20 litre pots

Just a quick couple of questions - would it be possible for a marijuana plant to become root bound in a a 20 litre (5 US Gallon) pot? And if yes, how long do you think it would take and how big would the plant have to be for it to happen?

Depends on many things but yes.
I have 4 outdoor plants in 25L pots
They are pretty much root bound (tiny bit more soil left in the pots).

LOL, been considering making the pots taller with duct tape.

Just for interest sake.
This plant (she has been trained all her life) is now standing at about 1.9 meters (including the 25L pot).

I dont buy into root bound plants. I grow 12/12 from seed in 1 gallon pots and yield 2-4 ounces each. Not saying it doesnt exist just saying I have never seen it.

Anotherlover said:

LOL, been considering making the pots taller with duct tape.

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Ha ha! I like ideas like that.

it do exist, and suck to have in flowering:



top pot is a 5 gallon, bottom one is 3 I believe, had a Violator Kush going with a Veg time of +8 weeks the pics is 3 weeks in to flowering

Edit: and yes I did cut out the bottom of the top pot

What were the signs of root bound?

bigv1976 said:

What were the signs of root bound?

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With mine the roots are about 5mm from the top of the soil and sticking out the drain holes at the bottom.
I now also have to water every 1.5 days or they go droopy (as in the pic).

Yeah I dont see that as root bound. I water every day any way.

I killed two recently.

They went into the big pots mid December. For December I was watering them about every 3 to 4 days with no stress.
Beginning Jan I killed a male. Roots filled the whole pot, not quite pot bound yet but more root matter than soil (I take the roots apart when I kill them out of curiosity).
January I had to water them every 2n'd to 3'rd day.
In February I killed a hermie. About 90% root matter, almost no soil.

With my 4 I have left there is about 5mm of soil on the surface and everything below that is pretty much root matter (I have to cover the roots after each watering).

bigv1976 said:

I dont buy into root bound plants. I grow 12/12 from seed in 1 gallon pots and yield 2-4 ounces each. Not saying it doesnt exist just saying I have never seen it.

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I would probably have totally agreed with you before my current grow. I believe I have experienced it now though.

I've certainly had it in the small cup pots I start my plants off in. Noticed it properly this grow. Left some sugar punch in them for way longer than I usually do (4 weeks) and the lower growth yellowed badly, couldn't throw enough Nitrogen at it in the feed to address it. When I re-potted into the 20 litre pots the entire soil was a root ball (well, that's what it looked like anyway - whole pot was root). Starting to see the same thing now with a 3 week old Kolossus in the same small cup pot - I know Kolossus to be hardcore tolerant to nutes though, so have just thrown some serious 'BioBizz Grow' and 'Bloom Cal/Mag' at it (1.5 times max recommended dose of both) to see if I can reverse the symptoms (really yellow first leaves). A 20 litre pot is waiting for her should it not.

Thing is, the Sugar Punch girls have been vegging for 10 weeks now - 6 in the 20 litre pots - under 250W CFl. They are huge trained bushes. The biggest one is 34 inches wide, and pretty much round now, so that width all the way. They will be getting at least another 4 weeks veg before I flower them under 600W HPS. And it is this which has me wondering if they will become root bound. As I am sure these girls will be 5oz+ yielders and really wide trees by that point.

Like I said I am sure it exist I just havent seen it in my 1 gallon pots with the 3' plants in them.

Anotherlover said:

With mine the roots are about 5mm from the top of the soil and sticking out the drain holes at the bottom.
I now also have to water every 1.5 days or they go droopy (as in the pic).

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I have a 4ft 6in hazey sugar punch girl flowering now in a 20 litre pot that is taking a full water/feed every 3 days. Her sisters are only needing it every 5/6 days. Not seen anything like it before myself. Not saying this one is root bound - she was only vegged for 4 weeks, now on week 6 flower - but she has certainly filled up her environment and is utilising it more than the other two phenos.

Certainly makes me feel like I should consider how other plants of this strain might react in the same environment if trained and vegged for 4 times longer. I think I need to invest in some super size pots and more soil before I put these vegging ladies in my bloom tent.

bigv1976 said:

Like I said I am sure it exist I just havent seen it in my 1 gallon pots with the 3' plants in them.

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I didn't mean to suggest that your contribution was wrong, don't think I did either.

Bigby said:

I didn't mean to suggest that your contribution was wrong, don't think I did either.

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I just didnt want you to think I was telling you that you are wrong.

bigv1976 said:

I just didnt want you to think I was telling you that you are wrong.

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Thanks dude.

That's what I was doing with my last post too. Both our observed findings are of equal merit.

Absolutely.

Bigby said:

I have a 4ft 6in hazey sugar punch girl flowering now in a 20 litre pot that is taking a full water/feed every 3 days. Her sisters are only needing it every 5/6 days. Not seen anything like it before myself. Not saying this one is root bound - she was only vegged for 4 weeks, now on week 6 flower - but she has certainly filled up her environment and is utilising it more than the other two phenos.

Certainly makes me feel like I should consider how other plants of this strain might react in the same environment if trained and vegged for 4 times longer. I think I need to invest in some super size pots and more soil before I put these vegging ladies in my bloom tent.

Click to expand...

My smallest outdoor plant would be around that height if it was not for me shaping them to keep height down (took about 40% of the height off her by bending main stem during veg).
Currently including the pot my tallest plant is just over 2 meters (About 6.5feet) as of this morning. She was also heavily shaped during veg and actually had her main stem snap at one stage. She would be over 2 meters without the pot if I did not shape her.

The issue that concerns me regarding this now is - how do you transplant a trained plant that is in a 20 litre pot? I imagine it will be tricky to turn her out of that, I mean I struggle with 8 inch pots - plus then there is the issue of the tie downs from the training.

Considering getting some 39 litre Rhizo pots, and trying to move them into there - but really feel the transplant could be a job beyond me.

Have you contemplated double potting like the user on the first page?

IME though I've never seen a root bound plant in nearly 5yrs of growing.

I use 11L pots with 3weeks veg and 8-10weeks of flowering.

I do use coco though so this could explain it.


To double pot a plant, get your new pot ready and filled to the top.

Pre-soak it,

Cut the bottom off your existing pot and bury it about an inch or do down into the new pot.

Least stressful way. IMO.



J