The 170 rai of land in Mae Suai district of the mountainous province of Chiang Rai has been an experimental ground for a former top-ranking official pursuing an interest in herbal wines.
Yongyuth Sarasombat is a former PM's Office Minister. Now, the occupation on his name card reads: Winemaker.
Mr Yongyuth runs a multi-million-baht wine business with a herbal twist.
His farm is famous for a long list of herbal products, including wine.
"I hadn't thought of producing a herbal wine on an industrial scale like this before. From the start, I made the wine for my friends and I to drink," he said.
"Honestly, I never thought of turning it into a business."
One day, former finance minister Virabongsa Ramangkura paid him a visit and showed him how fresh santol and mangosteen, available in abundance on his farm, could be processed into herbal wine.
Assured by Mr Virabongsa that the products would sell very well, Mr Yongyuth concocted a alcohol-free herbal and fruit wine which he makes to this day.
Most of the wine is exported to Asian markets under the La Sante brand.
The wine is the product of fruits harvested on his farm, where a wide variety of rare breeds of farm crops are also grown.
On his 170 rai farm, 70 rai is filled with purple rice fields.
His sang yod rice, a strain native to Phatthalung, makes 5 million baht in revenue a year. The corn farm and the mixed orchard of santol, longan, rambutan, long kong (Lansium domesticum Corr.), coconut, mangosteen, and other types of fruits are also doing well.
The herbal plants used for producing various types of herbal medicines have grown there since 2001, well before Mr Yongyuth's retirement from the civil service. The plants include lingzhi mushroom, pool khao (Houttuynia cordata Thunb.), jiaogulan (Gynostemma pentaphyllum), ringworm bush (Cassia alata ( L.) Roxb.), mak mao (Antidesma velutinosum Blume), clove, jatemulploeng (Plumbago zeylanica L.), and roselle.
Before his retirement, Mr Yongyuth spent a portion of his inheritance buying the first 32 rai of the land. He fell in love with the lush green expanse of the fields on a working trip there in 1989.
After that, he managed to get his siblings to pool more money to buy more land and expanded the property.
After the first plants took root, there was no turning back for Mr Yongyuth.
"Before I decided to buy this land, I brought a feng shui master over here to inspect it. He approved of it because the back of the land is adjacent to mountains and the Lao River runs in front of it," he said.
At the time he bought the first tract of land, Mr Yongyuth was a deputy cabinet secretary-general. The land was not expensive then.
The land was left idle until more plots were purchased and added later.
"At the time, I thought only of spending my retirement in peace and quiet here. But as it turned out, we kept acquiring more and more land and decided to try our hand at running a business," Mr Yongyuth said.
"We're a family of doctors. My children are also medical doctors and so are most of our friends and associates," said Mr Yongyuth.
It was in the company of medical professionals that his passion to produce health products heightened.
After extensive discussions with medical friends whose work involved herbal plant research, Mr Yongyuth began his own research on some herbal medicines with immunity boosting and hormone replenishment properties.
He has set up a foundation to offer herbal medicines made from khao tong (Houttuynia cordata Thunb.) free of charge to patients with chronic diseases such as HIV/Aids.
All the herbal plants grown and used in the production of herbal medicines at the farm are free of pesticides and insecticides.
In addition to the production of herbal medicine and food supplement products, he has envisaged building an "organic health park," a holistic health resort nestled in the northern natural surroundings which should appeal to tourists.
Organic food and drinks, and natural health care and healing services will be offered at the resort.
One part of the resort has been completed and developed into a hot spring facility.
But the project needs more investment before it can get up and running and Mr Yongyuth has been in talks with potential foreign partners, including some from Japan.
He said he wants the project to be a joint venture to help lighten the financial burden. He is still in the red from the farm and wine business although he hopes to break even next year.
"When I was a salary man, I was paid regularly every month. But when I turned to running my own business, I've been having to invest and take care of everything on my own. So, I'd rather go slowly," he said.
But he has shown no sign of slowing down yet.
Mr Yongyuth still works seven days a week, three days in the North taking care of the farm and the rest of the week in Bangkok overseeing business transactions.
Business occupies most of his time. But he does find some spare time to give lectures at universities.
"Many people warned me that if I didn't keep busy after retirement, my brain could degenerate. So I have to find something to do," he said.
"The tip is to avoid stress as we keep busy as that will make us age quickly.
"Prioritise your tasks well and you will have a happy working life," he advised.
Mr Yongyuth is no stranger to academia, having graduated with degrees in dentistry and law. He also undertook further study to gain entry to the Bar while obtaining a master's degree in hospital management from the University of Alabama and a doctorate from Johns Hopkins University.
Mr Yongyuth started out working in the civil service at the Police General Hospital and later moved to the Public Health Ministry and the PM's Office.
At the PM's Office, he served as secretary-general of the traffic system management committee for nine years.
His last and most senior position was permanent secretary.
At the PM's Office, he introduced staggered working hours for commercial banks and government offices, which helped alleviate rush-hour traffic congestion.
Mr Yongyuth is married with three children - two sons and a daughter.