to clarify: it's semi-rigid, not super rigid like the clear type of bins. Hmmm, come to think of it, it's like the rubbermaid totes people use to make self watering containers. How long do those last for people?

Try freecycle or craigslist for a scrap metal piece.

The plastic will last for awhile before cracking. I've used a sterlite brand large tote for a worm bin outside year round for at least 10 years. I have garden buckets from commercial suppliers from pickles, sour cream, mayonaise, etc. that are still water tight. The worm bin lid is a bit cracked from opening & closing.

The roughneck Rubbermaid totes seem to last forever & put up with a lot of handling. None of ours have ever cracked despite rough use & some were even used as sleds when our kids were little.

Remember where it is by leaving a bit of it out of the soil/mulch, so you don't shovel into it.

Thanks for the reply, Corrine. I've been looking at craigslist but haven't seen anything and figured freecycle would take a few days (if at all) and I wanted to plant tomorrow so I'm just using what I got. That's a great tip for leaving some of it above ground, I wouldn't have thought of that issue coming up.

Now just gotta deepen that trench, ughhh....