Removing yellow leaves

I'm growing 5 plants in a greenroom 4x4 tent. plants are white widow clones in coco medium in 15lt autopots under a 600w lamp. air exchange is very good temps always between 24-28 humidity also good.I'm using canna nuts and sticking religously to the canna grow guide nuts schedule. I'm 2 weeks into flower and in the last week all my leaves have started to turned yellow with very purple stems & veins. this is not my first grow but my first for a number of years and my first in a tent. I'm in a soft water area and I'm very meticulous on my PH levels which is always 6.4 in my nuts res. up until the last week or so my girls looked in perfect shape & healthy but as each day has gone by this week they just seem to be getting worse. I have stopped all nuts and they have been on just water for the last 3 days PH 6.4.From reading previous threads on here it seems to be a common problem and there seems to be so many differing opinions. so after a lot of differing advice i have upped the nitrogen and magnesium in the last couple of days. I'm now monitoring how the plants react to this.


I understand the yellow leaves will not recover and a lot are now going brown and crispy (dieing). plants are now back on Canna A+B, Canna boost , canna nitro, and a teaspoon of epsom salts. the bud development is coming on well and they are drink there nutes like they are starving and I've lowered my PH to 5.8. My question is should i remove all the unhealthy leaves or just leave them to brown up go crispy and fall off.

I'm pretty sure the clones where auto flower white widow as they began flowering on 18/6 light cycle, which was a surprise to me as I have never come across auto-flower before.
SO SHOULD I STRIP HER OR NOT ?????

Remove all dead and necrotic leaves.

Sometimes if the leaves are yellow, but, not necrotic, and they're still nice and formed, I'll leave them on, I think they still provide solar energy, as long as they're not blocking anything below.

it's ok to pull of the ones that are already being cut off by the plant, any others I'd not touch.

got a picture of the plants / pots? could be root bound or salt build up.

BenFranklin said:

Sometimes if the leaves are yellow, but, not necrotic, and they're still nice and formed, I'll leave them on, I think they still provide solar energy, as long as they're not blocking anything below.

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Yellow leaves do not photosynthesize anymore and contribute nothing to the plant as the yellow tells you that the plant has removed any available N and used it.

Right... it's not photosynthesizing...

But it may still be used as a solar panel for other parts of the plant. or the plant in general.

Like I have a plant right now, most of it's leaves are yellow, it's two foot tall.

The leaves have been yellow for about 3 weeks now, but, they are not becoming necrotic. The plant is still producing.

Sounds like you burnt them with the boost, dont use boost in future its too risky just use terra vega and terra flores, both designed for use in coco. i use it and have most leaves still green at the finish which gives you a lot more weight.

A large cola with green leaves at harvest is almost always heavier than a yellow/brown leaf cola.

Imaulle said:

it's ok to pull of the ones that are already being cut off by the plant, any others I'd not touch.

got a picture of the plants / pots? could be root bound or salt build up.

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the pot are 15ltrs which i have used successfully in the past.

they seem to be coming round a little

Looking very nice actually for 2 weeks in them buds are gonna be huge! provided nothng goes wrong til harvest. Buds on my current grow are similar size but I'm 6 weeks in lol. I guess this is difference between 600W and 250W grow...

Hmm interesting, I was led to believe that auto plants are generally not/cannot be cloned.

just curious, is there any P and K in the feed?

Personally i leave yellowed/dead leaves until they drop off by themselves or come off with a very gentle tug.

Grow4myfriends said:

Looking very nice actually for 2 weeks in them buds are gonna be huge! provided nothng goes wrong til harvest. Buds on my current grow are similar size but I'm 6 weeks in lol. I guess this is difference between 600W and 250W grow...

Hmm interesting, I was led to believe that auto plants are generally not/cannot be cloned.

just curious, is there any P and K in the feed?

Personally i leave yellowed/dead leaves until they drop off by themselves or come off with a very gentle tug.

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yeah I have found out autos cant be cloned but these definatly started to flower before I turned them on to 12/12. strange !!!

I'm just now going into my 4th week of flower and just added PK 4/10

I took off a lot of very yellow leaves and with the changes I've made they seem to be back in rube health and doing well.