Does old growth naturally yellow ?

Just had a quick question.
I have two plants that are in the first week of flowering. I switched to 12/12 exactly 5 days ago. Before switching, I noticed that leaves on the lower branches were yellowing and dropping off starting with fan leaves. I lollipopped them a few days before I switched because they didnt receive much light anyway and figured that could be the issue. The top canopy still seems healthy I just want to make sure it won’t progress.

Is it normal for them to yellow if they receive little light? Should I look out for something else?
Before switch I used General Organics BioThrive Grow (1/4th dose) about once a week. Since switching they’ve been given 1 watering with BioThrive Bloom (again 1/4 dose).
Soil is FFSF.
Light is WILLS 600w full spec LED with both Veg and Bloom switches on. Unrelated question, should I only use the Bloom switch on the light?

Thanks!

The beginning of a nitrogen deficiency. Yellowing starts at the bottom and works upwards.

I mean, yes, leaves will do this, especially if they are down at the bottom where there's not enough light. But I agree it does look like maybe a little light on the nutes... Overall light green and fading too soon... How big is that pot?

hawse said:

I mean, yes, leaves will do this, especially if they are down at the bottom where there's not enough light. But I agree it does look like maybe a little light on the nutes... Overall light green and fading too soon... How big is that pot?

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Renfro said:

The beginning of a nitrogen deficiency. Yellowing starts at the bottom and works upwards.

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It’s a 5 gallon bucket. And I’ve posted my issues on here earlier and the plant curled and looked nitrogen tox so I had to flush these plants. Have used the nutrients very sparingly since. I’ve fed a light dose 3 times since the flush which was a little over 2 weeks ago (aug 9th). The leaves are down at the bottom getting very little light and I try to do tie downs to get them more. Losing the fan leaves is unsettling especially going into flowering. Hesitant to give too much nitrogen again I believe the soil was hot to begin with. I have the veg nutes (4-3-3) or bloom (2-4-4) that I could give next watering. Also a calmag supplement (2-0-0)

Cwmoore577 said:

the plant curled and looked nitrogen tox so I had to flush these plants. Have used the nutrients very sparingly since

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I saw the clawed leaves from your excess nitrogen adventure. As the plant gets bigger it's need for feed increases. You just need to find the sweet spot.

Did you drill holes in that bucket? I don't see any kind of drip tray or saucer. Also looks like you have nice hardwood flooring that I would want to protect. On another note, listen to Renfro, I'm still a rookie.

Renfro said:

I saw the clawed leaves from your excess nitrogen adventure. As the plant gets bigger it's need for feed increases. You just need to find the sweet spot.

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Ok, thanks I’ve definitely got to keep learning. Since I just switched them to flower should I give some of the 4-3-3 nutes or the 2-4-4?

PadawanWarrior said:

Did you drill holes in that bucket? I don't see any kind of drip tray or saucer. Also looks like you have nice hardwood flooring that I would want to protect. On another note, listen to Renfro, I'm still a rookie.

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Yes there are drainage holes. Also the trays are in the tent I pulled them out just to get decent lighting for pictures.

Cwmoore577 said:

Ok, thanks I’ve definitely got to keep learning. Since I just switched them to flower should I give some of the 4-3-3 nutes or the 2-4-4?

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The higher nitrogen a couple of times. Leave both switches on.

Cwmoore577 said:

Ok, thanks I’ve definitely got to keep learning. Since I just switched them to flower should I give some of the 4-3-3 nutes or the 2-4-4?

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Stick with veg nutes for the first 7-10 days of 12/12 then switch to bloom.

hotrodharley said:

The higher nitrogen a couple of times. Leave both switches on.

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Renfro said:

Stick with veg nutes for the first 7-10 days of 12/12 then switch to bloom.

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Will do. Thanks for the continuous knowledge you guys have been a great help!

@Renfro @hotrodharley
Hey guys instead of making another post I thought I’d just tag you guys back on here.
So once I noticed yellowing I gave her a gallon of the Biothrive Grow (4-3-3) on August 27 at about 1 tsp/gal which is a half of the recommended light feed dose. Then another half gallon of it, same strength, on August 31st.
It’s now 13 days into flowering and still getting more yellowing.


Should I give another dose of the Bio Grow 13 days into flowering? Am I making it too diluted or just not giving enough?

Sorry to bother again!

Try feeding more often and stronger.

Renfro said:

Try feeding more often and stronger.

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Ok is there a certain point into flowering that I shouldn’t give the 4-3-3 mix or doesn’t matter and if there’s yellowing she needs the nitrogen?

If the plant wasn't nitrogen deficient then I would say switch feed to a flowering feed around day 20 of 12/12.

Renfro said:

If the plant wasn't nitrogen deficient then I would say switch feed to a flowering feed around day 20 of 12/12.

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Noted. Thank you! Canopy still looks great and buds are forming just hoping I can stop it spreading.

Cwmoore577 said:

Noted. Thank you! Canopy still looks great and buds are forming just hoping I can stop it spreading.
View attachment 4389148

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Yeah, probably too late to use Forbid then. Not sure the residual would be gone at harvest.

Cwmoore577 said:

Ok is there a certain point into flowering that I shouldn’t give the 4-3-3 mix or doesn’t matter and if there’s yellowing she needs the nitrogen?

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She’s had enough nitrogen for now judging by leaf shape.

hotrodharley said:

She’s had enough nitrogen for now judging by leaf shape.

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Renfro said:

Yeah, probably too late to use Forbid then. Not sure the residual would be gone at harvest.

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Shit I already gave it some.

Cwmoore577 said:

Shit I already gave it some.

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Don’t worry about it. It’ll use it.