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Grey mold on stem

Nes

Nes

Member
Outdoor light dep in the PNW

Today we spotted gray mold patches that seem to be attaching the stems. Seems like the entry point is the older calyxs from preflowers on the node, then it spreads to the stem and eats away the cambrium, covering it in grey mold. We cut out 4 colas we found today :(

We're about 2.5-3 weeks from harvest, and its supposed to rain this week. any suggestions? we were thinking greencure, and hitting any further outbreaks on the stem with h2o2, cutting out effected buds.

any thoughts on what type of fungus we're dealing with and our plan of attack? suggestions? ideas for prevention in the future?

Thanks
Nes
 
SG1

SG1

Goblin Master
ICMag Donor
Veteran
I always have sulfer pistelles around for my sulfer burning needs for indoor powdery mildew treatments.

Last few years in the PNW has been difficult because of mold.
The stem attacking botritis literally starts eating the stem, then yellowing the plant above it.

Knowing that sulfer was used during WWl as an anti bacterial/anti-funguside, I figured I may have a solution.

I crushed the sulfer into a fine powder.
I used a pocket knife to scrape the mold off the stem, removing any soft dying stem.
I then rubbed sulfer into the wet wound.
Surprisingly, This stopped the aggressive mold attack.

I checked all my other plants and discovered more on a few plants.
I treated them before they showed any yellowing, and the sulfer stopped the mold.

I also found that the sulfer needs to be re-applied weekly to keep it from coming back to life.
Hope this is helpful
GL
 
MynameStitch

MynameStitch

Dr. Doolittle
Mentor
Veteran
SG1 said:
I always have sulfer pistelles around for my sulfer burning needs for indoor powdery mildew treatments.

Last few years in the PNW has been difficult because of mold.
The stem attacking botritis literally starts eating the stem, then yellowing the plant above it.

Knowing that sulfer was used during WWl as an anti bacterial/anti-funguside, I figured I may have a solution.

I crushed the sulfer into a fine powder.
I used a pocket knife to scrape the mold off the stem, removing any soft dying stem.
I then rubbed sulfer into the wet wound.
Surprisingly, This stopped the aggressive mold attack.

I checked all my other plants and discovered more on a few plants.
I treated them before they showed any yellowing, and the sulfer stopped the mold.

I also found that the sulfer needs to be re-applied weekly to keep it from coming back to life.
Hope this is helpful
GL
Click to expand...

Very nice SG1 :D awesome dude :tup:

Thats a nice idea too, how often does it rain there?
 
SG1

SG1

Goblin Master
ICMag Donor
Veteran
MynameStitch said:
Very nice SG1 :D awesome dude :tup:

Thats a nice idea too, how often does it rain there?
Click to expand...

Weather has been weird last 4 years.
Last year was the worst, rains started 1st week sept, didn't quit for long.
Normally get rain showers starting mid Sept, rainy season is full on by mid Oct. with cold temps to near freezing when it's not raining.
I usually have everything harvested 100% by mid Oct.

Mold will start without the presence of rain, right around mid Aug is the time to be watchful.
As soon as you see yellowing at the top end of the plant, that's the sign mold is already eating your plant.
Noobs sometimes mistake the yellowing for N deficiencies.
Seen a plant snap in half from mold damage.
I look for it, and make sure insides of plants are cleared of all non essential plant material.
 
MynameStitch

MynameStitch

Dr. Doolittle
Mentor
Veteran
SG1 said:
Weather has been weird last 4 years.
Last year was the worst, rains started 1st week sept, didn't quit for long.
Normally get rain showers starting mid Sept, rainy season is full on by mid Oct. with cold temps to near freezing when it's not raining.
I usually have everything harvested 100% by mid Oct.

Mold will start without the presence of rain, right around mid Aug is the time to be watchful.
As soon as you see yellowing at the top end of the plant, that's the sign mold is already eating your plant.
Noobs sometimes mistake the yellowing for N deficiencies.
Seen a plant snap in half from mold damage.
I look for it, and make sure insides of plants are cleared of all non essential plant material.
Click to expand...


ah ok, thanks for that info Did not know . Ya learn something new everyday :D

I can't imagine dealing with a lot of plants outdoors with rainy weather I would end up losing sleep at night lol
 
D

DoubleDDsNuggs

I was gonna hold off on commenting until someone else suggested it because I wasn't sure but I was gonna say sulphur. since I'm bored as hell and was curious about the differences in copper sulphate and sulfur, I found this info:
"Copper-based compounds (Monterey Liqui-Cop)—There are many copper products, but fixed copper sulfate is the one most gardeners will find. Bordeaux mixture, made by adding copper sulfate and calcium hydroxide to water, was the first fungicide. It still is used extensively in France to control downy mildew on grapes. It is a highly effective fungicide that stays on the plant surface even after several rains. Usually it is used as a dormant spray as it may burn young tissues. The copper most commonly obtained is labeled for use on many fruits, nuts, ornamentals, and a few vegetables. It controls many fungal and bacterial cankers, galls, blights, and leaf spots. Experts recommend copper for many plants and diseases not listed on labels because the federal agencies have decided that no tolerance levels need to be established due to copper’s low toxicity and insolubility in water"
http://pnwhandbooks.org/plantdisease/node/1840/print

I'm really sorry about you finding this after everything you've overcomed during this grow. I thought for sure this was gonna be the year for PNW. I'm not sure how much other coper sulphate products are but dutchmasters zone is around $30 but the application rate is super low.
 
chilliwilli

chilliwilli

Waterboy
Veteran
can u put some kind of cover above the plants to keep direct rain away?
like a little carport made of plastic foil
p.s. like u profile pic sepp holzer has some good idea for growing. sad that he is no ganjagrower
 
Last edited:
Nes

Nes

Member
Thanks SG1! I'll try it tomorrow!
You're description is dead on. it slowly girdles the branches, starting right around the node. as soon as it has worked its way around a branch, everything uneffected above it starts drying on the stalk. It started before the rain too. I'll try a sulfur paste tomorrow.

Thanks doubleDD, i figured i'd go to the store tomorrow and see what was available. I'll look at copper sulphate.

chillwilli, we did that today, but as SG1 mentioned, it occurs regardless of rain. hopefully it helps slow it spread though, and helps it dry so we can treat it.

Thanks everyone for all the input and help!
 
Nes

Nes

Member
SG1, any thoughts on sealing some of the bigger wounds once applying the sulphur? I was thinking about wrapping the wounds with grafting tape where it was possible to try and keep anything from entering there, after applying the sulphur paste.
 
SG1

SG1

Goblin Master
ICMag Donor
Veteran
I apply the sulfur dry in powder form.
The moisture of the wound makes it stick.
I suggest keeping it exposed to the air, at least I did.

Just re-apply in powder form as often as you see fit.
If over 1/3 of the stem is molded, then it's best to splint the stem with some sticks and string to strengthen.
Normally just the outer skin is damaged.
If it goes deeper, then splinting is warranted.
The stem will scab up when healing.
 
Nes

Nes

Member
awesome, thanks! The garden store didn't end up having the grafting tape, anyways. I don't know why i thought i read that you chopped it up and made a paste, maybe i confused rubbing it the wet woulnd. We got the dustable/wettable sulfur powder. I ended up mixing it in a cup with a tiny bit of water and applying it to the effected areas with a q-tip. The paste on the q-tip worked as as abrasive and took the spores and surface mold off, then we hit it with another layer of the paste. The paste seemed to dry in place leaving a chalky layer of the powdered sulphur caked on.
I guess I slightly misinterprited your application technique, but I think I got the jist of it and it seems like it'sworking so far! We'll keep our fingers crossed.
Thanks again SG1!
 
Nes

Nes

Member
Thanks y'all. So It's all down now, and I'm back to report on this issue.
For botrytis on the stem, the dustable wettable sulfur works great. We threw some in a cup with enough water to make a paste and applied it with a q-tip. The granular nature acted as an abrasive, scrubbing the mold away. Then we'd apply another coat to cover the wound in the paste. Sometimes we spot treated with h202 in a spay bottle before the paste, other times we didn't, it seemed to work either way. Since the botrytis on the stem attacks the cambrium, it only really helped if we caught the spot early, before the branch was girdled. Girdled branches died above the wound, but we only had a couple little ones get hit that bad.
This wont stop botrytis from persisting though. an affected area the size of a fingernail is supposed to have more than 6,000 spores... If the conditions are right, it will keep popping up in spots, but this allowed us to push an extra couple weeks without loosing much. It did present in a few more spots after we started combatting it, and we had to cut out a couple buds, but we were able to save entire colas and branches. In one case we caught it low on a branch that would have taken out half a plant, and saved it.

I'd say this is a worthwhile technique to keep round. I'd recommend it.
 
SG1

SG1

Goblin Master
ICMag Donor
Veteran
Nes said:
Thanks y'all. So It's all down now, and I'm back to report on this issue.
For botrytis on the stem, the dustable wettable sulfur works great. We threw some in a cup with enough water to make a paste and applied it with a q-tip. The granular nature acted as an abrasive, scrubbing the mold away. Then we'd apply another coat to cover the wound in the paste. Sometimes we spot treated with h202 in a spay bottle before the paste, other times we didn't, it seemed to work either way. Since the botrytis on the stem attacks the cambrium, it only really helped if we caught the spot early, before the branch was girdled. Girdled branches died above the wound, but we only had a couple little ones get hit that bad.
This wont stop botrytis from persisting though. an affected area the size of a fingernail is supposed to have more than 6,000 spores... If the conditions are right, it will keep popping up in spots, but this allowed us to push an extra couple weeks without loosing much. It did present in a few more spots after we started combatting it, and we had to cut out a couple buds, but we were able to save entire colas and branches. In one case we caught it low on a branch that would have taken out half a plant, and saved it.

I'd say this is a worthwhile technique to keep round. I'd recommend it.
Click to expand...


I look for stem rot in mid july, when I find it, on goes the sulfer.
And you are correct, it doesn't kill it 100%.
But if you're looking to postpone the inevitable, buy that extra 4 weeks, save that vulnerable branch, then works great.

Not bad for a brain fart experiment :tiphat:
Necessity is the mother of invention.
Glad it helped, pass it forward.
 
br26

br26

Active member
Beneficial fungus as a foliar? Been doing that to fill the niche of topical fungal protection. Lil ' molasses to be the food and a surfactant to resist attacks from not only bugs but pathogenic fungi.

Wrapped copper around the trunk of some plants this year becuz o' slugs. It is an old remedy. Dunno if that helped the fungi issue, coudn'ta hurt.
 
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