Has anyone brought a plant out of this before? Should I give up?

[UndergroundFarmer]

This is mite damage! Hemp russet mites in all likelihood. Before you go too crazy flushing your soil or making radical changes in your tents, Google images of mite damage and see if anything looks similar to what you're dealing with. Severely infested plants should be trashed, possibly burned even. I let most of them freeze to death outside. The rest will be washed off with Lost Coast Plant Therapy unless I need something stronger. I don't think grow sites emphasize integrated pest control enough. This is not a problem most growers will know how to handle until it takes down enough of their plants. 1/31/2022

I've had another batch in veg turn up this way. The new growth crinkles up and growth nearly stops. I let the humidity levels fall too low. I have an Alien Rock Candy that isn't affected because it was transplanted later than the rest after I figured out that the low RH was screwing everything up. All else was the same.

Here's a sample:



I've got two new Niwas keeping things in line now. I thought for a while it was brought on by stress from manifolding them so I laid off cutting on the ARC until this week after I was satisfied that she was healthy enough. Still, I only gave her a simple topping. New growth looks fine on her. I forget which one this one in the photo is, but it's probably Expert Gorilla (not that it matters). I've got another batch in the nursery so it's not such a disaster if they can't be saved, just a shame that I had to learn this way. It's just another one of those things that I never had to deal with in hydro.

 

[Rwise]

Also give them a good look over for bugs, bugs often cause leaf curl.

 

[Eliot Pryor]

That's what I thought also.

 

[Going2fast]

Check out this thread. I lost 4 plants this summer due to this. I thought high heat and humidity had caused it but it was only these four that were close proximity to each other. The. New growth looked exactly like yours. No signs of bugs on plant or roots. They all died within a few weeks
https://forum.growweedeasy.com/foru...answer-to-the-wilting-problem-some-are-having

 

[Gingerbeard]

When you say this happened to another batch, UndergroundFarmer , are you talking another grow or this?

 

[UndergroundFarmer]

I'm talking about another batch of seedlings moved to veg then manifolded. The survivors from the previous batch are in flower and they are trying but buds are tiny and very slow to develop.

 

[UndergroundFarmer]

I'm sure it isn't pH or nutrient issues. The Alien Rock Candy was raised exactly the same as all these others except that I throttled down the exhaust fan to preserve humidity levels after I realized that they had fallen into the 30s. She is growing like a champ. The rest are growing feebly with almost no internode space. I'll have to search for it again but I did come across a GWE article about low RH stress causing symptoms resembling Boron deficiency. The article didn't mention whether or not there was any way to fix them after this happens.

 

[UndergroundFarmer]

I've got a population of fungus gnats but they are mostly harmless and I'm about to run them off with Neem seed meal this weekend.

 

[UndergroundFarmer]

It took a few tries to get the page to load but I got it. I tried a Google image search and the infected plants don't resemble mine, in fact they look better! I might just make up a bleach solution for the trimmers though to be safe. I might just start pinching to top and defoliate more as well so I can get around the danger of infected trim scissors.

 

[Gingerbeard]

Quick Wikipedia link. Cannabis mention.

 

[UndergroundFarmer]

Here's the GWE page about Boron deficiency which I believe caused my issue.

"Boron is not absorbed well if there isn’t enough moisture, for example if plant is underwatered or humidity is very low (below 25% relative humidity in the air). Proper watering practices will help prevent underwatering, and a humidifier may be needed to achieve the best growth if your grow room is very dry. Boron is not absorbed well if there isn’t enough moisture, for example if plant is underwatered or humidity is very low (below 25% relative humidity in the air). Proper watering practices will help prevent underwatering, and a humidifier may be needed to achieve the best growth if your grow room is very dry."

The first time around, I went crazy blaming the nutrients, the pH adjusters and probably made the whole situation worse. I'll get more pictures of the damaged bits this weekend and a shot of the Alien Rock Candy that wasn't exposed to low RH. This trouble only started this winter so it all makes sense.

 

[Gingerbeard]

I won't post any of the sites I looked at. GWE has similar information.

When the late Sexless M was growing, I made a post about hollow stems. Boron deficiency comes up a number of times in research. Might I ask you to pinch a stem? Maybe that'll give you a little more evidence, boron or not?

 

[UndergroundFarmer]

I tried a few. The smaller stems are solid enough. The main stems I topped were hollow.

 

[UndergroundFarmer]

Northern Lights:

Alien Rock Candy with NL just behind it:

They are both in the same mix with pH hanging around in the 6.2-6.8 range.

 

[UndergroundFarmer]

That's a 9 finger leaf up top. She feels good!

 

[Gingerbeard]

Evidence for B-def?

 

[MagicMike66]

I had 2 autos that did this on my last grow, one after the other. No idea what caused it but I just tossed both of them

 

[SoOrbudgal]

You sure you don't have heat or circulation issue? They look like their dehydrated ?

 

[UndergroundFarmer]

B-def apparently triggers some degree of calcium deficiency too, so yeah, kinda.

 

[UndergroundFarmer]

They've been both a little cold and a lot dry before I took care of the environmental challenges.