help with deficiency

[zirk]

Hi everyone

its my first grow. 5 auto flower plants under 400w hps. the 3 plants on the back are 6 weeks old, and the 2 on the front are 5 weeks.

seeds were planted straight into 3 gallon pots with biobizz allmix.
im using bio grow bloom top max bioheaven and molasses

I water every 3 days (RO water) and water with nutes every other watering.
last feed they got was 6ml grow 4ml bloom and top max with 2 teaspoons of molasses per gallon (little less for the smaller girls). the thing is i believe i started giving the nutes too late and in too small doses

temp is stable on 72-78 f
i checked the run off ph and it was 6.9
so i guess ph is fine.

they started yellowing from the older lower fan leafs
but now the whole plant looks pale.

how can i fix this?
should i keep using the bio grow?.. cause i was supposed to stop using it by now..

 

[Reiss]

It's quite normal for the fan leaves to yellow as the plant reaches maturity but I agree, it does look a little deficient in something.
My last auto grow (link in my sig) looked a little like your towards the end but ending up being a great yielder and fantastic smoke.

I wouldn't worry too much as they only have a few weeks to go. Here's a BioBizz feeding schedule I found on their website:

 

[eza82]

IMO....PH is high, we keep it the range of 5.5 - 5.9... no higher than 6. But thats in coco.
Looks like you have a PH lock out !


here is a table that will help ;

 

[Go Go Ganja!]

what is the npk of your ferts? u should really wait till the last 2-3 weeks to use molasses ...but im not sure how far along you are... and also its pretty normal for fan leaves to turn yellow during flowering.. the plants are focusing on the buds now not the leaves. good luck they still look great if u ask me!

 

[Go Go Ganja!]

5.5 is too low for soil you want it closer to 6.5 idealy.....6.2-6.9

 

[eza82]

My fans or any leaf will only turn during flush ( last two weeks) .
I think Magnesium. But for sure a deficiency. And IMO, PH related.

Outdoors we run 6 - 6.1.

Sorry should of read more carefully. Still think PH related.

What is your water staring at ?

 

[Reiss]

Adding a little epsom salts will help any Magnesium deficiency.
You should be aiming for a PH of 6.5 for a soil grow.

 

[cowboylogic]

Looks like they are hungry for some N. Most bloom nutes do not contain enough nitrogen. But with only a couple of weeks to go I wouldnt worry about it much. Not much time left to correct any issue anyways.

 

[eza82]

if you have only 8 wk flower, for sure dont stress.

 

[zirk]

whow you guys are fast...thanks for all the greats comments

i feel so relieved...

i was feeding with ph of 6.6-6.8
ill try correcting the ph next feed with 6.0-6.3 ?
i started using molasses just now ...they only got it once...

hey reiss just saw your ak grow and its too awesome.... really is a grow for me to look up to
do you find the biobizz schedule accurate for mj?
and if so how do you apply it on auto flower?

cause i think i got it all wrong

thanks again for all the help

 

[the420 apprentice]

it looks to me like the stems are turning purple and that means nitrogen but its to late to correct it just try to minimize the damage. i just finished some auto snow and had similar issues but i burnt mine. but still smoked fing great. others keep telling u that its ph but its not u have no leat curl up or down. im sure more nitrogen next time and u will be ok.

 

[Reiss]

hey reiss just saw your ak grow and its too awesome.... really is a grow for me to look up to
do you find the biobizz schedule accurate for mj?
and if so how do you apply it on auto flower?

cause i think i got it all wrong

thanks again for all the help

I think your PH is fine as it is.
I pretty much followed the chart for my autos, feeding from about week 3, a little bio-veg, a little more bio-bloom and a drop of topmax every water. Added 2 teaspoons of molasses every week.
I still had a little yellowing towards the end though. Finished off by flushing with water & a teaspoon of molasses for the last week.

 

[cowboylogic]

whow you guys are fast...thanks for all the greats comments

i feel so relieved...

i was feeding with ph of 6.6-6.8
ill try correcting the ph next feed with 6.0-6.3 ?
i started using molasses just now ...they only got it once...

hey reiss just saw your ak grow and its too awesome.... really is a grow for me to look up to
do you find the biobizz schedule accurate for mj?
and if so how do you apply it on auto flower?

cause i think i got it all wrong

thanks again for all the help

I just noticed you use r/o water. In future grows I would either add molasses or cal-mag to your feeding program, start to finish.