I first saw the Yod Fah mentioned in @GoDawgs thread, and since I received seeds in Nicky's swap I grew this one as part of my late winter greenhouse greens. They are different enough from the Gai Lan I grew previously that I thought I would start this thread about varieties.

The Yod Fah are vigorous large plants and continuing to produce florets for me now in June after a long stint in the late winter greenhouse. Same gorgeous large white flowers as the other one.

So these are the differences that I noticed, or seemed to, because conditions may have been (or likely were) a bit different from previous grow of a "Kai Lan" without a name.

In late winter/early spring greenhouse, when I opened the vent to a cool breeze, the Yod Fah actually wilted in the cold, while my tomato plants were ho hum about it. So they seem to be more of a heat tolerant, not cold tolerant variety.
Also I found that there is a stronger 'brassica' taste on the Yod Fah, compared to the nameless one which was entirely sweet.
And third, when I let the Yod Fah go a bit further before cutting, the stems quickly got woody, which didn't happen with the other one.

So I am wondering about Kai Lan varieties that are best adapted to cooler climate and consistently sweet and tender.
Has anyone else grown them and have any comments or recommendations?

I am still enjoying the Yod Fah which is outdoors in a tub and still making florets for me after enduring the gamut of weathers hot and cold. I intended to transplant them when spring came, but they were too large to move. Wrong timing!

I’ve grown several varieties in my effort to find the perfect Chinese broccoli. I can’t remember which one I had success with. I find it tricky to figure the right time to harvest them. A few times I made the mistake of waiting too long and they went to seed