Everytime I hit around week 5 my plants start to die at a alarming rate

Odin*

Well-Known Member
Room temp is right around 78 82 under lights dark time I'm about 70

It is the difficulty in definitively answering that keeps me out of these types of threads. Here are the scenarios I am seeing based off of what you have shared;

1. Water evaporates faster at higher temps and if you are running an AC and/or a dehumidifier you could be "artificially" drying out your medium. By that, I mean that your plants may not be drawing in the water/nutrients and releasing that water via transportation due to insufficient root growth/health and insufficient photosynthetic "area" (insufficient for the volume of water introduced on a daily basis), and it is your "environment" that is drying the soil. In this event, some/most of the nutrients are left in the soil (the plant is not taking them in and using them), which causes imbalances/burn/lockout, despite the fact that you are only "feeding" 1/7.

2. The plant is releasing all of/most of the water via transporation and is not leaving much/any of the nutrients behind. This would mean that they are suffering from deficiencies/imbalances.

3. Root/plant material is sufficient, but heat is causing an accelerated rate of transporation, forcing the plant to drink more, so water uptake is adequate, but nutrient levels for that volume are relatively high. So, water volume good, but because of excess "sweating"/uptake, nutrients exceed plants needs, resulting in burn/lockout/imbalances.


If anything, it sounds like you've got some work to do in getting the environment/grow "dialed". Get your temps down, first step.

Edit: phone autocorrected "suffering" to "slaughtering".
 

Kingrow1

Well-Known Member
My humidity is consistent around 50% is that to high, and the heavy 16 is to expensive for me to keep having problems, I've been thinking about switching to all Fox farm I heard it's a little more forgiving.
Dont place humidity meter under the lights, with good ventilation it shouldnt be far off the room the tent is in. Powdery mildew at 50% humidity dosent sound right...
 
Dont place humidity meter under the lights, with good ventilation it shouldnt be far off the room the tent is in. Powdery mildew at 50% humidity dosent sound right...
I'll double check humidity again in the am, but I'm pretty sure it's right around 50%
 

Odin*

Well-Known Member
I'll double check humidity again in the am, but I'm pretty sure it's right around 50%
I believe that your temps are higher than you think (no AC). That 50% (relative) humidity at high heat means that the Absolute Humidity is much higher.

Even then, low temp, low humidity, your ailing plants are much more susceptible to it. Again, THE CONIDIA OF POWDERY WHITE MILDEW ARE UNIQUE IN THAT THEY DO NOT NEED HIGH HUMIDITY TO INFECT YOUR PLANT. That's not aimed at you @William420, but those that suggest low/high humidity governs powdery mildew. It absolutely does not. Low humidity can slow it's spread, but will not prevent it. Infection is health and strain dependent (some strains have higher/lower resistance.

Your higher Absolute Humidity will aid its spread. Cooling the room (via AC) will draw moisture (condensation) and the cooler temps will lower Absolute Humidity.
 
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theslipperbandit

Well-Known Member
6.5 u want but later in flowering it can go to 6.6-6.7 due to different requirements...your plants are definitely struggling maybe u should change nutes I myself feed each watering but at different amounts n ingredients n never had salt build up n I feed till crop then recycle the soil.
 

theslipperbandit

Well-Known Member
And a big up to canopy management and more circulation I've an intake fan connected to a suspended 9"ram via ducting yoyos n zip ties that'll sort airflow then another 9"above my cobs with ducting letting out the heats that's produced from the cobs and my scrubber fan connected to my fan speed controller and outtake with an sms so my shit don't pass 25 n noticed cob grows lead to quieter fans and I've a big old 16' in the corner ready for the upper canopy n extra circulation even if ur rooms over heated good air exchange can make things manageable
 
I have a 16 inch oscallating, 2 6 inch stationary fans a 6 inch intake and a 8 inch exhaust hooked to my carbon filter and ran through my hoods if u think heat is the problem should I dim my ballast down to 600
 
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