Stem Rot?

[RalphWiley]

Being worth a thousand words and all, I might as well lead with a picture.

This cutting of Trainwreck was cloned in a homemade bubbler. It's a brand new bubbler and was one of the first cuts pulled, so I can't imagine any prior contamination. At any rate, I'm using Canna nutes with a bit of CalMag in Canna substrate, feeding at a PH of 5.8 or so (soil runoff is similar). It's under a 125W 6 lamp 2" T5. It's been growing quite a bit, but then I noticed it was getting weaker and weaker around the base of the stem. The problem is now visibly apparant, but I haven't a clue what it is. I've started spraying it with neem, but any suggestions or identification would be much appreciated.

Here's a Sour Diesel out of the same bubbler, same nutes, same substrate, etc that seems to be doing fine.

 

[Azra3l]

Hi,

IMHO looks like Fusarium to me.... It's due to a fungi that will develop if the soil is too wet with too cold night temp. If it's the case, there is nothing to do away from throwing away your cut and make another cutting.....


Peace

 

[RalphWiley]

Figured I'd post an update. I rubbed down the stem with hydrogen peroxide and it seems to have stopped whatever was happening. The stem is still weak in the spot, but the plant is putting out tons of new growth. I can't really bring myself to toss out a healthy plant, even if it's having a little trouble standing up straight, so I'm gonna leave it and cross my fingers.

The sour diesel had a pretty big growth spurt (this strain does that, I've noticed) so I pulled it out of the party cup (it was getting rootbound) and transplanted. Man, I love this strain! Potent, uplifting high, easy cloning, and grows like nothing.

 

[20kw dreams]

what strength are you using on that tw in the pic?

As far as your problem, try keeping the roots closet to the surface next time initially. Stem tissue rots much easier then root tissue.

 

[RalphWiley]

Thanks 20kw, I'll keep that in mind.

Using the standard Canna regime (4ml of canna A, canna B, cannazym and rhizotonic per gallon) with a bit of calmag thrown in. Visited my favorite local hydro shop today, and was told to spray everything in veg with a diluted sulfur mix to kill off the mold. Crossing my fingers it'll tackle the issue without putting undue stress on the plants.

 

[Guest]

id get some pirahna/tarantula or other bene bac. to add.
also raise the level of the soil above the wound

 

[Pedro_De_Pacas]

Hey whats up...

also raise the level of the soil above the wound

Good advice..Thats what id do...once you get that soil above that..and keep watering..after a week of two you will have new roots growing from there...and you shouldnt have anything to worry about..PEACE..

 

[Guest]

Hey whats up...
Good advice..Thats what id do...once you get that soil above that..and keep watering..after a week of two you will have new roots growing from there...and you shouldnt have anything to worry about..PEACE..

yea!!! exactly!! exposed tissue promotes rot growth, especialy if wet and dark...
do it!!!

 

[RalphWiley]

Thanks, guys! I've got to repot her (roots are starting to explore the holes in the bottom of the party cup she's in), I'll make sure to stick that part under the soil. She's still growing strong, I'm glad I didn't toss her at the first signs of trouble.

 

[HeadyPete]

I'm glad all is turning out well for you and your plant.

I agree with the burying the stem deeper. Works for tomatoes too.

 

[20kw dreams]

also raise the level of the soil above the wound

Good advice..Thats what id do...once you get that soil above that..and keep watering..after a week of two you will have new roots growing from there...and you shouldnt have anything to worry about..PEACE..

NO NO NO NO! Not Good Advice!

You have what is often refered to as DAMP OFF! This is from the medium and/or stem being kept too moist! Stems need dry conditions for proper osmotic processes to occur. Otherwise, they die from not getting proper nutrition and are attacked by disease. Stem tissue will develop Pythium, fusarium, rhizoctonia, phytophthora, when wet.

Healthy stem tissue may develop roots, but if a fungus is already present, then you are giving it optimal conditions which to thrive. Your stem is already weak and contains disease, wether it is recovering or not.

Heady Pete - Tomatoes are different, as they contain high amounts of auxins, which is apparent by the adventigious rooting along above ground stems. Tomatoes are naturally a spreading vine. Cannabis does not naturally root from stem tissue, as it grows vertically, and does not create heavy auxins in the stems which allow for as fast lateral rooting.

Don't get me wrong, I know you will get extra rooting points if you throw another node below the soil line. This works especially well if you scar and coat the stem in auxin (IBA, NAA). This is in fact why you don't need rooting hormone to root cuttings. In this specific case however, it would not be a smart move, as some kind of disease has attacked that tissue and you will only be aiding it.

I would guess you were watering too much, actually. Coco holds alot of air, so you wouldn't get the classic lack of DO symptoms, but the soil surface being constantly moist promoted fungal growth, apparently. Let your medium dry out a bit more before watering.

This may also be an indication of a larger problem though, as damp off is also an indicator of the above mentioned diseases being present in the medium.

If you want to take care of this, flush your medium with a high dose of H2O2, and I mean high, like 50/50 3% and water, let that sit for a day. It won't kill your plant, as I have used straight 3% with no problems. Then go out and get some beneficials, and innoculate with that.

The BEST innoculant you can find goes by the name "rootshield". It is T-22 trichoderma. It is kind of expensive, and not found in hydro stores. It is used by commercial greenhouses to control and prevent pythium, fusarium, etc. I used it on a couple thousand poinsettias, as well as a 6kw NFT grow. It is the only thing that got me white roots again after a nasty bout with pythium in that NFT system. I had rez temps of 65F, soaked the root balls in straight 3% H2O2, and a few different hydro enzyme and beneficial mixes like hydrogaurd, hygrozyme, cannazyme, organics alive, etc.

Trust me on this one. Although this specific case may not warrant all this worry, it is important people understand what these diseases are, how they work, and how to treat them or how NOT to treat them. In this case, putting the stem underground is how NOT to treat them
__________________________

 

[RalphWiley]

Thanks again for all of the help. The sulfur really seems to have done the trick, she appears very happy now and I'm not seeing any signs of reoccurance. I'll continue to treat (better safe than sorry), but I'm hoping this girl will produce some flowers for me. Here's a pic:

 

[20kw dreams]

she looks great. I didn't mean to scare you or anything, it's just imprtant to know whats really going on.

Healthy plants resist disease, so as long as thier healthy, you'll be fine. Just keep doin what you're doing.

If your using the coco straight, I would advise throwing in some perlite, like 1/3 or so. It helps to prevent the overwatering during rooting.

 

[jaypee89]

she looks great. I didn't mean to scare you or anything, it's just imprtant to know whats really going on.

Healthy plants resist disease, so as long as thier healthy, you'll be fine. Just keep doin what you're doing.

If your using the coco straight, I would advise throwing in some perlite, like 1/3 or so. It helps to prevent the overwatering during rooting.

That is true.

 

[RalphWiley]

Thanks, 20kw. I'm running about 20% perlite right now, which works out pretty well.