I have wanted to grow it. I have tried to grow it from pieces I got in the produce section of a local Asian market without success. Given @naf 's success, I will try again. Seeds I’ve seen online (Etsy? ) seemed expensive.
I found this WorldCrops link with information including other names interesting. I think it was labled ngò gai in my ( NorCal) market.
I remember it being described somewhere as “the herb with a thousand names” or something like that, but I can’t find the source. Here’s a link to a link with names in 31 languages!
This looks useful for growing
I mostly use it for green seasoning, which I make batches of and freeze in ice cube trays.