Yellowing fan leaves

[Skit Rat]

I have found I have yellowing fan leaves on the underside , why is this ?

 

I removed them , the plant is at the start of flowering .

[handysmoker]

Because the plant don't want them any more if it's now flowering, don't cut too many of .... But you need to post a pic to confirm if this is the case.

 

Someone else will have to tell you why

[Cajafiesta]

Assuming your environment and watering practices are in check, it's likely down to the plant being hungry.  It is likely NOT because " the plant don't want them."

 

These plants don't generally make conscious decisions to eliminate foliage that is the key to photosynthesis...which is the key to the plant's life.

 

 

Post details and photos.  It will be easier for folks to help if you outline the following

 

Are you growing indoors or outdoors?  I assume outdoors because of the section you're in...?

Grow Media

Feeding schedule and nutrients used

photos of sick plants

volume of pots used if growing in pots

watering quantity and frequency

tent temps and humidity at lights on and lights off, if growing outdoors.

Average Day/night temps and humidity if you're growing outdoors.

 

 

If you're growing outdoors, about the best my pea brain can suggest without details is " feed them."

 

It's pretty common for the outdoor plants I'm around to develop yellowing fan leaves at the bottom.  It's the plant pulling mobile nutrients (NPK) from the lower leaves to support the new top growth.  But We've got real shitty, sandy soil here.  We have to feed them consistently.

 

Edited August 28, 2023 by Cajafiesta

[Military Grade]

If everything is on point no leaves should yellow for the whole grow (apart from last week Plain water)

 

I did this once and was very proud of myself, but only ever manged it once so far

[handysmoker]

Sorry .... got it wrong.  Stoned dumb ass sitting here.

[Shumroom]

What I’ve experienced recently,
In the first couple of weeks during blooming under LEDs,

I am constantly picking up leaves which have become disconnected from their branch/junction.

 

Bearing in mind that I don’t remove anything at the time I change my lights to 12/12,

I wait for 3 weeks before deliberately defoliating and removing stems that haven’t reached the canopy.

 

The leaves which have yellowed and fallen off haven’t been getting much light due to being shaded out,

so I’d agree with the statement above,

that the plants have decided that they should just drain them of mobile nutrients then let them drop 

 

 

I never used to get this under HPS and CMH  

 

Atb

 

 

 

[Shumroom]

About 35W per sq feet iirc.
 

I did try upping the power to my centre light(Par+ 275) this time around,

as it has more reds than the 2x Highlight 220 boards that sit on either side which are more on the blue side of things with their faux UV.

 

 

I did recently get a UT383bt and took some readings with it paired to the PPFD app on my phone just to confirm my thoughts on how much usable light withered was at different heights,

so I did turn the lights back down slightly as the plants stretched.

 

I’m going to check to see if the hygrometer needs a new battery,

I think it might not have been changed in quite a while.

 

Do you think I’m being too cautious with light levels or EC?

 

They were running at EC 1.5 and I increased to 1.6 a couple of days ago,

i was thinking about going to EC 1.8 just to see what reaction I get 

 

Atb

 

 

 

[UKsFinest]

I'm in the same boat I get lower leaves dying off i was only feeding 2ml shogun bloom but upped it to 3ml I'll see how they go on that.

[DutchFox]

8 hours ago, Skit Rat said:

I have found I have yellowing fan leaves on the underside , why is this ?

 

I removed them , the plant is at the start of flowering .

 

your guerilla plant was withdawing nutes from the leaves....and then you removed them.....so the plant will look for more nutes from other leaves...

i never do this removing in gg.....and it makes unnessesary wounds too.

 

in good ground/nutes they stay green till the end.

Edited August 28, 2023 by DutchFox

[Shumroom]

Apologies @Skit Rat I didn’t spot that this was in the outdoor section  

 

@Fatboy77 I look forward to running a tent full of clones again,

but I’ve got lots of seeds I want to get through too.

 

Tbh because the leaves were so low down on the plants I’ve never considered this to be a problem,

like I say I’ll experiment a bit more with feed strength and spectrum 

 

Atb

 

 

 

[DutchFox]

7 hours ago, Shumroom said:

 

Tbh because the leaves were so low down on the plants I’ve never considered this to be a problem,

 

 

yes i agree...a few weeks in bloom...i call the beginning yellowing at down the plant...... "" nice autunm coulor ""   

 

with wind they fall off after the plant is done with them ....