The literal translation for 青龙菜 (Cantonese: Ching Long Choy) is green dragon vegetable. I remember having this dish a few years ago. Before that, I have not heard of this vegetable at all so I wanted to find out more about it.
This led to a search on the web for more information and to my surprise, this vegetable is none other than 韭菜 (Mandarin Pinyin: Jiǔcài, Cantonese: Gau Choy). In English, the name is Chinese chives, also known as garlic chives, Oriental garlic, Chinese leek (Allium tuberosum).
I would like to add that this "ching long choy" does not taste like "gau choy" (garlic chives) at all. I like the strong taste of "gau choy" and this green dragon vegetable has none of the strong taste of garlic chives.
It is grown in Cameron Highlands by a man named Lau Kuan. There is an article in the Star newspaper dated Monday May 16, 2005 entitled "Farmer rejects pesticide use in growing chives" that explained why this green dragon vegetable does not have a strong taste like the normal garlic chives.
Below is an extract from the above article that describes the method used to grow this green dragon vegetable:
"He lets his chives grow for six weeks before chopping off the top half of the leaves to be used as mulch and fertiliser. He then
covers the remaining chives with a thick nylon netting for 10 days in a process known as blanching before harvesting them. Limiting
sunlight made the chives more tender and delicious as they contained less fibre, Lau said."
This method is a slight modification of the method used to grow yellow chives (韭黃 - Gau Wong in Cantonese). To grow yellow chives, normal garlic chives are harvested by cutting them about a few inches above the ground, leaving the roots in the ground to grow again under cover without being exposed to the sunlight at all.
You get yellow chives by covering the remaining roots totally to let them grow in complete darkness whereas by covering them with nylon nettings and letting them grow under limited sunlight, you will get this green dragon vegetable.
If you are interested to grow your own yellow chives, please refer to this blog post with the title "Growing Yellow Chives". It has photos for every step on how to grow yellow chives. Modify the method by limiting sunlight instead of total darkness to grow your own green dragon vegetable.
So after knowing all this, the green dragon vegetable is no longer a mystery to me. I hope all of you get to have a taste of this dish to see whether you like it or not.
I also found a blog post written in Chinese published on Friday June 1, 2012 entitled 金马伦 (Cameron Highlands) that has many photos of Mr Lau and his chives farm. If you are interested to see the farm and how this green dragon vegetable looked like after being packed for sale, please go and have a look, thank you.