[mumofstig]

If you look here http://www.dentalgentlecare.com/calcium_foods%202.htm

You'll see that the list of food that contains oxalic acid includes chocolate!
So not only should we avoid eating too much chard we must also give up chocolate
AS IF

[amckeen]

I had a bed with regular and rainbow chard plants in it for 3 years.  As the plants get older they seem to want to go to seed quicker but you can cut the long stalks off (picking off the small leaves that grow on them to use in salad).

And yes, if you cut the whole plant down to the soil level they will happily keepon producing.  I only dug mine up because I am reworking the layout of my plot.

Chard's great, plenty of goodness, versatile, but not as strongly-flavoured as spinach.