixed directly into the soil; this is surprisingly important. When the dry fertilizer is blended into the soil it is spread out throughout the entirety of the medium so the roots come in contact with the nutrients as they spread out through the soil. When you put that amount on as a top dressing it forces the whole dose at the roots, particularly the top layer of roots, which is too much at a single time. At that I would always recommend using half of the recommended dose on any bottle or bag of nutrients anyway. Ultimately you keep overdosing your plants with nutrients. Back off on how much food you are giving your plants.

At this point I would personally repot your plants into some fresh soil without applying the fertilizer. After 3 weeks or so you can sprinkle a little over the top of the soil, not 45 grams, so it will continue to feed them for another 2 weeks. So if your veg period is 8 weeks, your first three weeks are just water, then you apply the first top dressing. At week 5 then again at week 7 you would apply your top dressings. You may use 2 grams or so of nutrient per dressing, way less than you are using now.
 
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QUOTE="canorganix, post: 2394080, member: 114220"]
Hi Cannafam, I'm new to this site and have been reading articles and applying methods and not winning the war on deficiency or nute burns of which I'm not sure. I have been growing for 2years now and always have 3 of 9 plants dying in my 5x5 tents🥺

Here the breakdown:
Grow space 5x5
Ac infinity 6inch with carbon filter
2 oclialting fans
Mycelium bags
Hlg rspec2 led

Veg humidity range and temps 20-25c and 55 to 65 rh

Feeding organic amendments greenhouse seed co the bio grow 45gr and the bag says it lasts for 2months then you can top dress.

Soil 90-10 coco an perlite

In week 6-8 some plants start showing deficiency or burn and others are thriving I check soil ph weekly with bluelab soil ph pen that ranges between 6.0 an 6.5

Please help me as I'm thinking this is calcium deficiency but want to be sure before I add some calcitric lime as I only wish to use organic amendments to solve the issues...
[/QUOTE]


Imho to much nitrogen. Way to much. Food im veg. have more n. in, becase flowers need't for grow.Remember less is more.
Feeding schedule?
 
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the leaf curling and brown edges looks like heat stress. some strains are more sensitive than others and/or run "hot". I have a girl now with leaf temps only 1 degree below ambient. others i have are 4 degrees below. try dimming your light a bit see if that helps them relax.

regarding organic wishes, try building a more complete soil to try to mitigate feeding issues later in the grow.
 
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Is potassium demand high in veg stage of the plant as I just checked the npk values for bio grow 7-2-4.. should I supplement with some seabird gauno or add banana peel to top of soil and water every other day as I have read about ot providing a constant supply of potassium...
K is always in demand. Start to finish.
 
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