Effect of deficiency on flowering

kryptoniteglo

kryptoniteglo

Well-Known Member
Hey Learned Folks at RIU,

I have a God's Gift finishing week 6 of flowering and it's showing what seems to be either a Potassium deficiency of a Manganese deficiency -- largest fan leaves overnight turned light green about a week ago and now are yellow with blotches.

I'm in hydro, AN 3-part system, ppms averaging 600-700. Ph with this plant has always been low, sometimes down to 4.9 or 5.0, and I've brought it up to 5.9 once a day. In the last week, the Ph has stabilized well, and while the plant is drinking a lot, it's not taking up as much nutes.

A Pennywise growing under the same conditions in a separate bucket a foot away is completely normal. I'm expected her to finish in the next two weeks.

The God's Gift, however, has 2-3 weeks to go.

So my questions:

What will the effect of this deficiency be on flowering? And is it worth ordering and buying specific nutes to add, given that I'm 2-3 weeks way from finishing and I've never had this problem before and may never again?

Thanks!
KG
 
jondamon

jondamon

Well-Known Member
kryptoniteglo said:
Hey Learned Folks at RIU,

I have a God's Gift finishing week 6 of flowering and it's showing what seems to be either a Potassium deficiency of a Manganese deficiency -- largest fan leaves overnight turned light green about a week ago and now are yellow with blotches.

I'm in hydro, AN 3-part system, ppms averaging 600-700. Ph with this plant has always been low, sometimes down to 4.9 or 5.0, and I've brought it up to 5.9 once a day. In the last week, the Ph has stabilized well, and while the plant is drinking a lot, it's not taking up as much nutes.

A Pennywise growing under the same conditions in a separate bucket a foot away is completely normal. I'm expected her to finish in the next two weeks.

The God's Gift, however, has 2-3 weeks to go.

So my questions:

What will the effect of this deficiency be on flowering? And is it worth ordering and buying specific nutes to add, given that I'm 2-3 weeks way from finishing and I've never had this problem before and may never again?

Thanks!
KG
Click to expand...

Could you post a few pics of effected leaves and whole plant.

It could be that K has become toxic or it could just be a late stage Mg deficiency.


Pics would most DEFINATELY help.



J
 
kryptoniteglo

kryptoniteglo

Well-Known Member
Ok, posting three pics.

The first is of the faded leaves -- about a week after I first noticed they were suddenly very pale light green. It happened overnight.
 

Attachments

kryptoniteglo

kryptoniteglo

Well-Known Member
And the third pic of the whole plant. The top cola on the left has curled down leaves because there was more than a 3x stretch and the damn thing grew past the light.
 

Attachments

kryptoniteglo

kryptoniteglo

Well-Known Member
Again, looking for 1) a diagnosis since I've never had this happen before and 2) advice on whether to do something about it or just let her ride for the next 2-3 weeks until harvest.

Thanks!
 
kryptoniteglo

kryptoniteglo

Well-Known Member
jondamon said:
Have you been using a PK booster excessively?


J
Click to expand...
Nope -- I'm a minimalist grower. I use the very basic 3-part Advanced Nutrients, plus a little bit of cal/mag because my water's natural ppm is 40. No boosters. Ppms are 600-700 on this grow. And the Pennywise next to it in its own res is absolutely normal. They've finished week 6 of flower as of today, but it might be closer to 6.5 since it's really 8 since the flip. They took about 10 days to show female. The Pennyswise is just showing a slight color change on her leaf tips -- her fade is about to start.

But here's a thought. The God's Gift was a VERY light feeder in veg. I mean 450-500 was all it could take. Then it seemed to be able to take more, so I brought her up to 600. Then this business on her fan leaves started, and I assumed it was a deficiency. So I figured I was lightly feeding in general, and brought her up to 700 to give her a little extra.

If you think this is toxicity, then maybe I should have kept her at 450-500 all along????

Thoughts on that?
 
jondamon

jondamon

Well-Known Member
kryptoniteglo said:
Nope -- I'm a minimalist grower. I use the very basic 3-part Advanced Nutrients, plus a little bit of cal/mag because my water's natural ppm is 40. No boosters. Ppms are 600-700 on this grow. And the Pennywise next to it in its own res is absolutely normal. They've finished week 6 of flower as of today, but it might be closer to 6.5 since it's really 8 since the flip. They took about 10 days to show female. The Pennyswise is just showing a slight color change on her leaf tips -- her fade is about to start.

But here's a thought. The God's Gift was a VERY light feeder in veg. I mean 450-500 was all it could take. Then it seemed to be able to take more, so I brought her up to 600. Then this business on her fan leaves started, and I assumed it was a deficiency. So I figured I was lightly feeding in general, and brought her up to 700 to give her a little extra.

If you think this is toxicity, then maybe I should have kept her at 450-500 all along????

Thoughts on that?
Click to expand...

How has the res been reading every 24 hours?

Any massive drops in ppm or massive increases in ppm?

I know your pH had been dropping quite drastically down into the 4's which could have possibly caused issues up taking N, P, K, Mg, Ca and B.

With Mn and Fe still available.


The more I look at your pics the more I'm thinking possibly Ca def symptoms.



J
 
Maris

Maris

Member
if you have kleft just 2-3 weeks before harvest hmm. give more pottasium and phosphorus next 1week and then stop everything fertilizer. I think you dont need much worry about that if you say right no more 3 weeks before harvest.
 
kryptoniteglo

kryptoniteglo

Well-Known Member
jondamon said:
How has the res been reading every 24 hours?

Any massive drops in ppm or massive increases in ppm?

I know your pH had been dropping quite drastically down into the 4's which could have possibly caused issues up taking N, P, K, Mg, Ca and B.

With Mn and Fe still available.


The more I look at your pics the more I'm thinking possibly Ca def symptoms.



J
Click to expand...
Typically this res has been reading 650-700ppm, ph 5.9 -- for about the last week. Prior, it would be 650-700ppm, ph 5.2 (or as low as 4.9) and I'd have to bring it up. This plant for some reason had massive ph drops for the first 4 weeks of flower. I've never used more ph up than ph down before, but for some reason on this plant in this grow, that's all I've used!

Not being sure, I just did a full res change, lowering the ppms to 500. I knew this plant was a light feeder in veg and maybe that's still the same, except for the first 3 weeks of flower when it was taking up a lot of nutes.

I'm going to add a little more cal/mag to boost that, as per your thoughts.

One thing I did notice was the AN changed the composition of its nutes in this line last year -- the current ratio of NPK is 6-4-10, when in the past it was more like 6-5-5, or something like that.

It doesn't seem to matter for the Pennywise, but the God's Gift might be a lot more sensitive.
 
kryptoniteglo

kryptoniteglo

Well-Known Member
Maris said:
if you have kleft just 2-3 weeks before harvest hmm. give more pottasium and phosphorus next 1week and then stop everything fertilizer. I think you dont need much worry about that if you say right no more 3 weeks before harvest.
Click to expand...
Yeah, I don't think it's a TOTAL disaster at this stage, but I'm definitely curious about what it could be so I can avoid it next time if possible. This last week the plants aren't really taking up nutes at all, which is pretty typical in the last couple of weeks. For the last few days I've been adding only water. I'll add a little more phosphorus, though to see if that just stabilizes the girl for her finish.
 
Maris

Maris

Member
of all deficiencys its a closer description. But you know better I just see few leafs in your pics.I think its this:
When your plants are deficient in phosphorus, this can overall reduce the size of your plants. Not enough causes slow growth and causes the plant to become weak, to little amount of Phosphorus causes slow growths in leaves that may or may not drop off. The edges all around the leaves or half of the leaves can be brownish and work its way inwards a bit causing the part of the leaves to curl up in the air a bit. Fan leaves will show dark greenish/purplish and yellowish tones along with a dullish blue colour to them. Sometimes the stems can be red, along with red petioles that can happen when having a Phosphorus deficiency. This isn't a sure sure sign of you having one though, but can be a sign. Some strains just show the red petioles and stems from its genes.
So pretty much the overall dark green colour with a purple, red, or blue tint to the fan leaves is a good sign of a Phosphorus deficiency. Having Cold weather (below 50F/10C) can make phosphorous absorption very troublesome for plants.
 
kryptoniteglo

kryptoniteglo

Well-Known Member
Maris said:
of all deficiencys its a closer description. But you know better I just see few leafs in your pics.I think its this:
When your plants are deficient in phosphorus, this can overall reduce the size of your plants. Not enough causes slow growth and causes the plant to become weak, to little amount of Phosphorus causes slow growths in leaves that may or may not drop off. The edges all around the leaves or half of the leaves can be brownish and work its way inwards a bit causing the part of the leaves to curl up in the air a bit. Fan leaves will show dark greenish/purplish and yellowish tones along with a dullish blue colour to them. Sometimes the stems can be red, along with red petioles that can happen when having a Phosphorus deficiency. This isn't a sure sure sign of you having one though, but can be a sign. Some strains just show the red petioles and stems from its genes.
So pretty much the overall dark green colour with a purple, red, or blue tint to the fan leaves is a good sign of a Phosphorus deficiency. Having Cold weather (below 50F/10C) can make phosphorous absorption very troublesome for plants.
Click to expand...
Interesting what you say about leaves dropping off or not dropping off. I have noticed that in 5.5 weeks of veg, 2 weeks of transition and now 6 weeks of flowering not a single leaf has dropped off these plants! NOT ONE. Usually at least a few start dropping by now...

Grrr…I hate it when the nutes companies change things! You dial in your grow and then you're suddenly dealing with a curve ball.

Ok, going to ride this one out and rethink my nute strategy for the next grow. I'm not throwing out what I have, but I'll rework the proportions.

Thanks!
 
kryptoniteglo

kryptoniteglo

Well-Known Member
Just a follow up here -- after the full res change, the ph has now stabilized or rises a little which seems more normal to me, as opposed to dropping a lot every day. Also she's taking up nutes again. I think God's Gift is a little finicky -- she seems to need light feedings but more regular res changes to rebalance all the nutes in the res.

Thanks for your help!
 
Last edited:
You must log in or register to reply here.
Top