Leaves Going Brown

[Canresearcher]

Ok, well less frequent waterings isn't a problem. I can go by the way I've been doing it all along and wait another day or two with the itchy trigger finger. I've just gotten it this far and I don't want to mess it up now. Thanks for the advice, for sure.

Actually the dolomite lime suggestion works quite well. CaCO3 (calcium carbonate)... It's good to raise the pH up and provide Ca+.
Cannabis generally wants ~6.2-6.8 range anyways. Close to neutral to very slightly towards alkaline.

Again, I'll re-iterate what you're experiencing is more likely a nute-burn just like what is occurring in the pic below. (diagnosis for below plant was excessive Urea/Ammonium salt buildup which was being supplied by Bat Guano) It's hard to know 100% what might be occurring unless we can physically test your soil. There might be several things going on at the same time which would lead to a bad diagnosis.

Questions for you:
1) What are you using in way of Nitrogen?
2) What source of Potassium are you using?
3) What source of Phosphorous are you using?
4) Please disclose anything that you are using other than molasses.
5) Are you trying to feed Mycorrhizae with Molasses?
6) Are you using Promix HP by any chance?

7) Do you have access to a pH test kit? It might be a good idea to check the run off.

I don't think it would hurt to try a tiny small handful of Dolomite around the base of the plant and see what happens. Also, to be absolutely sure stop using the molasses for a while ( as others have suggested) .
In 2-3 weeks have a look at the new growth and get some pictures.

I'm not sure what else to recommend.

 

[flytier]

OK guys, let's see what we can do here. I picked up a single-use soil test kit from Walmart today and I'm going to read the instructions tonight, and give it a whirl tomorrow. It tests pH, as well as N, P & K levels.

So here's what I can tell you from your questions and comments:

- I haven't been using Epsom salts for about 2 weeks now;
- I don't have any lime available to use but I have white gypsum, aka calcium sulphate, that I can powder up;
- For nutrients I'm adding molasses and coconut water;
- I'll stretch out my watering intervals by a day or two;
- I'm not using any nitrogen that I'm aware of;
- The potassium I'm using comes from molasses and coconut water;
- The source of phosphorus is bone meal - I may need some more of that, as I just sprinkled a bit on the surface of the soil;
- My reason for using molasses is to feed the microbes;
- Never heard of Promix, but I have some Miracle-Gro for flowers, 15-30-15 that I can use if needed.

Thanks for the help guys, really appreciate it.

 

[Canresearcher]

OK guys, let's see what we can do here. I picked up a single-use soil test kit from Walmart today and I'm going to read the instructions tonight, and give it a whirl tomorrow. It tests pH, as well as N, P & K levels.

So here's what I can tell you from your questions and comments:

- I haven't been using Epsom salts for about 2 weeks now;
- I don't have any lime available to use but I have white gypsum, aka calcium sulphate, that I can powder up;
- For nutrients I'm adding molasses and coconut water;
- I'll stretch out my watering intervals by a day or two;
- I'm not using any nitrogen that I'm aware of;
- The potassium I'm using comes from molasses and coconut water;
- The source of phosphorus is bone meal - I may need some more of that, as I just sprinkled a bit on the surface of the soil;
- My reason for using molasses is to feed the microbes;
- Never heard of Promix, but I have some Miracle-Gro for flowers, 15-30-15 that I can use if needed.

Thanks for the help guys, really appreciate it.

I'm getting a clearer picture now of what might be happening to your plant.

For calcium you can use also Tums as well to raise the pH if the soil medium is too acid. This is Calcium Carbonate with a little medical grade silica added in. It'll work just fine.
If you've got Gypsum use it instead, and you're on the right track with that.

You want to make sure your soil is inoculated with Mycorrhizae before feeding the soil with sugars. Not all soil has it as there is a great deal of bagged soil that is sold completely sterile.ie) Cooked at high temperatures for hours. That's why Promix HP is so good as it has the beneficial fungus already added.

Be very careful when using miracle grow for flowers. Rule of thumb use 40-45% conc. than what is recommended on the box. (less is more) You have double the P4 than N2 or K which can encourage early flowering. At your stage you want the plant to grow up and veg as much as possible then flower once large enough. Vegetative growth is determinant by Nitrogen (N2) as it's a macronutrient.
It seems that you may actually be deficient in N2 from the sounds of things from what you've explained.
Potassium will be in trace amounts in coconut water and molasses. You're more than likely going to need a stronger source. Dried banana skins powdered up can deliver enough K to work as a fertilizer. (The key is to get the banana skins completely dehydrated.)

If it were me I'd stop using the molasses for the time being.


Hope any of this helps you.

 

[flytier]

Alrighty, this is what I can tell you from the soil test. Bear in mind I can't give you a whole lot of numbers, as it's just a basic colorimetric titration kit:

- pH is at about 6 or so;
- N is quite high;
- P is quite high;
- K is kind of middle of the road.

During flowering, the P is supposed to be high anyway, right?
What can I do to lower the N?
Should I try to raise the K?

I was looking around last night for my chunks of gypsum but I couldn't find them, so how about if I look around to see if I can find a chunk of drywall? Or if need be, I can add Tums. I may have to go to the pet shop and get an aquarium pH test kit on payday (Friday) for multiple-use tests, rather than but a bunch of single-use soil kits.

As for Miracle-Gro, I've only been using it at 1/4 strength right from the beginning, and I discontinued it a month ago or so.

I doubt if the soil is inoculated, as it's just plain old potting soil. It was bought before I started gaining knowledge as to what to use. My next plants are in a mixture with fish compost that I made myself at work last year, so I'm quite sure they'll be able to handle the molasses. I can add a layer of it to the surface of the pots these plants are in to give it sort of a booster shot and let the microbes leach down into the soil. Actually I can do that right now. When I did the soil test it was quite dry and ready for a watering. Better late than never.

I may be able to get some water from a biofilter at work. It contains nitrifying bacteria which breaks ammonia down to nitrites, then breaks nitrites down to nitrates. Not really sure what the nitrogen compounds are in the soil.

That's what i can tell you for now. It should get us another step or two to a solution. You know, I can put 10 million salmon through the hatchery in a year, but I can't grow two weed plants! Frustrating. Once again, thanks a lot.

 

[Canresearcher]

Alrighty, this is what I can tell you from the soil test. Bear in mind I can't give you a whole lot of numbers, as it's just a basic colorimetric titration kit:

- pH is at about 6 or so;
- N is quite high;
- P is quite high;
- K is kind of middle of the road.

During flowering, the P is supposed to be high anyway, right?
What can I do to lower the N?
Should I try to raise the K?

I was looking around last night for my chunks of gypsum but I couldn't find them, so how about if I look around to see if I can find a chunk of drywall? Or if need be, I can add Tums. I may have to go to the pet shop and get an aquarium pH test kit on payday (Friday) for multiple-use tests, rather than but a bunch of single-use soil kits.

As for Miracle-Gro, I've only been using it at 1/4 strength right from the beginning, and I discontinued it a month ago or so.

I doubt if the soil is inoculated, as it's just plain old potting soil. It was bought before I started gaining knowledge as to what to use. My next plants are in a mixture with fish compost that I made myself at work last year, so I'm quite sure they'll be able to handle the molasses. I can add a layer of it to the surface of the pots these plants are in to give it sort of a booster shot and let the microbes leach down into the soil. Actually I can do that right now. When I did the soil test it was quite dry and ready for a watering. Better late than never.

I may be able to get some water from a biofilter at work. It contains nitrifying bacteria which breaks ammonia down to nitrites, then breaks nitrites down to nitrates. Not really sure what the nitrogen compounds are in the soil.

That's what i can tell you for now. It should get us another step or two to a solution. You know, I can put 10 million salmon through the hatchery in a year, but I can't grow two weed plants! Frustrating. Once again, thanks a lot.

Yes, I can say that P4 must be higher during the flowering stage as this will help continue the bloom until finish,
I'd personally stay away from using drywall as a gypsum source one is never quite sure exactly what you're getting. Can and frequently does contain extra additional chemicals ( fire retarder, Silanes etc...) Pure gypsum from a agricultural supply store or ceramics store is a MUCH better idea. The tums idea is going to be a much safer bet, though it's just not in Sulphate form.

 

[flytier]

Yes, I can say that P4 must be higher during the flowering stage as this will help continue the bloom until finish,
I'd personally stay away from using drywall as a gypsum source one is never quite sure exactly what you're getting. Can and frequently does contain extra additional chemicals ( fire retarder, Silanes etc...) Pure gypsum from a agricultural supply store or ceramics store is a MUCH better idea. The tums idea is going to be a much safer bet, though it's just not in Sulphate form.

Ok. That's not a problem since the soil's a bit acidic anyway. I have tomorrow off so I can acidify it a bit with some coffee grounds when I'm done my first pot haha. I also put an inch of fish compost on the top of the soil to inoculate it a little.

 

[Suntana]

Don't forget you calcium, that will help bring your ph up.

 

[flytier]

I was into the farm supply store today and found some dolomite lime in there so I bought a bag. I'm assuming that I probably don't need all 13 kg of it right haha? But for 4 bucks ya can't go wrong. The plants have been looking better since I stopped killing them with kindness. Bear with the crappy photography:

Getting some nice trichomes now too:

Every day they're getting closer.