They should be plenty strong as raised beds because they have something of a superstructure built into the design to resist the outward force of water (and thus, soil).

Al

Thanks!

DL

I would not drill holes in the bottom, they likely are going to get clogged with all the soil etc hanging off them, and if some water sits in the bottom of the pool, it could be to your advantage....

I would use more or less, the principle of an earth box. Having some water in the bottom is a good thing, too much is not... The drainage holes should go in the sides, maybe 2 or 3 inches from the bottom. If the pool is level, perhaps drill a couple drainage holes on either side, Use a proper drill bit to prevent cracking. Then perhaps fit a piece of screen mesh over the holes. If the pool is not entirely level, then drill the hole on the side that slopes downwards.

This way, you can take advantage of rain, it will hold some of the water you put in, long enough to saturate the soil completely, but won't become totally waterlogged rotting out your roots.

Putting mesh over the holes is important, otherwise the soil will flow out.

Unlike an earthbox, I don't think it is necessary or desirable to create a water reservoir, and then try to wick it up into the soil... Just let some water collect in the bottom, but not too much... So the holes are more safety drainage...

I'm sorry Homemommy, but I have to strongly disagree with the concept and advice. It simply cannot be made to work w/o going through multiple inconveniences that would be completely unnecessary if the swimming pools had adequate drainage, which virtually every container gardener considers a necessity in all but very unusual circumstances.

Al

If you put the holes on the bottom, where is it going to drain? the weight of all the soil and water from rain / waterings is going to be very heavy, and it is likely unless the pool is on a hard surface, the bottom is going to sink into the ground. It is not going to drain effectively,unless perhaps you just about remove the bottom of the pool. And then I worry it is going to compromise the structure. the water is going to get backed up... even on a hard surface, I can see soil trickling down and blocking the holes. This has happened to me with my kids pool that I sometimes clean off tubers in. Even just a few buckets of dirt is enough to block the drainage hole on the bottom.

If the holes are on the side, the water WILL flow out. I am not saying to keep it a swamp!! If an inch or two of water being retained with the dirt in the bottom without much / any drainage will wick up very quickly through the rest of the soil, there are another 9-11 inches of soil above the drainage holes depending how close to the bottom they are put. It could probably lengthen the time between waterings required, especially because containers can dry out so quickly...

You Could start with a few holes, if it isn't draining properly, add accordingly...

I had a barrel with no drainage outside last winter full to the brim with sand. It filled up with water too over the winter, effectively replacing all the air between the graduals. My husband drilled ONE hole in the side near the bottom, and PRESTO, the water poured out with such force that it actually brought out a small wheelbarrow full of sand with it!! Now the hole is in place, it does NOT retain water, but because water does not build up, the pressure does not force anymore sand out either.

If you put the holes on the bottom, where is it going to drain?

Into the soil beneath the pot. Unless the pot is sitting on heavy clay, the ground will absorb any excess water. Lots of people bury pots in the ground for the advantages of temperature, moisture control, and temporary root run. It works just fine.

Having to water often = healthy roots.
Perched water table = dead roots.

Homemom, I think your wrong, holes in the bottom will allow the ground to act like a wick and help pull the water out. In fact I would cut a few holes the size of basketballs out of the bottom if I was doing it. If that pool held water, even a few inches you would have dead plants in a very short time. Theres few if any plants that the roots wouldnt find a way to the bottom and once there the plant would most definitely drown. I believe you have been mislead somehow. And one more thing I wouldnt use any soil at all in a container unless I cut the bottom completely out of the container. Even then I would use some kind of potting mix, or make my own planting medium. Good luck and may every seed you plant make you proud.
Plant em if you got em.
Sam

dancinglemons,
This may be one way to go for using your plastic pool.
Or try one this way and compare .
http://www.insideurbangreen.org/corrugated-drain-pipe-cdp-sip/
Scoll down to the Fire Escape Salad Bar example.
If you look around this site more you may even find an example using a wading pool.
Best of luck. I love my SIP's.

You want drain holes for sure.

I have seen a green house growing Indeterminate Tomatoes using 35 gal cans. The cans had NO holes at the bottom, the grower explained how he controls watering so rain will not over saturate his medium and root zone. He also went on a little and said how a container that is this large is better to not have drain holes.

You can not control when it rains so.

"He also went on a little and said how a container that is this large [35 gal] is better to not have drain holes."

IF that's what he said, he is SOOO full of beans.

Al

I know, his huge production of tomatoes that help pay his bills, they were full of beans too.

Sometimes I wonder if Al lacks practical knowledge. You just told me the person who owns a green house they are full of it? A person that has grown for 20+ years in greenhouses. If you can not understand that if you control watering. They make systems that have no holes at the bottum for indoor set ups. The are self watering pots with grow medium and no holes the bottum.

Please look that up Al. I said inside is much different then outside.