Heirloom Thursday: Thai Basil

Some of my very favorite food is Thai.  This may be different now, but there wasn't any Thai food to be found in Iowa in my youth, and the first time I ever tried it was sometime in high school.  Since then I've made up for time and consider myself something of an afficionado.  One of the characteristic tastes of Thai cuisine comes from the namesake Thai basil.

History: This basil, also called horapa in Thai, is a cultivar of the standard basil plant, Ocimum basilicum.  Whether this was intentional selection or not, it manages to retain its flavor much better than some other basils when cooked, and is thus favored for stir fries etc.  It is recognizable due to a purplish color and a hint of anise to the taste.  Some might also detect a hint of mint, which makes sense because basil is a close relative of mint.

Worldwide Production: ?? 

Growing: Plant the seeds and watch them go!  This type of basil does better in more tropical climates, of course.

Harvesting: According to the herb society of America, if you remove the top set of leaves above a node you will have a sustainable, heavy bearing basil plant. The nodes of basil don't appear to correspond to branch points but you will know the node when you see it!

Health Information: In terms of nutritional health, basil is quite good for you, like most greens. One ounce of fresh leaves has 1/3 of your daily vitamin A and a surprisingly large amount of vitamin K (145%) - those of you on coumadin, take note. Basil does contain a carcinogen, estragole, but it's effects have only been seen at levels more than 100 times higher than standard consumption.  There are no particular health claims for basil, as far as I'm aware.

References:
1. Wikipedia
2. Harvesting basil
3. Basil nutrition facts
4. Report on toxic effects of estragole (PDF)
5. Image of Thai basil from Flickr Creative Commons