Try straw mulching the Swiss Chard. On my south side, I have had Swiss Chard go right through the winter. Like beets, it is biennial. It needs a 2nd season to make seeds. Try to get it to go through the winter. You can still go out and snip off leaves to eat.
Beets and kale also do well with straw mulch. Mine are on the north side of the house, so not as warm as where I had the Swiss Chard. I have used leaves around beets. Leaves are not as good because they pack down, but I have done okay with them. Parsnips live through anything. There is a reason Swedes eat them so much! They survive cold and reseed themselves!
