What do you think?

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

AluminumMonster

Duke of Errl:)
Joined
Mar 2, 2011
Messages
1,299
Reaction score
59
So we've been having an issue pop up lately at work... The plant loses it's leaves aggressively over 1-2 weeks and dies. I personally think we have been over watering, however, my boss thinks it is Rust. I would like some other opinions on this matter.

We are using Elevation Organics Soil and nutrient line along with their dry amendments: compost, earthworm castings, and dry root-zone inoculant.

We have been applying the dry amendments as a topdressing once per month.

The liquid nutrients are applied once every 2-3 watering's.

Teas made from the dry amendments are applied twice per month.

Well water with an average ppm of 300 is used every time.

PH always lands at 6.3.

These are in 20 gallon fabric pots.

These are in a 5000sqf greenhouse. We have 3 total.

Temps vary between 65F - 120F depending on outside temps.

Strain is Charlottes Web.

Approximately 2 weeks ago my boss added some expired molasses the reservoir in said greenhouse. The jugs were severely swollen.

View attachment 20170821_130308[1].jpg
 
well, that is freaky and horrible AM, I am just sitting scratching my head. Have you looked for bugs? Overwatering looks just like underwatering, they wilt. You look like you have burned? We will get some more folks in here. We need the Duck, for one.
I had one clone of CW and it was very puny and I culled it. It came with russett mites.
Good luck AM, that is horrible.. we need to figure it out...no duh, huh. I will ask duck to come take a look.
 
Is this just the one plant or are all of them being affected?

For one thing, I would expect that 120 degree temps would affect them adversely, even if it is for short periods.

Have you had your water analyzed to determine what the 300 ppm consists of? Large amounts of one element could be affecting others. My well water has arsenic and nitrates in it. I filter the water for my plants. https://www.amazon.com/gp/product/B01N8TYQ9W/?tag=skimlinks_replacement-20

I know in hydro if I have plants with leaves dying like that, it is often caused by root rot problems/res temps too high. You speak of a res in your greenhouse? What is that? I doubt that expired molasses would cause problems. Jugs swell because you have microbe activity going on in there, not necessarily because expired molasses is causing problems. Or did they go anaerobic? That could cause problems.

I'd also be for mulching the plants, especially since you have temps so high. It will slow the evaporation of the moisture.

I have never heard of rust as being a cannabis plant problem? What exactly is Rust?
 
Last edited by a moderator:
well, that is freaky and horrible AM, I am just sitting scratching my head. Have you looked for bugs? Overwatering looks just like underwatering, they wilt. You look like you have burned? We will get some more folks in here. We need the Duck, for one.
I had one clone of CW and it was very puny and I culled it. It came with russett mites.
Good luck AM, that is horrible.. we need to figure it out...no duh, huh. I will ask duck to come take a look.

We have been battling all kinds of bugs Rose. We have russet mites that we just completed a cycle of Green Cleaner on. Extra strength on the first application and normal strength for the final 2 applications. That was according to the directions on the bottle.

We have spider mites, grass hoppers, thrips, hemp bore moths (they leave a small larvae in the center of the stems and eat the plant from the inside out), botrytis (because of the way they breed here....I don't agree.

Please keep in mind that we are in 15,000sqf of greenhouse. High temps and bugs are a norm.

Thank you Rose for any and all help!
 
Have you used green cleaner before? I have a bottle but have not used it. So after hearing from you I am thinking russet mites. Those moths are here too, not yet, but i found if you see one dead fan leaf, look for that nasty boarer. That is where you find them.Cut them out, but i bet you know all that. What a nasty time you guys are having. Greenhouse thip i have heard of.. I can't really get all the way rid of them here. How about bringing in a bunch of beneficials. I really like the buglogical man, he helps me out a lot.
 
Is this just the one plant or are all of them being affected?

For one thing, I would expect that 120 degree temps would affect them adversely, even if it is for short periods.

Have you had your water analyzed to determine what the 300 ppm consists of? Large amounts of one element could be affecting others. My well water has arsenic and nitrates in it. I filter the water for my plants. https://www.amazon.com/gp/product/B01N8TYQ9W/?tag=skimlinks_replacement-20

I know in hydro if I have plants with leaves dying like that, it is often caused by root rot problems/res temps too high. You speak of a res in your greenhouse? What is that? I doubt that expired molasses would cause problems. Jugs swell because you have microbe activity going on in there, not necessarily because expired molasses is causing problems. Or did they go anaerobic? That could cause problems.

I'd also be for mulching the plants, especially since you have temps so high. It will slow the evaporation of the moisture.

I have never heard of rust as being a cannabis plant problem? What exactly is Rust?


In all honesty THG, this is only occurring in greenhouse number 3 (where my boss used the expired molasses). There are roughly 450 plants being affected.

Regarding temperature, there is nothing that can be done to lower the temps mid day. When its 95F outside it is 110F inside.

We have had our water analyzed and nothing bad came back. Some trace amounts of nitrates and arsenic were found, but not in high enough amounts to adversely affect the plants. The other 2 greenhouses are getting the same water and look beautiful.

Our reservoirs are only used for mixing nutrients, not for actual storage.

My opinion is that the molasses was bad and triggered an anaerobic explosion.

We have been considering straw to cover the top of the soil with, to slow evaporation. Mulch may work better...

Rust is just another systemic fungus that can wipe out crops quickly. It is a form of "blight".
 
Last edited by a moderator:
Have you used green cleaner before? I have a bottle but have not used it. So after hearing from you I am thinking russet mites. Those moths are here too, not yet, but i found if you see one dead fan leaf, look for that nasty boarer. That is where you find them.Cut them out, but i bet you know all that. What a nasty time you guys are having. Greenhouse thip i have heard of.. I can't really get all the way rid of them here. How about bringing in a bunch of beneficials. I really like the buglogical man, he helps me out a lot.

We use Green Cleaner regularly here. I would have to say it is our primary mite killer. However I have noticed the spider mites aren't affected by it. I really don't think we can ever get rid of all the bugs in here. It is just too big and way too open. The Hemp Bores are the least of my concern at this point.

I will most definitely go check out the Buglogical Man.
 
Rose, glad you are sharing the bug guy, lol. My first thought was russets, but now that AM mentioned the bad molasses, yes rust is a likely cause. It looks more like a disease than bugs.
 
Thank you Umbra, the bug guy talked me down. LOL, thank you for recommending him. I will use him more in flower. I have only seen rust in roses and it doesn't look like that. It is bright orange virus.
 

Latest posts

Back
Top