I've never grown vegetables.

But I'm not sure I understand the question.
You have this bed on concrete? Pool cover for a liner? Is it filled with soil now? or is it just like an empty swimming pool? Does it have drainage?
Plant peat pots full of seeds into soil, or ??
Could you clarify this some?

Karen

I built my raised bed from lumber on my concrete "backyard". I have about 9 inches of soil and compost in it now, and lots of late-growing plants. (I started gardening for the first time in late July.)

The pool liner was cut to fit the bottom of the bed and sides to prevent the dirt from washing out onto the concrete during rainstorms, and to aid in retaining moisture. I have just a little drainage for it that seems to be sufficient for all the plants that I have growing in the bed right now.

I wondered if I could WS my seeds into peat pots and put those pots right into the soil, so that I wouldn't need to keep re-potting them as they germinate and grow. I thought maybe I could put a 2-Litre bottle over each peat pot to protect the seedlings as they grow. Would this work? Or do I need an enclosed mini-greenhouse like a container or ziploc baggie?