Can plants be left potted?

Probably, for a while, chances are they are planted in rockwool. When your ready to unpot them just peel away the rockwool like string cheese to avoid damaging the root system. Just keep in mind the type of plant. Root feeders won't be getting any nutrients from rockwool, as far as I know it doesn't absorb nutrients from the water column.

That's what it looks like to me. Can I just plant the whole thing basket and all in the substrait or should I just rubber band the stems then plant? What about those metal wright/ties on the other plants?

It's best to keep it neat and remove the rockwool from the stems and then plant in groups of three per hole. The lead weights are not suitable for long-term use because it's made of lead.

The weights will eventually damage the roots of the plant, so they're not suitable for the plant to keep it down.