For me it's common for the plant to flower. Usually, when the plant produces flowers I just get rid of it. I read somewhere that when you plant the seeds from the Okinawan spinach, the end product will be in its original form; the desired purple color of the leaf will be all green.

Here is an image from from Forest and Kim Starr:
{{gwi:881360}}
If you don't want "weeds" popping out all over your garden, it will be a good idea to cut off the flowers.

thanks randg. i might let a few seeds sprout just to see what grows.

i already have quite a few weeds so one or two more won't hurt ; )