Yellowing/ Browing Leaves - Help Please!

[HonBadger]

Hi all,

 

 

Same old story... my first grow. I have 6 plants total m - 2 plants that are doing pretty well but still have minor imperfections, 2 plants are doing ok but are pale and as leaves mature they yellow/ brown and eventually shrivel up. The final two plants are very small and undeveloped and have very few healthy leaves. All polants have fresh growth at the stem, but even some of these leaves have yellow tips. (see photos attached)

 

Details as follows:

• Strain: Northern Lights (6 plants)
• Medium: Coco
• Nutrients: Coco A & B
• Lights: HPS 600W
• Lights approx 600mm from top of canopy/ leaves
• 6" fresh air supply
• 8" exaust
• Pots size: 27Lt
• Room Temp: 22-27 degrees
• pH of Nutrient Solution: 6.0
• EC of Nutrient Solution: 1.0
• Watering/ Feeding frequency: every couple of days once top inch of medium is dry
• Watering/ Feeding Volume: to 20% Runoff
• Runoff pH: 6.0
• Runoff EC: 1.9 (excess nutrients being left in soil?)

 

I think i may have overwatered these plants when i first transplanted to the 27Lt pots (probably 6 weeks ago) and im wandering if some of the plants may be stunted beyond repair? Any assistance or information would be greatly appreciated

 

 

[bakedcake]

I don’t believe any plant is beyond repair unless it is literally just a stick but again you may be surprised. In all honesty I can’t really help you too much as I don’t deal with EC or PH. However if it’s starting to brown and take the bottom leaves it may be hungry for N sometimes plants may do this to keep food getting to the top of the plant and can also feed off the dying leaf but not waste energy trying to keep it alive. How does the new growth look? Are they also still growing? My plants will sometimes be healthy but just spit the dummy on certain leaves. Again some others may have advice on here

[Brim]

Probably a bit of salt build up leading to lockout or toxicity

 

Your plants don't sit in the run off nute does it ?

 

I'd flush them make sure they aren't sitting in run off then give them a feed

 

If you're using any additives give them a miss for a week or two and just give them base nute

 

500 ppm or 1 EC is pretty lowish/normal and could even come up to 700ppm or 1.4 ec when they come back

 

Also try and water to a schedule instead of just putting your finger in it , every second day should be sweet ... That's will give it a day wet and a day dryish and that way it should stop nute build up

 

Some bleaching on leaves could also be from hot spots in your grow

 

Edit: had another look and it's not bleaching , but if you don't have a oscillating fan grab one

 

Anyways good luck

 

We all learnt from making mistakes and if this if your first grow then you'll have many more mistakes to make in the future

 

Hope some of this helps

Edited June 12, 2018 by Brim

[HonBadger]

I don’t believe any plant is beyond repair unless it is literally just a stick but again you may be surprised. In all honesty I can’t really help you too much as I don’t deal with EC or PH. However if it’s starting to brown and take the bottom leaves it may be hungry for N sometimes plants may do this to keep food getting to the top of the plant and can also feed off the dying leaf but not waste energy trying to keep it alive. How does the new growth look? Are they also still growing? My plants will sometimes be healthy but just spit the dummy on certain leaves. Again some others may have advice on here

 

Thanks a lot. the new growth looks pretty good, but has just started to get yellow leaf tips. The 4 plants that arent doing so well havent gained much in elevation, but got new shoots up the stem when i pruned the old dead leaves off.

[HonBadger]

Probably a bit of salt build up leading to lockout or toxicity

 

Your plants don't sit in the run off nute does it ?

 

I'd flush them make sure they aren't sitting in run off then give them a feed

 

If you're using any additives give them a miss for a week or two and just give them base nute

 

500 ppm or 1 EC is pretty lowish/normal and could even come up to 700ppm or 1.4 ec when they come back

 

Also try and water to a schedule instead of just putting your finger in it , every second day should be sweet ... That's will give it a day wet and a day dryish and that way it should stop nute build up

 

Some bleaching on leaves could also be from hot spots in your grow

 

Edit: had another look and it's not bleaching , but if you don't have a oscillating fan grab one

 

Anyways good luck

 

We all learnt from making mistakes and if this if your first grow then you'll have many more mistakes to make in the future

 

Hope some of this helps

Thanks Brim,

 

No, the plants sit in a pot above a secondary pot were the runoff gets collected. I am thinking you may be right with the nutrient and salt build up. I havent been using any additives other than Coca A & B. Can i flush with this solution or should i flush with just pH balanced water, with no nutrients in it? When you flush, how much run-off are you looking to get? Anyway im sure i can google those answers but i really appreciate the advice.

 

I will set up an oscilating fan. At the minute im just running the ventilation fan with a long plenum attached with holes that throw the air over the plants.

 

Thanks again.

[Brim]

Dr aragon's flushing method is pretty decent , he flushes with a low EC solution ... Think 0.3ec

 

I just flush with tap water then feed normal strength straight after

 

My way probably isn't the best way and I'd recommend dr's way

 

There was a thread before that we had a discussion about the different methods of flushing

 

Can't remember which thread but I'll have a look and let you know which one it was

[Brim]

Thread is ...

 

First grow seems like it's dying.... by xtro

[HonBadger]

Thanks a lot Brim, Champion

[micmac]

Someone above said nitrogen deficiency, this is true , but what has caused this is the ?

Your plants need food, start mixing your nutrients at a lower ph 5.8

Mix nutrients to 0.8 ec

You will need a lot

Starting running this through your pots monitor run off

Take a note of what it comes out at initially

Keep putting this through until u r sure your runoff is reading ph 5.8 what u putting in now

Your EC should come out at .8

Never let completely dry, coco works best when it's kept at a constant ph

When u water make sure u get 30% run off each time, monitor

Looks like they r starting to come good with he darker green in the middle

Go through this process n in a few weeks they'll be back to normal

 

 

Sent from my iPhone using OZ Stoners

[HonBadger]

Thanks Micmac,

 

I have been mixing my nutrients at around 5.8, and make sure the mix is at 5.8 - 6.0 before every feed.

 

My E.C. hovers around 0.9 - 1.0, so that sounds pretty consistent with what you are saying.

 

My EC on runoff is coming out double (1.9) so do you think they may need a good flush?