Deficiency/toxicity? - Tha Shiznit Autoflower

SickSickWorld

SickSickWorld

Well-Known Member
Hello, wondering if anyone could shed a little light on my problem.

I'm currently growing Short Stuff Tha Shiznit (journals on here), 13 days since sprout, and on Sunday see started showing a few signs of a possible deficiency/toxicity.

The problem area is currently just localised too the first, oldest two leafs, but I'd like to nip this in the bud (ha) sooner rather than later, before it affects any newer growth.

She's been growing in BioBizz Light Mix, and fed dechlorinated tap water only. I have nutes on hand, and she's due a water today so could feed of needed. Someone suggested a possible potassium deficiency, and I'd be inclined to agree, but I'd appreciate any advice.
 
JohnySmith1

JohnySmith1

Well-Known Member
The picture of the whole plant would be useful. However, with the auto flowering genetics deficiency happens very rarely. If its toxicity and you increase the PPM concentration in your medium, the plant may die in no time. I suspect a toxicity as the dark green colour of the leaves indicates the excess of nitrogen in the medium. I suggest, collecting some run off by giving your plant a plain tap water (dechlorination is unnecessary as concentration of chlorine in tap water is minimal and a little chlorine won't harm, instead it will be supportive ) take a probe with your TDS/PPM meter and let us know what the reading are.
 
SickSickWorld

SickSickWorld

Well-Known Member
JohnySmith1 said:
The picture of the whole plant would be useful. However, with the auto flowering genetics deficiency happens very rarely. If its toxicity and you increase the PPM concentration in your medium, the plant may die in no time. I suspect a toxicity as the dark green colour of the leaves indicates the excess of nitrogen in the medium. I suggest, collecting some run off by giving your plant a plain tap water (dechlorination is unnecessary as concentration of chlorine in tap water is minimal and a little chlorine won't harm, instead it will be supportive ) take a probe with your TDS/PPM meter and let us know what the reading are.
Click to expand...
Cheers man. I'm currently awaiting delivery of a ppm meter, so I'm a little in the dark until then.

Pictures of the whole plant can be found on my journal, I didn't want to flood the forums with photos of my plants! Haha

http://rollitup.org/t/first-grow-auto-ultimate-tha-shiznit.901185/page-4#post-12415007

The soil is supposedly a very light mix, only thing added to it is perlite and tap water, so I'm a touch confused. Nitrogen toxicity has been mentioned previously, she is rather dark, but other than water I'd have no idea where its coming from. Would it be worth flushing with bottled water until I get my ppm meter? I'll take some more photos in the next half hour-forty five minutes.
 
JohnySmith1

JohnySmith1

Well-Known Member
definitely no fertilizers, use water only, until you see plant starts to turn light green color. According to its current color, it suffers from nitrogen toxicity. Just keep an eye on cal/mag deficiency.
 
SickSickWorld

SickSickWorld

Well-Known Member
JohnySmith1 said:
I suppose this is an autoflowering genetics?
Click to expand...
Yes, Short Stuff Seeds Tha Shiznit.

Like I say, do you think its worth trying to flush the soil with the next watering? I can't wait to get my ph and ppm pens.

I'll look into, and keep my eye on, cal/mag deficiency.

Thanks a lot man, big help.

Sick
 
tipper01

tipper01

Well-Known Member
flush how you not added anything as yet have ya i thought u was using straight water first few weeks , im hoping to get through to floweer with no nutes
 
JohnySmith1

JohnySmith1

Well-Known Member
SickSickWorld said:
Yes, Short Stuff Seeds Tha Shiznit.

Like I say, do you think its worth trying to flush the soil with the next watering? I can't wait to get my ph and ppm pens.

I'll look into, and keep my eye on, cal/mag deficiency.

Thanks a lot man, big help.

Sick
Click to expand...
It's an organic soil, I would not flush it as you may disturb some important biosynthetic processes and stunt the plant for a while. Just give it water and let soil dry out before every watering and it will do fine! I don't have any experience with biobizz but in plant magic soil the runoff pH indicates 5 from the beginning of the growth to the end but in reality, the pH in soil totally different and these effect occurs due to buffers used in the mix. I am just saying if you probe runoff pH and you won't like it don't do anything unless pH problems are visible on the plant.
 
yeatster

yeatster

Well-Known Member
My understanding is that the mix of perlite and biobizz light would be very light in fertilizer.
How could there be a toxicity?
The dark green sure looks like N toxicity to me.
But the discolored leaf looks to be a deficiency.
I am confused with this and really hope there to be a confirmation.

Me, personally, I would give it a feed of 1/4 strenth nutes, hoping it stopped the discoloring of the leaves.
He has been giving it straight water, no nutes, and says it is progressing.

????

Edit: symptoms are "progressing"
 
Last edited:
SickSickWorld

SickSickWorld

Well-Known Member
Thanks guys. Appreciate the input. I'll continue to water sparingly as normal, and keep tabs on the issue. Hopefully, she lightens up a touch, and things turn out alright!

No, she's not been fed anything. I just thought if there was a nitrogen excess in my soil, flooding it with 3x volume water would help pull a but of that out. If not, them I won't!
 
JohnySmith1

JohnySmith1

Well-Known Member
yeatster said:
My understanding is that the mix of perlite and biobizz light would be very light in fertilizer.
How could there be a toxicity?
The dark green sure looks like N toxicity to me.
But the discolored leaf looks to be a deficiency.
I am confused with this and really hope there to be a confirmation.

Me, personally, I would give it a feed of 1/4 strenth nutes, hoping it stopped the discoloring of the leaves.
He has been giving it straight water, no nutes, and says it is progressing.

????
Click to expand...
Good question mate, light mix is a very relative meaning. It's might be light for some huge tomato plants but not for auto genetic cannabis.
According to the manufacturers concentration of fertilizers in the mix is at 1.2 EC which is equivalent to 600 PPM and for auto genetics is a toxic concentration. It's a known fact that auto flowering plants are light feeders that means most of their mass is coming from conversion of CO2 by photosynthesis and only a fraction of it from the soil. The symptoms of toxicity may get worse for the while concentration sets for the plant requirement.
 
yeatster

yeatster

Well-Known Member
Sick failed to mention he has also added 30% perlite, according to his journal.
That would theoretically change the ec. to .8 from 1.2, correct?

If what Pioneer says is correct, seedlings needing .6, then is .8 enough to cause toxicity?
 
JohnySmith1

JohnySmith1

Well-Known Member
yeatster said:
Sick failed to mention he has also added 30% perlite, according to his journal.
That would theoretically change the ec. to .8 from 1.2, correct?

If what Pioneer says is correct, seedlings needing .6, then is .8 enough to cause toxicity?
Click to expand...
No, perlite do not dilute the concentration of fertilizers in the mix, all it does is reduces the surface area. It means there fewer fertilizers according to weight but they released and absorbed at the same rate (1.2 EC).
 
You must log in or register to reply here.
Top