Experienced growers help needed !! Serious chlorosis !

Hi friends, I’m on my knees ! This problem has beaten me so far and ANY help/advice would be hugely appreciated.

I moved to a new indoor grow location some months ago for security reasons after 5+ years happily growing in my original place.

The intention was to grow out some new mothers and use the clones for my grow. The seeds I’m using are C99 f1’s and a cross of c99 x lavender which I created myself. I should point out that the seeds were created outdoors.

New room is 15 ft. x 20ft. Temps. are 25-26 deg. C. Humidity is about 50%. Co2 levels are about 1000ppm, dehumidifier working, fans circulating air. I’ve outfitted the place with 6 x 1000w HPS, but am presently using a bank of 36W daylight acquarium flouros at 4300 lux each for seedlings with the intention to shift the seedlings under one of the HPS when they are 5-6 weeks old. Note that this is my second attempt to grow seedlings here; my first attempt produced plants that were so chlorotic that I dumped them after repeated attempts to cure them.

Right now I’ve 20 new seedlings in 6” pots a couple of weeks old. The soil is virgin Atami janeco light mix NPK 12-14-24. On my previous attempt I used Atami kilo-mix, which is a hotter version of the light mix. The plants are being watered with ph adjusted water. No nutes added. Runoff is about 6.8 ph and EC is about 1.2 mS, a little high but o.k. nonetheless.

The new seedlings are beginning to show signs of leaf chlorosis, from about the third set of leaves. I’m stumped. So what have I tried ?
- Chlorosis, to my knowledge, is caused by several things :
- A nutrient deficiency of either iron, magnesium or manganese. I’ve added a plant ‘tonic’ product last time round which contained chelated iron, mag., and mang. It didn’t make any difference. And why should it ? New soil should have these elements.
- Were my plants overwatered ? No, I let them nearly dry out between waterings and water sinks quickly through the soil.
- Bugs in the soil ? No, checked soil and plant roots. Besides irksome fungus gnats there are no other bugs.
- Maybe I put them under the HPS too early ? That’s possible but then when I backed off the HPS to 4ft. away there was no improvement.
- Maybe the air in the room is bad ? I’ve installed a powerful ventilation system which pumps air in 2 times per day for like, an hour each time.

Now here’s the thing : I decided to take one of the sick plants outdoors. It stayed in the same pot, same soil, the only thing that changed therefore was light, air and water. After 2 weeks of hardening off, hey presto, the plant leapt to life and began to produce green leaves and grow normally.

And heres another thing : I have one of the original chlorotic plants still growing in the room. I kept it to see its evolution over time. Its now grown to three feet and all the new growth is chlorosis free ! WTF ? And here I am……
Some pics below; you can see they are young plants and the chlorosis is obvious. And you may notice that’s its not the normal interveinous chlorosis. The pattern is different; its like chlorophyll destruction.

Guys, if I could call in a pro I would, but for obvious reasons…my eternal gratitude and whatever else I can offer will go to someone who can solve or help me solve this riddle. Its costing me big-time. Uncle Ben, ya out there ? I remember you from many years ago in other places. A true guru….

I Dont have a answer for you just question did it rain at all on the plant you put outside ?

Could it be the PPM of the C02 ?

If you saying it perked up outside then its environmental, too hot too cold, too humid too dry ect.

I would also like to know if it rained while it was outside because that could point to PH issues.

I plant seedlings like that into very hot soil usually the runoff is around 2.4 EC an I never have a problem with burn.

Are you sure it perking up outdoors didnt coinside with a watering ?

Sounds Like a tricky one...

Mouse

My guess would be that the higher values of Co2 mixed with the additional light of the hps made them deficient by growing too fast, they have outgrown their root system.

That would be my guess anyway because otherwise I see no reason for the def you are seeing.

I hope that helps.....

Mouse

Hi, and thanks for your interest. In the hardening off period the plant was sheltered from rain, and when I put it in full sunlight, yes it got some rain but not much.

Co2 must be too strong for them, drop it and see if they recover maybe ? Im not sure.

Mouse

Hi mouse. Good question. I thought about that myself. My new room was a sealed room initially. Got a co2 gen. running producing 1500ppm. With the chlorosis issue on the first run I decided to install a ventilation system for the co2 issue you mention and just in case there was some type of off-gassing from the materials in the room itself. Right now the co2 ppm is 900-1000 and thats with the gen. shut off - city air in summertime can be up to 1000ppm where I live. However the fresh air has failed to revive the plants. Could it be that they've suffered an irreversible blow to their health ? In my experience thats unlikely as you can abuse a cannabis plant a hell of a lot and they recover wonderfully when treated with care.

I explained above that it did rain a little on the plant I put outdoors, however why do you mention ph ? I've measured the runoff ph and its fine. The 'official' ph on the soil bag indicates 5.5-6.5; I'm getting 6.8 or so on my meter. But I ask you the question; if the ph was way off for some reason then the chlorosis would be intervenial. If you look at my pics, the chlorosis I have is not that. It looks like something has destroyed the chlorophyll. You mention the EC of 2.4 you have and I agree with you. 2.4 is pretty hot but the only result of that would be nute burn, not chlorophyll dying.
The plant perking up did not coincide with a watering. In fact I initially suspected a water problem, but during the hardening off process I actually used regular tap water. This plant is now into flowering outside and looks nice.

Thanks again, mouse. As i pointed out in my original post, I'm now starting seedlings once again. I now have fresh air, they're under flouros, watered with ph adjusted water, they're growing at a 'normal' rate, yet if you look at the pic of the young seedling in my post you can already see the beginnings of chlorosis. I guess I'm really hoping that someone has seen the weird chlorophyll deficiency evident in my pics AND has found the reason.

Hmm interesting....

What leads you to believe that PH will always be intervenial chlorosis I was always led to believe that it can manifest as all sorts.

The PPM of Co2 where I am is a lot lower naturally and I dont supplement. Whatever it is i would say its one of the immobile nutrients being at the top of the plant.

But then it got better outside so it would appear to be environmental.

bring it inside but turn the co2 off and see what happens I guess, if you eliminate co2 you are down to it being a soil issue since you havent really fed yet. So then you can eliminate co2 and then repot since it must be a fert issue of some kind and with a small plant that is the easiest solution,

The top of them looks pretty damaged. I really hope they pull back.

I am not sure if I have been of any help but I think its always useful to bounce ideas around.

Mouse

Interesting you should say that the ppm's of co2 might be too much. I always was of the opinion that this 1500ppm 'ideal' for cannabis was unfounded heresay that somehow became gospel in our world. There's no scientific evidence for it that I've ever found, simply anecdotes about how plants grew wildly at such levels. A few botanists that I respect have found ideal levels to be in the 800-1000ppm level. I put my room level at 1500 'just to see' what happens. Now I've backed away from that completely, certainly for young plants. I can imagine a room full of mature plants handling 1500ppm without a problem since they gobble it up so fast that the room is hardly ever at 1500. However there is such a thing as co2 toxicity, but I don't know what the symptoms are.

To answer your direct statement : My gen. is shut off and the fresh air I'm pumping in is at about 900ppm. My breathing while in the room pushes that to 1000 or so. There are plants in soil just outside of my grow and they're fine. My little seedlings are beginning to be chlorophyll-deficient again....

In 25 years of indoor and outdoor growing I've seen several type of chlorosis, most of it interveniously since the majority of problems have been an iron or magnesium deficiency. If nitrogen is the problem then yes, the chlorosis looks different, or something preventing Calcium uptake. But look at my type of chlorosis...is it even that ? I've never seen what I have now and I've seen hundreds of sick plants in my time.

As you say, the plant brought outside got better, so its light or water or air. This is the reason on my second run I'm using exclusively flouoros for at least 5 weeks, co2 shut off with fresh air being pumped in, AND I'm using imported water from another location, ph adjusted. In fact on reflection I may just go with straight tap water to eliminate also the ph down i'm using (phosphoric acid). The unadjusted ph of the water is 7.6; not ideal but ok for a test.

Thanks for yr. i/p mouse. Yes, you've been very helpful ! You agree with me thats its most lightly environmental - I needed somebody to agree with me on that ! Cheers man.

mouse said:

Hmm interesting....

What leads you to believe that PH will always be intervenial chlorosis I was always led to believe that it can manifest as all sorts.

The PPM of Co2 where I am is a lot lower naturally and I dont supplement. Whatever it is i would say its one of the immobile nutrients being at the top of the plant.

But then it got better outside so it would appear to be environmental.

bring it inside but turn the co2 off and see what happens I guess, if you eliminate co2 you are down to it being a soil issue since you havent really fed yet. So then you can eliminate co2 and then repot since it must be a fert issue of some kind and with a small plant that is the easiest solution,

The top of them looks pretty damaged. I really hope they pull back.

I am not sure if I have been of any help but I think its always useful to bounce ideas around.

Mouse

Click to expand...

sorry, didn't answer that suggestion : No can do now as i've put the plant in the ground, its outdoors 12/12 time, and she's flowering nicely. Besides I can't go to 12/12 indoors right now - only one room to work in presently and I'm occupired with my new seedlings.

Sorry man, I answered you ages ago but it seems to have got lost....

Did I imply that pH exclusively causes interveinal chlorosis ? Sorry. 'Didn't mean to say that. What I meant to say was that a seriously out-of-range pH can cause nutrient lockout, such as the nutrients responsible for chlorophyll.

You'd probably find the co2 ppm in your living area is around 1000ppm if you share it with several other people. Anyway yeah, the problem is environmental. Water, light, heat, air. The plant was crappy indoors and thrived outdoors. I'm pretty confident my heat (25 deg. C) is fine. Same with my air with a 720m3 /hr. inlet fan. That leaves the light and water. Presently I'm in the process of testing the water by using stuff from another source.

Can't bring her inside anymore. She's in the ground in full bloom right now so I'm not disturbing her ! Anyway I don't think it is a co2 issue. I pump in lots of fresh air for the small amounts of plants in the space. Soil issue ? Nah. I know this soil for years and it measures fine. Its down to light or water. For me its got to be the water, UNLESS, I've somehow bleached the leaves with excessive light.

I've also looked closely at the affected sites on the leaves, and it is more bleaching than a uniform chlorosis. Strange. The plant tissue is white, veins included, with a slow migration to green in some parts. Its not chlorosis, but I don't know of any other way to describe it.

Any other advice/opinions......an environmental problem ?

Could be bleaching if the plant wasnt hardened off enough. I am really sorry I cant be of assistance on this one. I am just trying to throw ideas at you.

Now one thing is that now for the first time in a long time you are dealing with seedlings and they are very fragile. I mean some of my clones are old plants by the time they have rooted. They are pre hardened and conditioned to take your environment. Maybe the seedlings cant deal with that environment just yet.

I just had to back my 250 watt cfl off by over a foot for my seedlings and I was sure I could have them almost touching and my mother and clones are perfectly happy to be almost touching, the seedlings are not happy being that close to the light.

Sounds like over developed tops and under developed roots. putting them outside gave them time to catch up.

Ahh the ramblings of a stoner.

I guess at this point its back to basics. Have you changed soil supplier ?

Whats the PPM of your base water ? do you leave it for 24 hours ? do you have a different water supplier since you moved ?

God knows. Now I am just vying for ideas he he.

Mouse

BTW if it is a root mass issue ( just a guess) House and Garden Roots Excel is the bomb !

Mouse

mouse said:

Could be bleaching if the plant wasnt hardened off enough. I am really sorry I cant be of assistance on this one. I am just trying to throw ideas at you.

Now one thing is that now for the first time in a long time you are dealing with seedlings and they are very fragile. I mean some of my clones are old plants by the time they have rooted. They are pre hardened and conditioned to take your environment. Maybe the seedlings cant deal with that environment just yet.

I just had to back my 250 watt cfl off by over a foot for my seedlings and I was sure I could have them almost touching and my mother and clones are perfectly happy to be almost touching, the seedlings are not happy being that close to the light.

Sounds like over developed tops and under developed roots. putting them outside gave them time to catch up.

Ahh the ramblings of a stoner.

I guess at this point its back to basics. Have you changed soil supplier ?

Whats the PPM of your base water ? do you leave it for 24 hours ? do you have a different water supplier since you moved ?

God knows. Now I am just vying for ideas he he.

Mouse

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Well yeah, I haven't dealt with indoor seedlings in years but I do grow outside as well and I ALWAYS go with seeds in the late Spring 'cause I like to grow out different stuff to my CC indoors.
And you're right about the root mass on my sick babies; its pretty thin but thats due to the chlorosis/ no light synthesis I would have thought.
EC of base water is 0.5 mS (250 ppm ?). Yeah, its in a tub for 24 hours. As part of eliminating water as the problem I'm bringing in water from another grower I know to be good.

'Been looking around and see that the Tobacco Mosaic Virus (TMV) and the Hemp Streak Virus (HSV) cause similar symptoms to what I have. I know nothing about viruses in MJ and I HOPE it isn't that, but hey, you said it yourself, its environmental. Plants did poorly indoors and very well outdoors and the only things that changed were light, temps., air and water, since I'm using another water supply for outdoor plants.

I hope your lil ones pull through anyway.

Mouse

mouse said:

BTW if it is a root mass issue ( just a guess) House and Garden Roots Excel is the bomb !

Mouse

Click to expand...

Yeah okay, but it doesn't solve the basic problem of why the root mass is thin in the first place. What do you think about trying foliar feeding ? IF the plants absorb and use nutrients through the leaves then that might tell me something..

You could I guess it wouldnt do any harm at this time. I usually foliar small plants with a mild rhizotonic solution. Works good for me. I use Magic green on vegging plants and HALO on flowering ones.

I still have this nagging thing in my head that says its nutrient or dirt related. Give them like 1 CFL and no Co2 for a few days and see if they perk up ?

Just keeping the ideas flowing....

Mouse