Christine ~ try planting it in late summer, early fall. Mine has stayed in ground all winter, shaking off the frost. I have grown two types, one is Bright Lights. I'd have to look at the other seeds for a name. I think the thicker stemmed chard types are more durable than the thin stemmed. And I like to eat the stems so thick is better there too.
Isn't Oxalic acid bad for those that suffer with gout or other forms of arthritis? I knew Asparagus was a culprit but didn't realize that about chard.
Kristi