Help leaf problems and stunted growth

[Leatus]

Hello I’m new to growing. I’m having a problem with stunted growth and leaf spots and yellowing. I’m growing 6 white widow in a 3x6 tent indoor. The tent temperature is 28c. My water with nutrients added is ph 6 any help would be appreciated.

 

[Choppr]

Confirmed your leaves are spotting, and show mild chlorosis.....? pH is OK, Im a coco/hydro grower Im usually target 5.7-5.9
no info - pretty hard for anyone to help -

what's is the media? it looks like pure coco?
what's the feed program? what have you added so far? how much? nutrient brand/type? watering practice?
what kind of lighting, power setting? light height?
what do the other 5 Plants look like?

Im guessing coco so I'll take a stab....

That pot looks dry! Coco needs to stay wet with about 50-60% dry-back, to pull necessary Oxygen back into the Rhizo - never let it go below 30% wet (60%dry). Coco is a continuous feed system - Fertigate to 20% runoff as pots become 60% dry. (everyday/every other day).

*Letting coco go dry will concentrate nutrients in the "Perch", and can become toxic. (see "perched water table" coco)

 

[Leatus]

it’s 100% coco you are right. I’m using canna co co A&B, rhizoctonia and cannazime all at half strength. They look dry because I seen a few gnats flying about so a let them dry. Probably water them every 3 days. The lights are set at 400w now. Can turn them up or down.

 

[yamyam222]

Don't let pure coco dry out too much. Your PPM and EC will sky rocket in the medium as the percentage of moister decreases. Think of it like a sponge in your sink, after you do the dishes and let the sponge dry out it becomes encrusted in crap. Coco requires frequent buffering aka watering until runoff to establish a balanced nutrition ratio throughout the medium. If you let it dry too much and too frequently you'll roast the roots and the plant.

 

[yamyam222]

I would flush the pots with 1-3 gallons of your current week feed and calmag. Too much water won't matter. It'll run off while cleansing the medium. The remaining liquid will buffer your coco sponge at that exact PPM.

Also, since your root ball is not formed in that large pot, you will have to consider accelerating the dry back with a fan to ensure the next watering can progress before the medium becomes stagnant without oxygen (about 24 hours).

Finally if you don't have a fabric pot. Consider getting one. Tending to coco without good air flow around the root ball is asking for trouble.

 

[Florida_Mike]

Don't forget that coco will become hydrophobic (repels water) if allowed to dry out. From the web:

Why Coco Coir Becomes Hydrophobic:​

• Surface Tension:
  When coco coir dries completely, it loses its moisture-absorbing capabilities temporarily because the fibers shrink and compact. As it dries, the surface tension of water makes it difficult for new water to penetrate, causing it to run off instead of soaking in immediately.
• Salt and Nutrient Build-up:
  When coco dries out, nutrient salts left behind can accumulate, further reducing its ability to absorb water.

What Happens if Coco Becomes Hydrophobic:​

• Water Runs Off:
  You'll notice water pooling or running off rather than soaking into the substrate.
• Uneven Moisture:
  Roots may experience uneven moisture levels, leading to inconsistent growth, stress, and potentially nutrient issues.
• Plant Stress:
  Plants can suffer from root zone stress, impaired nutrient uptake, or nutrient burn due to increased salt concentration.

How to Fix Hydrophobic Coco:​

• Slowly Rehydrate:
  Water gradually, using small, slow applications of lukewarm water, allowing it to soak in gently.
• Wetters or Surfactants:
  Use mild wetting agents (such as Yucca extracts or a few drops of biodegradable soap per gallon of water) to help water penetrate quickly.
• Consistent Watering Practices:
  Avoid letting coco coir dry out entirely. Maintain regular irrigation to keep coco evenly moist but not waterlogged.

 

[Leatus]

Thankyou il give it a shot. Il report back in a week.

 

[Gmix]

Get some nematodes to deal with the gnats.

Finally if you don't have a fabric pot. Consider getting one.

Folks have growing in coir for years before fabric pots where even a thing with success.

 

[yamyam222]

Get some nematodes to deal with the gnats.


Folks have growing in coir for years before fabric pots where even a thing with success.

Agreed. But this kind of condescension is not a reason to not use one.

 

[Gmix]

Agreed. But this kind of condescension is not a reason to not use one.

lol really big words you may as well just said fuck off

 

[eLBowAutoGrows]

You’re on the right track. Curious on why you decided to go half strength?? Also I would keep in mind all those leaves are going to be pruned off before you know it. So as long as the new growth is healthy and frequent. You still have time to dial stuff in and make changes suggested. Also if your into coco you should look into bottom feeding.

 

[Leatus]

I would flush the pots with 1-3 gallons of your current week feed and calmag. Too much water won't matter. It'll run off while cleansing the medium. The remaining liquid will buffer your coco sponge at that exact PPM.

Also, since your root ball is not formed in that large pot, you will have to consider accelerating the dry back with a fan to ensure the next watering can progress before the medium becomes stagnant without oxygen (about 24 hours).

Finally if you don't have a fabric pot. Consider getting one. Tending to coco without good air flow around the root ball is asking for trouble.

When you say 1-3 gallon do you mean per pot? That’s like 8 to 12 litres of water

 

[Leatus]

You’re on the right track. Curious on why you decided to go half strength?? Also I would keep in mind all those leaves are going to be pruned off before you know it. So as long as the new growth is healthy and frequent. You still have time to dial stuff in and make changes suggested. Also if your into coco you should look into bottom feeding.

I went with half strength because I thought the spotting was from over nuting or to much of something

 

[eLBowAutoGrows]

Roger that, good thinking. What most people call “too much food” (Ec level) can also be linked to an off balanced PH. (How well plants can metabolize the food) which is also linked to how much light they are getting. To help narrow this down in the future keep a log book of
EC
PH
PPFD
DLI
VPD
Hope this helps! Happy growing

 

[Leatus]

Roger that, good thinking. What most people call “too much food” (Ec level) can also be linked to an off balanced PH. (How well plants can metabolize the food) which is also linked to how much light they are getting. To help narrow this down in the future keep a log book of
EC
PH
PPFD
DLI
VPD
Hope this helps! Happy growing

I have got to honest mate I literally don’t have a clue what all them things are. It sounds way more complicated than I thought it was guna be. I knew I was guna have to put some effort in but didn’t think I needed a degree in botany

 

[eLBowAutoGrows]

I have got to honest mate I literally don’t have a clue what all them things are. It sounds way more complicated than I thought it was guna be. I knew I was guna have to put some effort in but didn’t think I needed a degree in botany

All good brotha. It can be simplified pretty easily with a little research and a couple fairly inexpensive tools.

 

[firstgrowdontknow]

I have got to honest mate I literally don’t have a clue what all them things are. It sounds way more complicated than I thought it was guna be. I knew I was guna have to put some effort in but didn’t think I needed a degree in botany

Buy a ph and a tds pen. You probably wont be successful without them.

VPD(vapor pressure deficit) can safely be ignored as long as your temps are in range.***

PPFD/DLI are fancy ways of measuing how intense your light is, you can do this by feel/how the plant looks.

*** humidity is often a luxury here, vpd isnt useless, but for a new grower there are bigger blunts to smoke.

Do a little youtube/reading on EC and PH, those are the only hard numbers you NEED. Oh, and a thermometer too to keep an eye on the tent temperature.