container Pots for Pennies - Roots and container size

AJ Drew · Jun 30, 2015

Have always felt pot growers were the pioneers of indoor growing. So have read many an article and book on the subject. One, Pot for Pennies, was very helpful. One of the things it recommended was cutting the top of 2 liter pop bottles and cutting holes in the bottom.

Previously, I used solo cups at that stage of development and thought I was doing fine. In my trays, I can fit about 24 solo cups per tray. With the 2 liter bottles I can fit about 20. So I do not loose all that many spots in my grow system. What I gain is tremendous depth.

So everything is transplanted and I have noticed the plants that were in 2 liters are kicking ass over the solo cups. Now of course the bigger size probably helped, but I think the depth might be responsible as well. Peppers do not love moisture like other plants and I bottom water. Thinking maybe being so much taller, they wick a bit less water to the developing roots.

Thoughts? Could two liter bottles be that much better than solo cups despite taking up just a tiny bit more room?

BTW: Have kids who love soda, so 2 liter bottles are free. Solo cups are not something we would otherwise ordinarily purchase, so it is great for us cheap bastards to recycle.

Vicious Vex · Jun 30, 2015

It certainly would help when transplanting later. Also would allow for accurate tracking of root depth and transplant time.

Maybe you are on to something with an idea of someone selling clear pots. Keep an eye on root bound plants when growing indoors before last frost.

Ideas brewing on my end.

OT: I believe it is related to root depth more so than the watering. Deeper roots= more absorption of critical growth nuts.

moruga welder · Jun 30, 2015

i put a few in 2 liter bottles , but the ones i had in the 1 gallon pots grew much better . tho it was cool watching the roots grow . :onfire:

Vicious Vex · Jun 30, 2015

moruga welder said:
i put a few in 2 liter bottles , but the ones i had in the 1 gallon pots grew much better . tho it was cool watching the roots grow .

Just had an idea for half gallon milk jugs. Same theory, built to optimize space in thr shape of a rectangle. I drink milk, so it would be a free venture. Not to mention the added bonus of a handle for moving.

juanitos · Jun 30, 2015

i dont understand how you can fit 20 vs 24 solo cups... 2 liters are a lot bigger.
any round pots are wasteful of space imo

AJ Drew · Jun 30, 2015

Juanitos, I am using mortar trays from Lowes. Due to the size, I wind up with enough room to fit another row of solo cups if they were about half the width. The 2 liters fill it perfectly so a bit less wasted space. I dont think on a table surface the same would be true at all.

Vicious Vex · Jun 30, 2015

ajdrew said:
Juanitos, I am using mortar trays from Lowes. Due to the size, I wind up with enough room to fit another row of solo cups if they were about half the width. The 2 liters fill it perfectly so a bit less wasted space. I dont think on a table surface the same would be true at all.

I will do the math tomorrow. I'll figure out how much space is lost over a general area.

AJ Drew · Jul 1, 2015

Vex, not sure math will work if you are just measuring surface area. When four circles match up there is a diamond shape of empty space. Is why so many people advocate square containers. With smaller cups, you have more of those diamonds but they are smaller. With the bigger two liters, slightly more space but less of them. In my case, the main factor is what fits into the trays.

BTW: Lowes changed the size of their trays by maybe an inch not long ago. Screwed me all up cause I built rack after rack to hold them the way they were originally.

Vicious Vex · Jul 1, 2015

ajdrew said:
Vex, not sure math will work if you are just measuring surface area. When four circles match up there is a diamond shape of empty space. Is why so many people advocate square containers. With smaller cups, you have more of those diamonds but they are smaller. With the bigger two liters, slightly more space but less of them. In my case, the main factor is what fits into the trays.
BTW: Lowes changed the size of their trays by maybe an inch not long ago. Screwed me all up cause I built rack after rack to hold them the way they were originally.

Measured a 2 liter bottle, and the space it occupies (2D surface area), and then subtracted that from the diameter of the bottle squared.

So DIA^2-(SA of Bottle)

Surprisingly. There is minimal space loss in comparison. A majority of the space difference is coming from the increased diameter of the bottles.

I still think half gallon milk jugs would work better.

And my dad thought my engineering degree was gonna be a waste

AJ Drew · Jul 1, 2015

Vex, holly crap that makes sense and it is just right there. Think of the bottles as squares and you have covered that diamond area of empty space.

On milk jugs, starting to wonder about the half gallon size. Thing is, if I start saving any more trash I might wind up in divorce court.

Nuclieye · Jul 1, 2015

The 1/2 gallon milk jugs for pots are a good idea for sure. Here we have to also consider humidity levels so right now all of my new starts for the fall/winter grow are also under the tops of the recycled containers I use. Milk jugs around here are not clear so light is starved. I'm using "Simply Orange" juice jugs for bottoms and the humidity domes. To harden off I remove the caps and lowers the humidity a little inside. The when the monsoons hit (like now) I remove the bottle top and they are good to go.