Nutrient dosing and watering an outdoor 300 gallon soil container

[PurpleLurple]

I will have two cannabis plants in one 300 gallon container which has about 250 gallons of soil (bottom layer is drainage layer of plastic bottles, etc).
I want to use Jack’s outdoor 18-8-23 nutrients next year; do I base the dose on how many gallons it takes to saturate that 250 gallons of soil? For instance, the nutrient dosing directions may say 1 tablespoon per gallon of water. If it takes 20 gallons or more to saturate the soil would I then use 20 tablespoons in 20 gallons of water? It seems like so much for two plants. I always worry about over feeding and so far in two grows I’ve underfed both times, but at different times. Live and learn. That’s the fun of it for me. Oh, and the end product. Lol. If my understanding is incorrect, please tell me how to dose for such a large container? Also, I have read the watering stickies on this site, but I would love for somebody who has grown in a large soil container outdoors to guide me on proper watering procedure and nutrient dosing procedures. Thank you all in advance for any advice.

 

[mysticepipedon]

I will have two cannabis plants in one 300 gallon container which has about 250 gallons of soil (bottom layer is drainage layer of plastic bottles, etc).
I want to use Jack’s outdoor 18-8-23 nutrients next year; do I base the dose on how many gallons it takes to saturate that 250 gallons of soil? For instance, the nutrient dosing directions may say 1 tablespoon per gallon of water. If it takes 20 gallons or more to saturate the soil would I then use 20 tablespoons in 20 gallons of water? It seems like so much for two plants. I always worry about over feeding and so far in two grows I’ve underfed both times, but at different times. Live and learn. That’s the fun of it for me. Oh, and the end product. Lol. If my understanding is incorrect, please tell me how to dose for such a large container? Also, I have read the watering stickies on this site, but I would love for somebody who has grown in a large soil container outdoors to guide me on proper watering procedure and nutrient dosing procedures. Thank you all in advance for any advice.

Yes, it would be 20 tbsp in 20 gallons. Yes, that is a lot.

When dealing with large quantities of soil, dry nutrients are usually a better choice. Something else to consider is why you have two plants in 250 gallons of soil. How long do you have to veg to get a plant to explore 125 gallons of soil? a year?

 

[PurpleLurple]

I had three in it this year on a scrog and it is really one plant too many for the screen. I have them in there because that is what is available to me. I also have two 100 gallon containers that both have 2 plants each on a scrog. I used dry nutrients this year but still screwed up transition to flower. I guess I’ll stick to dry. Do you recommend removing dirt from that container and using more filler bottles to achieve lesser volume of dirt? I’ll be curious to see how much root zone they filled in that container. Thank you

 

[2Bad]

Following because its interesting. Hope we get a pic soon.

 

[beluga]

I'm guessing the plants in your profile in the galvanized tub are the ones question?

As of that last picture, they look like they're good with whatever the soil composition is.
It will be hard to calculate any top feeding, I'm not the guy to answer that part. I agree with mystic, though, dry is the way to go.
How did you mess up the flower transition?

 

[PurpleLurple]

Yes these are this years. I think I put way too much bat guano in my amendments, didn’t activate the soil, and at the end of veg they were really dark green, then nute burn, then I didn’t add enough K or P and had deficiencies—plus maybe some lockout from N. Maybe I will compartmentalize my big container into several smaller containers and water less and when I get it right that would be much smaller volume of dirt to feed.

 

[mysticepipedon]

Well, for next year...

I'd mix the dry fertilizer with the soil. You may not need to feed for 5 weeks. Then I'd top dress generously.

 

[PurpleLurple]

Ok cool. Thank you very much. Just didn’t time my top dressing right this year