Plants yellowing...plz help :/

[CyberBuddha]

High

 

I'm a fairly seasoned grower of about 8yrs. But in the last 12months I've made some changes in the way that i grow and it has caused a problem - yellowing plants, usually in the flowering period.

 

Now this isn't your normal mild yellowing that's natural. This begins from the bottom inner leafs and spreads to the top over time. After many montths trying different things, this is the conclusion I've come to: The roots are starved of oxygen.

 

I used to grow 4 medium sized plants in 95litre pots. I would use one 95ltr pot inside another one. I'd use a pot sock and  have hydrotonne at the bottom of it. Followed by a mix of coco and silica rock. Never had a problem.

 

Fast forward 5yrs after taking a decent break. I now grow 2 plants at a time but they're 3times as big.  Instead of using two pots where one is inside another, they've since come out with those little stands you can put in the base of the pot. I use them. I didn't use hydrotonne and I used straight coco. I see my mistake there now. I'm wondering if growing the plants huge crouds the pots up with root mass and they need extra oxygen down there. I'm hoping that if I go back to using two pots, that  the small space between the pots going down the sides of the pots to the base - provides oxygen to the base roots. Using a 95lt pot with a stand in the bottom pretty much has zero air in the bottom.

 

I have 2 very large plants that are 3wks into flower and are yellowing. What can i do? They're in the 95ltr pot with straight coco and no hydrotonne. Stupid i know, but what can be done now? Oxyplus?

 

I also have 2 more plants elsewhere that are 3wks into veg. They're each in thier own single 95lt pot, in a premixed coco/perlite/silica rock mix with hydrotonne at the bottom of the pot sock. The pot sock is sitting on one of those stands inside the pot. Do you think that those plants will have the same problem when I grow them huge too? I was thinking of perhaps getting a mate over to help lift them out by the pot sox and putting them in the double pot set up that seems to have worked in the past.

 

If anyone has any experience or has a link of how to put air stones into pots I'd love to hear about that also.

 

All advice appreciated.

 

Thanks.

 

PS, I should mention that everything else is fine. PH, EC, temperature etc is all normal as per what I've done for many years.

Edited February 23, 2014 by CyberBuddha

[Carlos Danger Mouse]

Pics tell the story

[Leeroyrips]

Well im not so sure bud 95Lt is alot of room for roots and O2 without pics its hard to say. I think your right in looking down not up to solve the problem

 

Hazard a guess Root Rot or Botris, Pthoff,

Seeing how you said you tried nutes to fix the problem its not just N def so yeah Pic plz bud

Not sure if i read right but (multiple plants) in pots is just common sense 1 Pot Plant 1 POT Happy to be corrected.

And if that's the case give them MORE O2 enriched water at feed time.

Whats your EC for this set-up does 2 plants 1 pot mean 2x the nutes i highly doubt it would.

[thc24]

Quick thing you could try. Sounds like the plants are big for indoor and larger than ur last 95litre root space is more than enough. First put a thermometer in the soil avg root temps if hot then may be a oxygen starvation prob in a big pot unlikely. My bet is the roots haven't filled the pot so the soil is overly damp all the time which starves oxygen messing note uptake allow pots to feel light between waterings. And up the nute strength to start reversing the leached of food plants which will reset to good ec and pH in the coco. Best way to get air into the soil n plant would be to well air ate note solution in Res betweendaily feeds.

 

Let us know how they bounce . Back to good health and booming growth I hope. Is worst time to have issues. Gl