I have several questions regarding a popular Chinese vegetable. For information purposes, I have attached a picture of the plant 
- I would like to know why the leaves are bitter and whether they are edible?
- If edible, is it possible to remove the bitterness in the leaves?
PS: I have adjusted the title. The plaant is also called mustard greens.
Best Answer
Bolted?
This is a mustard related to bok choi, napa cabbage etc. If mustard (or many other leafy plants) bolt and set flowers they can become bitter. One would think that they would not then be sold, but sellers can cut off the flowers and hope no-one notices. I once bought some like this at the farmers market and a different seller caught sight of it and pointed out where the flowers had been cut off.
I am not super averse to bitter so I ate it anyway.