So what is the minimum temp in Bangkok during the winter?

Looking at the weather charts, it doesn't look like the big winter monsoon over China has brought a lot of cold weather that far south and west. (Brought certain valleys in the New Territories here there first frost in four years a few weeks ago.)

My osmanthus is blooming like crazy right now.

We have no winter, just peiods of so called 'cool' days (not even weeks) scattered about from end Nov to end Jan. With cold spell temps will be around 18C in the mornings, if no cold spell then around 23/24C in the mornings. Basically not enough to induce the Osmanthus into bloom i guess.
By the way do you get the yellow/orange flowering varities of Osmanthus in HK?

That's qualifies as a winter in my book. Though the osmanthus may disagree, but I thought the osmanthus here started to bloom in the fall before we got down below 18C.

What sort of afternoon high temps do you have?

And I don't remember seeing the yellow/orange flowering osmanthus for sale at the flower market.

Do you know how easy it is to take and root Osmanthus cuttings? I don't think you can find it in northern Vietnam, but I was thinking of taking a cutting from a friend who lives in BKK and bringing it back with me. any tips? Maybe I can just buy a small plant, but customs is pretty picky about what you can bring into the country.

I am sure you can get Osmanthus in northern Vietnam, in fact I am positive you can get them there, as they are everywhere in HK and southern China. I have had no success with rooting them so far, but i know they are propagated commercial via this way. Good luck with yours

Yood

Thanks Yood, I'll look around!

Definitely everywhere in Hong Kong. And at this time of year, it's hard to miss them when they are around, especially when the gardeners plant rows of them to line walkways.