buy some mint plants

as you enter the side go 2 lanes and take a left (can't take a right)
then last one or 2nd to last one on the right has them

not far from the sharks in the small tank

10 or 15 a plant depending on size i think
or maybe that was price of other herbs, she usually have 5 to choose from

XinYuanLi across jinkelong at xanyuanqiao near hilton hotel. most taxi drivers know where it is. go to stall 100, she is the most decent n pretty honest so far.

if anyone still want some fresh mint plants, we have different types of mint, have a look: herbsgarden.cn

but we recomment to buy in spring cause it wont take long that the weather will be too cold for mints to grow properly, unless you are very skilled in keeping mint plants, better wait for the coming spring.

You can also find it in the Indian store in Sanlitun. Also there is one vegetable seller in the lane behind The Village who gives a lot of mint for just 1 RMB