I just did a real quick search on Google on growing barley in Thailand, and this is what I found, first listing, might be something for you to check out?
http://www.ccpnorthern.com/
Remember, our barley is grown indoors, not in a large field, and not in any type of dirt, planting soil or anything like that. It's just watered, then the roots grow and suck up water and grow tall and turn green.
I know I just oversimplified that, but we're doing this on a very small scale.
Also, as for growing barley for resale, the lady that got me started in growing my barley in 22" X 11" trays is selling her barley grass as fast as she can grow it. She placed a small advert in a local Craig's list (On line local advertising) and got more calls than she could handle. If I had the room here, I would start doing the same thing. But heck, I wanted to be rich too, but THAT ain't gonna happen.
She lives way out of town in a very rural area, and she brings the turf, barley grass, into town and her customers pick it up from her one or two days a week when she is in town. If you have the space, and want to raise barley or any seed for that matter, dive in, get wet, and enjoy what you grow.
I live in the desert of North West Arizona, and we don't typically don't have grass in our front yards, but it sure makes people turn and look at me in a funny way when I say out loud, "I have to go home and water my grass."
I even brought some into town a few weeks ago to show the people at the feed store what I was doing with the Barley I bought from them. They had a great time asking me all sorts of questions (as if I was some sort of expert). At the time the particular tray I brought in was in it's eighth day of groth including the first 24 hours of bleach soak, and it stood straight and about six or seven inches tall.
I remember many MANY years ago when I had cats, and I would go to a neighborhood pet store to buy six inch square cardboard boxes with this same looking grass and take it home for my cats. I would also cut it with scissors and put it into the bird cage and the parakeets would go CRAZY with it, eating some and rolling around in what was left over when they finished eating.
As a matter of fact,
if I had a good source for small six inch square boxes I would probably give that a try, we have lots of pet stores in this area. As I recall, at that time (about twenty years ago) it was about $5 US for each small box.
Skip