Help i'm not sure what this is

[chris692]

Hi, First time grower in Coco. I'm using Canna coco Pro in 30 Litre fabric post. I'm using Canna coco, Rhizotonic and Coco Cal. I have a 1.2 by 1.2 by 8 foot Gorilla tent with a Adjust awing Avenger shade with 2x Philips CMH bubs. Running a 18 veg cycle during the night with temps from 23-26C. I have been Googling deficiency and can't work out what the problem is with these plants. The shoots look distorted and just not right. I have tried feeding them lowish EC around 800 right up to 1.300 EC but nothing seems to work I did a major flush 2x weeks ago with plain water which I found out later I shouldn't have so the coco has been consuming a lot of the nutrients I have been feeding them. I fed one plant yesterday (see photo IMAG0730) at 1.300 EC thinking it's a deficiency expecting it to perk up but looks worse. The runoff currently is lower EC than I put in. so 1.300 EC in and 800 EC runoff. I PH from 5.8 to 6.1 but even changing the PH doesn't make any difference. I am completely baffled and as I'm due to put them in to flowering soon I need help to work out this problem. I feed the 2x larger plants every other day and the smaller ones every three days. I know I'm supposed to feed either every day or every other day but when the pots are still heavy I normally leave it until the pots feel a bit lighter. I never let them dry out much. Any help would be good it's been an on going problem and I just want to fix it.

 

[CannaCountry]

Things to consider...

30L pot is way too big. It only makes managing things like humidity / watering all that more difficult. Don't change it now, but for the future, you can easily grow a 5' plant in a 2 gallon pot of coco, all day long.

You're going to want to do something for Mg. Your plants are beginning to look short on it and from the information you provided, it doesn't appear you're supplying it...if you're in coco, you're going to need to supply Mg through out, as well as Ca

You need to be feeding every day...at least once a day. Anything less and you will not be taking advantage of your medium's abilities and your plant's potential. This isn't a soil grow, so don't treat it as such. It's not necessary to check how heavy the pots are...feed every day regardless.

pH makes a huge difference when growing in coco. Be sure you're feeding at the right pH and if there's any question as to your past practices, take a moment to test your medium's pH to be sure it hasn't been driven out of whack.

You're not that far off on the plant, even though it looks a little unhappy. I'd just tweak things a bit and see how the plant responds...be patient. Good luck.

 

[jonnynobody]

Things to consider...

30L pot is way too big. It only makes managing things like humidity / watering all that more difficult. Don't change it now, but for the future, you can easily grow a 5' plant in a 2 gallon pot of coco, all day long.

You're going to want to do something for Mg. Your plants are beginning to look short on it and from the information you provided, it doesn't appear you're supplying it...if you're in coco, you're going to need to supply Mg through out, as well as Ca

You need to be feeding every day...at least once a day. Anything less and you will not be taking advantage of your medium's abilities and your plant's potential. This isn't a soil grow, so don't treat it as such. It's not necessary to check how heavy the pots are...feed every day regardless.

pH makes a huge difference when growing in coco. Be sure you're feeding at the right pH and if there's any question as to your past practices, take a moment to test your medium's pH to be sure it hasn't been driven out of whack.

You're not that far off on the plant, even though it looks a little unhappy. I'd just tweak things a bit and see how the plant responds...be patient. Good luck.

I'll second CannaCountry on the calcium and magnesium supplementation when growing in coco. It's a must. Kind of looks like heat stress / wind burn. Nothing resembling fertilizer burn. Do you have a fan on them? How's the heat at the canopy? If you hold your hand at the canopy level for 30 seconds does the heat / light feel intense?

If all of those things are in check you may just need to give her a kick of a good calcium / magnesium combo product and continue to routinely feed throughout the grow cycle. I personally hate coco and had a terrible experience with it in my drain to waste hempy buckets. The problem with coco is that it's not an inert medium, but it's commonly used as a hydroponic medium. Read up on cation exchange for further info. Coco is simply not an inert medium. It interacts with your fertilizer. That's not inert. Clay pebbles are inert. Perlite is inert. Hell rockwool is inert. Not coco.

I have since moved to 100% #4 chunky perlite hempy buckets and have had no issues since. It seems like people are using coco and then attempting to treat it like soil by feeding microbes and organic amendments and then they're watering it everyday like it's hydro. When I did run coco I watered every 2-3 days up until halfway through flower which was then every other day. If you water every day you will water log the medium, and your roots will suffer. I don't even water perlite hempy buckets everyday, and there is almost zero water retention in perlite. If the top of your coco is still moist you do not water. Much like soil you do not allow it to dry out, but you don't keep it constantly wet either.

I'd recommend you ditch coco after this run and move to perlite buckets. Way easier. No weird cation exchange issues with coco and calcium, and unlike coco it is 100% inert and will not in any way interact with your fertilizer regimen. In short - fuck coco happy growing

 

[chris692]

Hi CannaCountry thanks for replying I will use smaller pots next time. When they were in the smaller 5 Litre pots I was watering everyday but they didn't look well that's why I switched to waiting for the pots to dry out 50% like Canna recommended, but I do know many feed everyday and that's what I'm aiming for. I use Coco Cal which is a CalMag products I had increased the dose to the max as per their instructions which is 8ml per 10 litres. I bought another PH pen because I thought the one I have was out but it wasn't so I ruled that out. I started to test my runoff PH and PH in is 6 and out is 6.4 so within range. Hi Jonnynobody, thanks for replying after spending a lot of time researching nutrient deficiency and not finding a single photo that resembled the problem I think it might be heat although the temps are fine. I did do the hand test at around 12 inches and it seemed ok but I have been gradually moving the light further away currently it's now at 21 inches above the tallest plan and 24 from the smaller ones. I'm planing on buying a lux meter to test, with 2x 315 bulbs its so bright I need my sun glasses on My mate grows in coco so I thought I would give it a go I have only ever grown in expanded clay balls and had no problems. It is weird that the coco also needs to be fed because of the cation exchange so I'm thinking the same as you that this isn't the best medium to be growing in because it's not inert but so many people like coco as a growing medium, either way I'm stuck with it now. I was watering everyday like they say but they didn't look healthy they do look healthier if left to dry out a little bit but many people feed everyday with no problems. What EC do you normally use for plants in late veg and flowering I'm interested because the Canna chart EC in flowering are so high I can't see how it wouldn't burn the plants. Thanks you both for replying

 

[jonnynobody]

I use tap water with a starting ppm of 129. I add fertilizer to 800-850 ppm. 1.8 EC if I remember right. Total feed is 670-720. In the past I have run as high as 1000 ppm, but the plants experienced a bit of burn. My sweet spot is right between 800-850 total ppm. No burned leaves and lush growth. Fertilizer doesn't grow flowers. Light's do. Fertilizer just allows the plant to complete it's metabolic processes. Plants make their own food. The only way to get bigger flowers is to get a bigger light.

 

[chris692]

I also use tap water my EC is 200. 800-850 ppm that's a lot more than I'm feeding mine I will have to up my nutrients slowly. To get to that PPM I would need an EC of around 1.400 to 1.500 of the Cocco A & B then a full dose of CALMAG would bring it up to 1.800. This adding CALMAG robs the plants of nutrient solution because it consumes the EC. The 2x CMH bulbs in the large Adjust awing is so bright I'm sure my plants will love it once they start to head. Thanks for getting back so fast, appreciated.

 

[jonnynobody]

I also use tap water my EC is 200. 800-850 ppm that's a lot more than I'm feeding mine I will have to up my nutrients slowly. To get to that PPM I would need an EC of around 1.400 to 1.500 of the Cocco A & B then a full dose of CALMAG would bring it up to 1.800. This adding CALMAG robs the plants of nutrient solution because it consumes the EC. The 2x CMH bulbs in the large Adjust awing is so bright I'm sure my plants will love it once they start to head. Thanks for getting back so fast, appreciated.

"This adding CALMAG robs theplant of nutrient solution"

Calcium and magnesium are nutrients. Not only are they nutrients, they're considered macro nutrients to the cannabis plant. They are both just as important as N, P, & K.

I just had to correct a nasty calcium deficiency in my flower room, because I began running a new strain. She has different needs than the strain I had been accustomed to growing for over a year, and boy did she let me know about it. My base fertilizer, maxi bloom, typically has enough of everything the plants need. Hash plant is unique though. She requires heavy amounts of calcium and magnesium. I did not know this, and learned the hard way.

I walked into my flower room last week to discover brown ugly rust spots developing on the leaves of one of my largest hash plant ladies. The problem began spreading to another plant. Within 3 days 3 plants had the issue. I also observed a smell in the flower room the resembled decay. That's never a good thing, and something I had never experienced before. When it happens in a tomato garden it's called "blossom end rot." My ladies were getting blossom end rot. Look up pictures. It's not pretty. Cannabis shows blossom end rot in an equally destructive way.

I dosed my reservoir at the recommended rate of 1 tsp/gallon. This was too high. Botanicaire's cal-mag is very concentrated. I would recommend halving the rate to 1/2 tsp/gallon. I had to dilute my reservoir, because the PPM shot from 800 with my base fertilizer to 1200 ppm with the cal mag. I diluted back down to 840 ppm.

In a nutshell my plants have all since recovered and have a new luster in their leaves. The rot smell is gone as well. I am now incorporating cal mag into my feed regimen for all strains at a 2.5ml per gallon to prevent this issue from happening again.

The lesson to be learned here is that calcium and magnesium are crucial elements to the cannabis plant's life cycle and growth, particularly in flower. All cannabis fertilizers should have a label that reads N-P-K-Ca-Mg, because to cannabis calcium and magnesium are macro elements. They use a lot of both, and are not micro nutrients.

Always halve the recommended rates from the fertilizer manufacturers. They always recommend too strong of a dose.

 

[jonnynobody]

I also use tap water my EC is 200. 800-850 ppm that's a lot more than I'm feeding mine I will have to up my nutrients slowly. To get to that PPM I would need an EC of around 1.400 to 1.500 of the Cocco A & B then a full dose of CALMAG would bring it up to 1.800. This adding CALMAG robs the plants of nutrient solution because it consumes the EC. The 2x CMH bulbs in the large Adjust awing is so bright I'm sure my plants will love it once they start to head. Thanks for getting back so fast, appreciated.

Do what's best for your ladies. I run 500-600 total PPM in my clone buckets.