Problem(s) need some advice please

[Cachagua]

Below is an image of one of my gals leaves.
This is from a SuperCanalope and is about 3 weeks into 12/12.
I started downward from 18hrs/day of light to 12/12 over a 15 day period.
They all reached 12/12 on 10/26/09 so that's about 3 weeks ago.
I have 2 SuperCanalope females, the one the leaves in this picture come from has been struggling, in fact It was not until about a week ago that I was sure she was even female.
The other SuperCanalope female as well as the others varieties in my harem are all doing fantastic, and in fact are in full flower now.
This one is just now starting to reach heavy pistil development/pre flower.

All of my plants are indoor soil cultivation.
Soil was hand mixed using a combination of FFOF, Black Gold, small amounts of blood meal, bone meal, hydrated lime, kelp meal.

Soil PH when these plants were all placed into this soil mix was 6.8 and continues to hover between 6.2 and 6.8 depending on nutes.
I have always ph'd the nute mix prior to watering my plants, and the ph of my nute solution is between 6.0 and 6.5

Runoff ph is always right between 5.9 and 6.4 ph, again depending on nute s used.

I have NEVER used full strength nutes yet, and my primary nute additive to date has been Flora Nova Bloom (1 part) liquid.

Now on to the problem at hand, but before that, let me clarify.
This plant is the ONLY plant in the harem that has a single problem, the rest look healthier than I have ever seen any plants look, they look fantastic, are huge and all sport large healthy fan leaves.

The plant in question has had this problem going on about 2 weeks now.
It started with one of the lower leaves turning yellow and then getting dark green spots which are surrounded by dark brown or bronze circles.

I initially thought nitrogen deficiency so I added a little (1/4 strength) FF Grow Big to a gallon of water, then ph corrected the mix and fed the plant.
Nothing changed over the next few days so I stuck with a water only regimen for the next 3 waterings.

More and more of the lower smaller leaves started to show signs of this malady, so I referred to the pictorial here on 420 and zeroed in on a possible manganese deficiency and added small amount (1/4 strength) of Big Bloom and Open Sesame which have manganese.

Anyway, fast forward to today, I have foliar fed with Cal Mag plus, my regular nute and seaweed extract to no avail, the leaves continue to yellow, then develop dark green spots, then die at the tips and eventually fall off.

Whats happening here? does anyone want to take a shot at this one?

 

[Be Irie]

how about a pic of the whole plant.. It looks like a nitrogen problem... You are using soil, you don't have the fast turn around like you would hydro... It takes a little bit of time to correct itself. Your leaves wouldn't heal either.. Why wouldn't you go full strength??

 

[Cachagua]

Hey Irie,
Thanks bro,
I decided NOT to go full strength because I believe my last grow resulted in seriously stunted and locked out final product due to over fertilizing.
This time I decided to try and add nutes very slowly throughout the flowering period.

I was also looking at Boron being a possible problem with this plant? Nitrogen generally only shows premature yellowing and dying off does it not?
I had no idea Nitrogen would also show the spotting and necrosis of the tips?

 

[Be Irie]

it's hard for me to say with just pics of leaves..Were those the only two that did it.. Any others showing signs of the same thing? I think the necrosis at the tips is just the next stage of dying off...With the low nutes it actually could be a combo of a few things.. Maybe someone else will chime in...

 

[Cachagua]

it's hard for me to say with just pics of leaves..Were those the only two that did it.. Any others showing signs of the same thing? I think the necrosis at the tips is just the next stage of dying off...With the low nutes it actually could be a combo of a few things.. Maybe someone else will chime in...

No those were not the only 2 that did it, this started at the bottom of the plant about 2+ weeks ago and has started to work it's way up the plant now.
It has progressed to about half way up the plant at this point.
To date, I have probably lost about 25 leaves from this plant.
Mostly smaller lower leaves but now the larger fan leaves are starting to show signs of the same problem.

 

[BWC BayArea]

Maybe its a fungus if it rapidly destroyed a large part of the plant. Also adjacent plants would be affected as well in a similar fashion. Pics of the plant affected and surrounding plants would help.

 

[Cachagua]

Maybe its a fungus if it rapidly destroyed a large part of the plant. Also adjacent plants would be affected as well in a similar fashion. Pics of the plant affected and surrounding plants would help.

No fungus, the box is so well ventilated it is silly.
None of the other plants are affected, they all look exceptionally healthy except for the lower leaves on one plant where I had a blow out with the wet/dry vac and sucked up a branch and destroyed a couple of leaves which are now in rehab.

Obviously these are lights on pics with the usual color blow out, even thought I did a quick once over with them in photoshop, this is as good as it gets in a hurry.

As I mentioned, none of the other plants are affected.
This particular plant always looks a little droopy compared to the rest of them, however she is among the tallest of them all.

These are all extremely leggy sativas, so any leaf loss makes them look exaggeratedly anemic from what I can tell, but again none of the other plants are affected.

The plant directly behind the one in question is the same variety (Super Canalope) and was germinated on the same day, planted the same day in the same batch of soil.
The other (non affected one) is much more robust looking, started budding much sooner, and has much broader fan leaves, and a far deeper green overall color.

Best I could do with the lights on fellas, let me know what you think.

THIS IS THE SISTER TO THE AFFECTED PLANT:

 

[BWC BayArea]

No Fungus?

Seen it b4. Not sure I properly diagnosed when I had the problem. I'll be watching to see how this unfolds. And for the record u can have all of the ventilation in the world (although it does help decrease ur chances), fungus can and will grow. Some spores are pretty much ubiquitous. The main things are temp and humidity.Consider this, cannabis is grown outdoors every year. Every year growers get have mold problems, they're outside with all of the wind they can handle and then some. Wind=ventilation. Being that its only affecting one plant, I like u am less inclined to believe this is a fungal problem unless it spread to ur other plants. Good luck.

 

[Cachagua]

BWC, can ya tell me what it is?
Anyone? I need some help with this one, I don't want to just let her rot away.

 

[BWC BayArea]

I gotta do some research. I saw that last year some time. Forgot what it was. All I know is that I finished with no fan leaves (there were a few that made it to harvest). Bud was good tho. I'll try and get back to u on this one. I gotta check some things. Until we figure this out do you have a tent or another room to keep it (quarantine) separate in case it is something the others can catch? Just a precaution. Also lets talk environmental controls. What are ur temps and humidity like? Is ur intake air filtered? I noticed the vent almost directly in front of the pot. I was thinking it maybe yellow leaf spot AKA ''leaf septoria". The septoria fungi is said to be pretty much ubiquitous (everywhere). They just need the right conditions to grow. The control for this are to remove infected leaves and to spray with neem or copper fungicides to slow its progression. U can also burn sulfur. I've kinda exhausted my personal resources and I'm stumped. I PMed some reinforcements. I'm sure when they have time they will stop by to lend their more experienced/expert opinions. Hopefully we can get to the bottom of this soon. Until then, I'm waiting like u are Cachagua.

 

[Cachagua]

Thank you bro,
I am heading into the room right now as the lights jut came on.
I did a full feeding with the heavies nitrogen rich nute I have which is Grow Big.
I went full strength with it yesterday so I am going to have a look tonight and see if there is any improvement.
Thanks for the heal BWC, I appreciate it bro!

 

[BWC BayArea]

Did u flush ur medium before feeding? Please consider this b4 feeding. Also excess nitrogren (during bloom) can promote powdery mildew growth according to Jorge Cervantes author of the MMJ indoor/outdoor Grower's bible.

 

[Cachagua]

No, I did not flush, however, whenever I water, I follow the 20% runoff rule and they have been on straight ph'd water for several days prior to last nights feeding.

This was the first full strength dose of anything they have ever had.
Every other time I fed them was with Flora Nova at less than half strength.

I have probably starved these plants more than they need to be, really trying not to be nute heavy with this run, mainly trying to manage ph since they are in 3 gal containers which seems to make it harder to keep ph relatively stable..

They all looked like they could use a little shot of nitrogen but I will not use anymore after this. from here on out they are going to get bloom nute quantities of npk.

 

[BWC BayArea]

Try feeding full strength to one pot 1st and see how it reacts. It is a risk if u've never hit them with full strength b4. Did u feed them a transitional nute mix between veg and flower?

 

[Irish]

It's hard to tell from just pics, but does this malady happen just on particular stems/branch systems, or is it random all over the plant? You might be having a problem in your roots if it is confined to particular branches. Other than that little snippet of input though, I got nuthin', other than the plant is traumatized, and appears to be traumatized in some areas and not others. Unless something got accidentally sprayed on those areas to cause this, I'm gonna go with roots. Perhaps something is attacking her root system a root at a time so that she cannot draw in her proper uptake from those areas, which would manifest directly through what part of the plant is reacting adversely. This would make sense only if the problem presents on a per-branch basis. Random, and I just got nuthin'....

 

[BWC BayArea]

It Sure Can't Hurt

Since u haven't flushed, lets stop speculating and start there. After flushing in soil it takes a a while to see the beneficial effects (unlike hydro). Flush all pots with this problem and observe them next to the others. If the problem persists after flushing then we have to figure something else out. Flushing, when done correctly shouldn't harm ur plants. I have another idea if that doesn't work.

 

[McBudz]

Re: It Sure Can't Hurt

Since u haven't flushed, lets stop speculating and start there. After flushing in soil it takes a a while to see the beneficial effects (unlike hydro). Flush all pots with this problem and observe them next to the others. If the problem persists after flushing then we have to figure something else out. Flushing, when done correctly shouldn't harm ur plants. I have another idea if that doesn't work.

I agree, clean slate if its a nutrient/lockout/ph type issue. Flush for a week and adjust pH accordingly. Runoff should be 6.3-6.7. then go back to known good nutrient regimen. Like Irish said it would be nice to know if this is isolated to certain part of the plant like 1 or 2 branches. I've never seen anything like those black spots. Does it look like necrotic leaf or something like a mildew or mold on the leaf? Hard to tell from the pics. If its something on the leaf I would remove the plant for fear it may effect the rest of the crop. Must do what's best for the whole garden.

 

[Cachagua]

OK here is an update.
I have removed the plant from the main grow box.
It is now under the CFL's in my veg area which is currently running 12/12 and is home to my hermie'd Durban Poison which is in full flower right now.
Had to keep the Durban Poison because it is 99% female and is in full bud bloom right now.....none the less the plant in question is isolated from the main flower room.

To answer some of the questions:

(1) it is not isolated to one part of the plant, it seemed to start at the bottom, with the biggest fan leaves first, then moved up the plants to the smaller leaves. Every part of the plants lower stem structure had leaves affected in this way.

(2) Soil and runoff PH is consistent with the rest of the plants in the harem.

(3) It does not look like mold or mildew at all.
The spots are very very dark green with a brown border around the dark green portion. Something I have never seen in ANY picture on any website.
When you look at the bottom of an affected leaf, those same circles or dark green are not as noticeable, yet they can be seen because of the semi translucent nature of the leaf itself if that makes any sense.

(4) BEFORE the affected leaves start to die at the edges or tips, but when they turn completely yellow and spotted, if you just so much as touch the leaf, it drops off of the plant, in fact if you blow on it hard enough it comes off.

So when you say flush for a week, are you saying flush with plain water? or use a flushing agent?

 

[Irish]

Exploring bacterial diseases of tomatoes today uprooted this page:

Bacterial spot of tomato

Bacterial Spot
Bacterial spot is caused by Xanthomonas campesiris pv, vesicatoria. It is periodically a severe disease of tomatoes and sweet peppers in New York. Because bacterial spot and speck produce similar symptoms, they are often misdiagnosed.

Symptoms
Infected leaves show small, irregular, dark lesions (fig. 6), which can coalesce and cause the leaves to develop a general yellowing. Both spot and speck can occur on stems and petioles where they are indistinguishable. Flower infection with bacterial spot can be quite serious with pedicel (fig. 9) infection causing early blossom drop. The two diseases are most readily distinguished on the basis of fruit symptoms. In the case of bacterial spot on green fruit, small water-soaked spots are first noticed (fig. 7). These spots become slightly raised and enlarge up to 1/8 to 1/4 inch in diameter (fig. 8). The center becomes irregular, brown, slightly sunken, with a rough, scabby surface. Although ripe fruit are not susceptible, lesions are very obvious if fruit were infected when green.

(Bacterial Diseases of Tomato Fact sheet)

 

[Flurple]

good luck with the plant, i dont have any new info for ya.