1st Grow: Please Help with Canna Coco + Plants turning Yellow

Hello All,

First off, thanks to all the people that actively post! It is because of their knowledge, I have been able to make it this far :)

Now on to business...

It has been about 3 weeks old since the seeds popped through the Coco. I have noticed over the past week or so that the leaves are starting to turn yellow. They are still growing but I can tell something is wrong.

I am guessing it is a Nitrogen deficiency, but I am so new at this, I wanted to ask the pros!

To be on the safe side, I flushed them this morning with distilled water (6.0ph) and majority of my run off was coming out at 5ph and has a yellow color when collected in a cup.

If someone could take a look I would be grateful! :)

Let me know if you need any more information.

Pic below..

Your Equipment:
.1) Type and wattage of lights.
600w HPS

.2) Distance from tops?
25-30"

.3) Reflector type? (cool tube set-up, bat wing, enclosed reflector, bare bulb...)
6" Air cooled hood

.4) Is there a consistent fresh air supply?
Yes I have a 435cfm pulling constant fresh air

.5) Do you have an exhaust fan and a circulation fan?
Yes

.6) What are the bulb wattages, kelvin ratings, and schedule?
600w, not sure, 24hours

Your medium:
.7) Specific brand and type of soil?
Canna Coco with a small amount of perlite (from beer cup transplants)

.8) Size of container.
1 gal

.9) Did you use peat pucks (or similar) to root clones or germinate seedlings?
I germinated seedlings into beercups with 75% Canna Coco 25% perlite as to not drown them.

Your nutrients and water:
10) Source of water? (tap, bottled or filtered) What's it's ph before adjusting?
Currently using Distilled water at 0ppm.

11) Method of checking water ph. (ph pen, test strips, aquarium test kit...)
ph pen

12) Method of adjusting water ph. (phosphoric acid, white vinegar, hydrated lime, PH Up...)
ph up, ph down powder

13) Specific brand and N-P-K ratio for each bottle. List dosages (quantity per gallon) and current feeding schedule.
Canna Coco A + B
10 ml per gallon (each)
5 ml CalMag
5 ml Canazyme
5 ml Rhizo
I water every 24 hours

14) How often are you watering between feedings, and how much per watering?
Water every 24 hours, I aim for 10% run off.
Most of the girls are drinking 400-500ml a day

15) Any additives or tea's? (Superthrive, CalMag, molasses, Mother's Earth...)
5 ml Calmag

16) Are your ph levels stable, or do they fluctuate?
5.8-6.0
they do not fluctuate

17) What is your ingoing water's ph? ...your runoff ph?
My runoff is around 5.0ph

18) Do you foliar feed? If so, with what, how often, and at what time do you spray?
No

Your growroom:
19) Indoors or outdoors?
Indoors

20) What size of closet, room or hut?
4'x4'x7' Grow Lab Grow Tent

21) What are the temps and humidity levels while lights are on? ...With lights off?
Temps range between 70-75F
Humidity is very low, under 20%
Lights are on 24/7

22) Have you seen signs of insects in the growroom?
No, not at all

Your strain:
23) What strain are you growing? (Indica dominate or Sativa dom?)
All are mixes
L.A. Woman
Cheese
Lemon Skunk
Arjan's Haze #1
White Rhino

24) From seeds or clones?
Seed
25) Is this an autoflower strain?
No

read the plant problems page and see what they need sounds and looks like a major decencies to me... have you fed them at all??

Quote:

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Originally Posted by mainegrown

read the plant problems page and see what they need sounds and looks like a major decencies to me... have you fed them at all??

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I have looked at the plant problems page, which is where my Nitrogen deficiency guess came from.

I have been feeding them this regimen for the past week or so:

Canna Coco A + B
10 ml per gallon (each)
5 ml CalMag
5 ml Canazyme
5 ml Rhizo

I water every 24 hours.

Prior to that I was at half strength for a week and a half.

Maybe someone familiar with the Canna line will jump in. My very limited understanding is the A+B is supposed to be complete, and designed for coco. So I'm not sure what the Rhizo / Cannazyme might be doing for you at this point. My uneducated guess is that it's not needed.

Calmag is generally recommended if you're using distilled water, esp. in coco. But again, A+B may cover that requirement for you. You might wanna research that, sorry, IDK. Seems like a lotta stuff for younguns, especially sativa-types which can be very light feeders.

I normally alternate feed / water in coco. If feeding every time, I do a little more runoff (~25%) and tune the nutes a little lighter to prevent buildup in the medium. I would definitely check the ppm of your runoff, and compare it to what's going in. Might be too hot. How were the plants doing at half-strength nutes?

I have seen lots of folks have problems trying to veg under HPS. OTOH, lotsa peeps here get good results with it, but 24/7 @ 600W seems like a lotta power for seedlings. I'd be doing this under a couple 6500K shoplights and save some $, if nothing else. I really like bluer lights for veg. YMMV.

I'm gonna suggest your pH may be a problem. If you're putting in nute solution at 5.8-6.0 and it's coming out at 5.0, the pH of your coco medium's gotta be lower than 5.0 to knock it down that far. :eek: If your pH in the pot is <5.0, you're risking "lockout," which simply means your plants can't use whatever nutes may be there (nitrogen included).

A thorough flush (3X pot volume) followed immediately with a light feeding should help. At least, in coco, it's not gonna hurt...:) pH below 5.2 in coco has been ugly for me...

Quote:

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Originally Posted by DreadedHermie

Maybe someone familiar with the Canna line will jump in. My very limited understanding is the A+B is supposed to be complete, and designed for coco. So I'm not sure what the Rhizo / Cannazyme might be doing for you at this point. My uneducated guess is that it's not needed.

Calmag is generally recommended if you're using distilled water, esp. in coco. But again, A+B may cover that requirement for you. You might wanna research that, sorry, IDK. Seems like a lotta stuff for younguns, especially sativa-types which can be very light feeders.

I normally alternate feed / water in coco. If feeding every time, I do a little more runoff (~25%) and tune the nutes a little lighter to prevent buildup in the medium. I would definitely check the ppm of your runoff, and compare it to what's going in. Might be too hot. How were the plants doing at half-strength nutes?

I have seen lots of folks have problems trying to veg under HPS. OTOH, lotsa peeps here get good results with it, but 24/7 @ 600W seems like a lotta power for seedlings. I'd be doing this under a couple 6500K shoplights and save some $, if nothing else. I really like bluer lights for veg. YMMV.

I'm gonna suggest your pH may be a problem. If you're putting in nute solution at 5.8-6.0 and it's coming out at 5.0, the pH of your coco medium's gotta be lower than 5.0 to knock it down that far. :eek: If your pH in the pot is <5.0, you're risking "lockout," which simply means your plants can't use whatever nutes may be there (nitrogen included).

A thorough flush (3X pot volume) followed immediately with a light feeding should help. At least, in coco, it's not gonna hurt...:) pH below 5.2 in coco has been ugly for me...

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Thank you very much for helping out!

I am totally with you on the ph causing nute lock-out, so I flushed them yesterday with straight distilled water. I am going to get a RO unit this week so flushing will be much easier. I don't know if it is my eyes, but the new growth seems greener today!

After some further research, you are certainly right! It looks like I should have been alternating between feeding water and plain water to rinse the salts out.

I did raise the light as well, as to not "blind" the girls.

I will measure the runoff of my ppm later today and report back.

Other than that, is the low humidity an issue?

Thanks again :thumbsup:

When I was feeding at half strength the plants seemed better, but it did not have the dark uniform green color I see all over the boards.

At that point I thought I was feeding too light and doubled, but things have obv not improved.

i have not found a low humidity to be an issue... i run under 20% relative almost all the time and no one has said boo about it so not an issue,

good luck and hope you follow directions better in the future.. the bottle knows whats up (at least it better!)
peace
-J

Quote:

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When I was feeding at half strength the plants seemed better, but it did not have the dark uniform green color I see all over the boards.

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That foliage color is strain-dependent. Last year I had spruce-green indicas (almost blue) alongside a yellowish-green sativa--so yellow I named the mom "Goldie." That's just how she grew. She liked her nutes half as strong as the indicas, and liked an 11-hour day for flower, too.

Here's something I already posted about pH:

Quote:

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There's a table floating around on this board somewhere that shows which nutes are absorbed at what pH. (It's different.)

You WANT some drift. High 6's is a bit out of the sweet spot but in my experience, no big deal unless you leave it there.

I had some pH swings in a coco test I did until I added the plants into the experiment. Then everything leveled out.

But if you can knock the pH down to a number you like, and it slowly and predictably swings back up through all the nutrient uptake ranges, that's just about ideal, IMO.

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I was responding to a poster who was having wide pH swings using RO water. Distilled water's even trickier. Be aware when flushing with it (I sometimes Cal-mag it, even for a flush) because with NO dissolved solids it tends to suck everything out of your medium. Kinda "un-reverse osmosis." :D

Quote:

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RO water with only CalMag in it has very little "ionic strength" to it. In other words, one drop of pH-up or pH-down will have a profound effect on your readings. There's no chemical buffer there to slow down the swings. Doesn't take much to tip the balance.

Get yourself some nice hard tapwater and A/B it against how your RO is acting with your pH adjustments. Dissolved minerals make the tapwater seem more "stable."

Or, try pH balancing distilled water. (The less dissolved solids you have, the more wildly your solution will react.) HTH, Hermie

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I would advise AGAINST following "bottle directions" for nute strength until you confirm the manufacturer's feeding dosages are intended for cannabis. Many are not, for a variety of legal and regulatory reasons--even brands that are obviously aimed at the cannabis market. Weed "thrives on neglect" and is generally a comparatively light feeder. Especially sativa types (have I repeated this?) Watch the very end-tips of the leaves for crunchy browning-that's where nute burn can be seen early on.

Thanks for all the help DH!

I am going to go down to half strength nutes and alternate with plain water for a bit and see how they react.

I will also try feeding the 2 sativa dominates less as well ;)

Here is a pic from today, they do look a little better and the runoff today was 5.5 after a light feeding.

Here's what tip burn looks like. Sorry about the strange lighting effect (leds). Once your tips are crispy, they don't repair; this burn was from weeks earlier. Doesn't really hurt anything (IMO) but it's a sign to back your nutes down. Lotsa folks edge up the nutes till they see this effect, then back down a tad. :D

[attachment=o234129]

Thanks for posting that pic of tip burn dreadedhermie. Once again this forum answers my questions without me having to make a post.

WTF.... how did this thread end up in my newest posts list?