Persistent Growing Problems

[CreatioExnihilo]

Hi, I am writing this on behalf of a friend who has been having some troubles consistently with each of his grows.

Everything starts out fine but by week 5/6 onwards the plants always start to die off, leaves and buds drying and browning from the bottom up. Various strains have been tried but the results are always the same. Tried fumigation and sulphur room treatments but nothing seems to make a difference.

Last attempt has been to clean out the whole room and do a singe plant in the space but with similar results. Some photos included.

Additional data: coco crow, sealed room + co2. London water. Canna nutrients. nothing fancy. Temperature and humidity maintained (see data). Normally hand watered but this one was on a dripper for a few minutes once a day.

i am just posting this in the hope of fresh insight.....

 

[PurplePotion]

My guess is root issues. That looks like quite a bit of coco for such a little plant. Perhaps root system is not strong enough/large enough for such a pot and is being overwatered.

 

[RockinRobot]

Not nearly enough info. What nutrient strength? What Ph?
What ppm CO2?

CO2 can cause all kinds of issues if improper feeding occurs.

 

[Douglas.Curtis]

Jim Weed. Nothing personal, I've just seen this quite a bit over the years. It's ok, you can fix it the next run.

Jim weed is a term I coined about 10 years ago. It means cannabis which has been seriously overfed, so much so it interferes with reaching maturation. Commonly created by following Mfg recommended feeding charts, especially in less than optimal growing conditions.

Use lower strength mixes, drop the strength when physical flower bulking quits. At week 4-5, the flowers on many hybrids have quit physically growing. Their nutrient needs drop significantly, so overfeeding starts having a muuuch larger impact on plant health. Cannabis is great at phytoremediation. Plants which are good at phytoremediation look 'ok' while they're packing on quality killing excess nutrients. They do have their limits though.

 

[CreatioExnihilo]

Thats interesting. I havent heard of that scenario before.



CO2 ppm is kept at 900ppm.



Water in the area starts around EC 0.8 on a good day which makes things a bit more difficult but afaik feeding charts have been observed and maintained with a guardian monitor. He has been doing this for a while so has a few bits of good kit. I have run the same strains with similar feeding regime without the problems. Even happens (though maybe not as badly) with usually much more bulletproof strains like Ami and Silver Haze.



I realise the next steps are filtering the water. Just want to rule out pathogens/fungus/other before suggesting doing anything else.

 

[CreatioExnihilo]

pH kept 5.8-6

 

[Douglas.Curtis]

Water in the area starts around EC 0.8 on a good day which makes things a bit more difficult but afaik feeding charts have been observed and maintained with a guardian monitor. He has been doing this for a while so has a few bits of good kit. I have run the same strains with similar feeding regime without the problems.

Ok, so you've run the same strains with similar feeding without the problems. The photos show plants which are seriously overfed, so something is different between you two. Jim described almost the same exact issue, except his story was from the other side of the fence. "My buddy runs all of these strains, these nutes, this feed schedule and he does fine. I do the same thing and my plants look like this..."

Jim's setup did not create the same conditions as the grow he was trying to copy. There's no way his plants could use the same feed levels, so his plants ended up looking very much like yours. Smaller flower development, dark leaves, smaller plants, and at week 4-5 they'd start burning from the bottom up. I'm pretty sure you're experiencing the same thing.


Please list all of the differences you can possibly think of between your grow and their grow.

Light type, wattage, watts per square foot
Hood type and distance of lights to plants
Temps
Humidity
Air Exchange Rate
Media
Root zone temps
Water source (Which can be *very* different even 5 miles away)
Nutrients
pH up/down (there are many different formulas)