Droopy and thin leaves - RH issue?

[karlkutta]

What's going on guys! I was hoping I can sort this out but couldn't.


-Problem: leaves drooping and thin

-Medium/grow method: soil; foxfarm ocean forest but it's old soil, i.e. the original funky nutes have been cycled out

-Feed and supplements used: advanced nutrients sensi bloom mix A/B 10ml per gallon. Plus 4ml foxfarm calmag.

-Water source: tap water sits for usually 24-48hrs +

-Strain and age: affected are a fast buds green crack and Mephisto Fantasmo Express. Both are 39 days old I think.

-Climate: rh 45%. Temps generally 77f

- Light used: LEDs. Mehzi single cob, purple King led light, 3 spot bulbs with dome removed. Total wattage for lights is 300w at the wall. 20/4 schedule

-Additional info: been trying to increase RH. But it's cold and heater running is drying out all ambient air. Placed a bunch of trays with water and buckets with towels etc.

Sorry for the poor pictures

 

[Simplicio]

Higher humidity could help.
Wet towels, buckets of water, etc won't help much.
Get some top fill, ultrasonic humidifiers, and use RO water in them to avoid white dust.
Slowing the exhaust fan will also help to keep more transpired moisture inside the grow space.

 

[karlkutta]

How about more lights off, maybe intermittent lights off? 10/2 that seemed to raise rh

 

[Beerhunter CDN]

I don’t believe this is solely due to RH. It is a lower than ideal RH so increasing it would help your environment. How frequently are you watering? Are you watering to runoff? PH Perfect works when the nutes are in a bucket but not always perfect in soil. Nute buildup will change the pH in the soil. Have you checked the pH and concentration of your runoff?

It’s tough to tell from pics but the leaves look papery and twisted up a bit. Even though they are green, do they feel dry and paper-like?

The leaves also appear very dark green which is an indication of high nitrogen, the leaves could be clawing and dropping which means nitrogen toxicity. You may need to back off on your nutrient concentration. What concentration is your feed going in? Ie.). ppm or EC

 

[OrganicMids]

Rh will not cause these issues. Definitely looks like N toxicity

 

[karlkutta]

You guys might be onto something about N toxicity. Had been giving them a little more GROW to help her stretch more when I should have gone and fed bloom. I will try flushing the affected girls.

 

[Simplicio]

I don’t believe this is solely due to RH. It is a lower than ideal RH so increasing it would help your environment. How frequently are you watering? Are you watering to runoff? PH Perfect works when the nutes are in a bucket but not always perfect in soil. Nute buildup will change the pH in the soil. Have you checked the pH and concentration of your runoff?

It’s tough to tell from pics but the leaves look papery and twisted up a bit. Even though they are green, do they feel dry and paper-like?

The leaves also appear very dark green which is an indication of high nitrogen, the leaves could be clawing and dropping which means nitrogen toxicity. You may need to back off on your nutrient concentration. What concentration is your feed going in? Ie.). ppm or EC

Agree that problems are due to much more than humidity.
But higher humidity will help promote growth.

 

[karlkutta]

So cutting off my exhaust fan / extractor really pushed rh up fast because of all the water source I have in there. I did flush the affected plants and have them light feeding with bloom. Let's see what happens

 

[Beerhunter CDN]

So cutting off my exhaust fan / extractor really pushed rh up fast because of all the water source I have in there. I did flush the affected plants and have them light feeding with bloom. Let's see what happens

I found it difficult using Sensi Grow and Bloom with other AN products to stay away from nitrogen toxicity. If you can slow your extraction fan down or have it cycle on temperature or humidity, or both, it will help increase your humidity. If you can, add a small humidifier and you will get better results. I would not necessarily lengthen your dark time to increase humidity, there are other issues at hand to manage without introducing another variable.

 

[Arthur]

Fox farms is known to have issues holding pH.

You stated old soil... am betting your medium pH has crashed.

A slurry test would show if this is the issue quickly.