Organic NoTill Bed is failing badly

[RJE231]

Established this bed about 60 days ago, the soil has been cooking for about 80-90 days and is the following mix;

40 Gallon mix

3C kelp (1-0-2)
2.5C crab meal (10-0-0)
2C neem/karanja
2.5C Malted Barley/Rye
1.5C AlfAlfa (3-1-2)
2C Fishbone Meal (4-13-0)

5C Gypsum
5C Oyster Shell flour
5C Basalt
5C Glacial


1/2 bale peat + coco - 13 gallon
Compost (fish/cow/sheep) - 7 gallon
EWC - 6 gallon
Aeration - 2 gallon biochar / 11 gallon perlite/lava/rice hulls

The plants are 4 autoflowers, they all started off GREAT with explosive growth right off the bat, things started to go bad about a month ago with the NEW growth tips showing some light yellow + burnt tips. This has slowly progressed with most of the top colas being surrounded with light yellow leaves with brown patches near the center of the leaves.

The peculiar thing is I've got 1 plant (see pics) that looks COMPLETELY FINE, nice dark green with 0 signs of issues and it's 6 inches away from the others. The ones that are struggling the growth about halfway down the plants looks a perfect healthy green with basically no signs of yellowing. This issue is entirely isolated to the top growth of the plants.

I've done the following to try and help,

- Fed with 1/2 strength Calmag from a bottle twice
- Fed with 1/4 strength Pro-Tek by Dynagrow
- Fed with 1 TBSP of Epson Salt per 2 gallons of water
- Fed Molasses + Cannazym once for flowering boost
- Fed with Aloe Vera
- Aerated Compost tea twice, last time was today using a recipe with EWC, kelp, Alfalfa, molasses, Humic Acid and Soft Rock phosphate.

I've checked for insects and found soil mites (8 legs, no 'pipes' on the asses), small white worm-like bugs crawling through the top of the soil that can jump (springtails?) and some fungas gnats which I've been able to deal with by using BTI + Nematodes + Sticky traps. The traps show the Gnats are very much under control and I don't often see fliers. Other than those insects + red wrigglers I've not discovered much else and I've been looking pretty diligently.

The pH of the soil (slurry test) came out to be ~6.7pH and the runoff was around ~7.05pH which seems just fine for an organic bed from what I've read. At this point I'm thinking the issue is to due with my original mix not being well balanced or a lack of Phosphorus? Boron kind of lines up but I use tap water and water frequently to keep things moist + use a cover crop and mulch.

Environment seems good, the top of the canopy is ~80F while the ambient of the tent is ~75F, humidity is ~55% and it stays constant as I run the lights 24/0. Air is always moving via a small circulation fan that blows gently across the top of the canopy just enough that the fan leaves gently move. Air is exchanged via a large carbon filter + fan combo in the ceiling of the tent that is more than enough to keep the air fresh.



The second attached picture shows the plant that's doing just fine despite sharing the same soil as all the others, it's simply a little behind as I started it about 2 weeks after the others.

 

[Weird]

I am assuming you have a big 40 gallon bed?

After looking at your mix it seems very compost and casting heavy, drainage poor. Feeding it anything is counter productive the rock phosphate could be burning it. I also would not use alfalfa in flower and even small amounts of alfalfa can burn the shit out of plants if the soil isn't cycling perfectly

 

[RJE231]

Yea, it's a 45 gallon smart pot with the bottom ~2 inches filled with large lava rock for drainage and the top ~2 inches topped with mulch + cover crop.

I thought the standard was one third drainage, one third compost, one third peat/coco - what do you suggest for a superior ratio? As for the alfalfa in the tea it was just a pinch in a 5 gallon brew so hopefully it doesn't make things too much worse. If the bed is in fact too hot how do I go about 'cooling' it down? I've been mulching like crazy and adding red wrigglers. The cover crop is starting to really boom so I'm hope it helps balance things as well?

Will a straight flush really do anything in an organic grow like this? I've never had the need to flush an organic soil grow so I'm not sure how to 'reset' other than just waiting it out?

 

[thailer]

i can only think of two things but i can't say for sure. my first impression is maybe even though the RH is 55%, at canopy level under hot lights and with a fan rustling the leaves, even ever so gently could cause the leaves to dry out and get burnt. since it's only the tops and one plant isn't effected, maybe you could look and see if the plant that looks good is getting buffered by the wind/less wind than the others?? or your lights are too close that could cause some bleaching?

 

[Limeygreen]

How do you water them? Do you allow for dry down in between or keep fairly wet? How much drain do you get? To me it seems like you are missing some minors like Iron and Manganese, some varieties of plants require much more and it always shows up in upper growth, too much P can tie them up.

Recipe seems quite strong over all imo, some burnt tips show you're pushing hard enough, why the extra cal mag etc in there?

 

[CimbaKat]

Autos soil needs to be not as nutrient rich as photosn not sure if that's going on. I'm not I n the proper headspace to read over your recipe to be honest but I'll give feedback as I've dealt with this issue.


Could be your lights... how low are they? Type, LED CMH, MH, HPS etc? What's the company recommended heights per stage. Did you transplant, use the axons use too much? Can burn planta? Are you over watering? Undrwatering? Are your plants praying to the sky? Or limp/curling in? Just chillin? If not praying, maybe your light is too intense. Your pH seems alright. What's your pH of your actual water and not run off? Is it well water? I recently had my light too low (LED) and was burning my plants for a few days until I was able to rig it right. Turns out I also had a water issue (well water, high in iron, sulphur and locked plants out from too much iron plus the light issue). Didnt realize it may be water because I knew it was the light, turns out it was both. IMO add nutes last after every I is dotted and t is crossed. Especially with autos. If your soil which it should be if you followed a super soil recipe that is reputable than its fine and it's another issue, now your soil is fucked if it's not nutrient issue and you're compounding the problem by adding things. I haven't added shit to my soil and the plants look ugly color wise but buds are pretty and stinky caked up crazy and stacking despite the burn and shit water. Just takes time and faith. Had a runt that looked like ita gonna die turn into hopefully a runt that will yield 2oz of White OG kush goodness


Patience is a virtue. Sometimes trouble shoot and ride it out. Hope any of this helps. Like I said use notes only when your so goddamned certain. Hard to flush em outta soil...

 

[troutman]

Adding lots of carbon rich material like straw and leaves will tie some nitrogen
and other excess nutrients while they decompose. This may help your plants.

 

[RJE231]

Adding lots of carbon rich material like straw and leaves will tie some nitrogen
and other excess nutrients while they decompose. This may help your plants.

Added more tonight

Could be your lights... how low are they? Type, LED CMH, MH, HPS etc? What's the company recommended heights per stage

315w CMH - I raised them tonight to above 21" to the closest plant, this may have been a factor that I overlooked.

How do you water them? Do you allow for dry down in between or keep fairly wet? How much drain do you get? To me it seems like you are missing some minors like Iron and Manganese, some varieties of plants require much more and it always shows up in upper growth, too much P can tie them up.

Recipe seems quite strong over all imo, some burnt tips show you're pushing hard enough, why the extra cal mag etc in there?

I water enough to keep the bed moist, usually 1.5-2 gallons every 1-2 days does it. I usually get a tiny bit of runoff but my main goal is to keep the top layer moist. I added the calmag from the bottle as things looked like mag when it first arose which is why I tried straight epson salts as well. If you mean the original mix then I was just following the base recipe I got elsewhere. The calmag I added has some Iron in it as well https://www.advancednutrients.com/products/sensi-cal-mag-xtra/

Is there anything I can do to help remove excess P from the soil besides the cover crop and just time?

i can only think of two things but i can't say for sure. my first impression is maybe even though the RH is 55%, at canopy level under hot lights and with a fan rustling the leaves, even ever so gently could cause the leaves to dry out and get burnt. since it's only the tops and one plant isn't effected, maybe you could look and see if the plant that looks good is getting buffered by the wind/less wind than the others?? or your lights are too close that could cause some bleaching?

I've moved the lights away as that may have been part of the problem for sure, I've also done some testing and the RH right in the canopy area is saying ~40% so I've added a humidifier to the setup to help boost that canopy humidity up hopefully. I've also moved the fan up slightly so the plants are still experiencing airflow but it's reduced.

Thanks for the input everyone, I've taken the suggestions and if nothing else the overall environment has been improved by properly distancing the light and improving the humidity in the canopy.

 

[redlaser]

Phosphorus doesn’t rinse out easy like nitrogen would for instance.
You could do a soil paste test to find out ph and EC.
Average sample, inch of sample to inch and a half of water
Can get a basic soil test for 60$, might not seem worth it, but the paste test would get you some answers.

If you find out it’s too hot you can dilute it with peat and aeration or whatnot.


I have a batch of similar soil, a few things different like no compost, forest humus instead, no coco and soft rock phosphate added in the mineral mix. I’ve had it three years and tested it a couple times and it’s like 10 times recommended iron, double phosphorous, three times needed magnesium, seven times as much sulphur needed, twice needed calcium according to Spectrom Analytic lab in Ohio.

 

[Scrappy-doo]

Light burn. Dead give away is when you mentioned that the lower canopy is unaffected. Got to be careful with those cmh lamps. Because of the spectrum they need to be kept further away than an hps of equal wattage would. I've had and only recently corrected this issue myself!

Here's a couple of excellent articles that detail your problem and provide a clear understanding of what's going on.

https://www.growweedeasy.com/cannabis-plant-problems/light-burn

https://www.growweedeasy.com/how-far-grow-lights

 

[RJE231]

Light burn. Dead give away is when you mentioned that the lower canopy is unaffected. Got to be careful with those cmh lamps. Because of the spectrum they need to be kept further away than an hps of equal wattage would. I've had and only recently corrected this issue myself!

Here's a couple of excellent articles that detail your problem and provide a clear understanding of what's going on.

https://www.growweedeasy.com/cannabis-plant-problems/light-burn

https://www.growweedeasy.com/how-far-grow-lights

I'm really hoping this solves my issue, thanks for the links!