The “Longan” is a renowned fruit of Chiang Mai and Lamphun provinces, generating income for farmers over several decades. The high demand for longan, both for export and domestic sales, has led to the heavy use of chemicals to enhance the appearance and quantity of the fruit to meet market demands. Additionally, off-season cultivation has prompted the initiation of the “Green Yield” longan project.
This project has gained recognition from government agencies, supported by the Ministry of Higher Education, Science, Research, and Innovation, and selected as a highlighted achievement by the Program Management Unit for Competitiveness . It has also received backing for practical implementation throughout the safe food chain by the Thai Health Promotion Foundation (ThaiHealth). The project has been endorsed by several experts, including Professor Chanuan Ratanawaraha, former Deputy Director-General of the Department of Agriculture and expert in sustainable agriculture, along with several specialists from ThaiHealth, to promote safe, high-nutrition products from farms to consumers.
The organic farming process has been led by Professor Dr. Puangrat Kaewlom of Chiang Mai University, in collaboration with Dr. Teerasan Boonuppara from Living Soil Co., Ltd. They have established a prototype learning area in San Pa Tong district, Chiang Mai province. The project began by gathering farmers interested in transitioning from chemical to organic farming, gradually restoring soil fertility suitable for longan cultivation by using microbial blocks to eliminate chemical residues. The results were monitored by analyzing soil, water, and produce samples for chemical residues. In addition to soil restoration, preventive measures against chemical contamination from neighboring farms were implemented using bio-extract and buffer zones. Chemical checks were conducted on the water supply, and produce was re-tested for chemicals, using various advanced technologies such as satellite, drones (UAVs), multispectral sensors, and test kits. LC/MS/MS and GC/MS tools were employed to assess the health of the produce and suggest methods for enhancing soil fertility, ensuring the absence of chemical residues and high-quality yield. As a result, the Green Yield longan has become more than just a chemical-free fruit, thanks to soil restoration and the increasing number of farmers committed to sustainable organic farming.
Currently, farmers from seven districts in the Chiang Mai-Lamphun area have formed a network under the Thai Participatory Guarantee System (PGS) organic farming model, supported by the Thai Organic Consumer Association (TOCA). Chiang Mai University and Living Soil Co., Ltd. have promoted organic farming knowledge and chemical residue testing at every stage, from the farm to the longan produce. The produce is then linked from growers to consumers, starting with the GREEN KITCHEN group, restaurant operators dedicated to selecting organic produce for cooking. This collaboration encourages consumers to enjoy safe, healthy organic longan produced in Chiang Mai and nearby areas. Farmers were invited to participate in activities promoting sales to consumers, publicizing the benefits and chemical-free nature of organic longan.
The organic longan farming initiative is part of the research and development efforts in agricultural ecosystems and carbon farming under ecological engineering. This new curriculum will be disseminated through the Multidisciplinary Research Institute and the College of Multidisciplinary Studies at Chiang Mai University, chaired by Professor Dr. Phuangrat Kaewlom. The course is being expanded from research to concrete learning and practice, supported by collaboration among government, private, and civil society sectors.
The **WANDEE Festival** aims to promote the Green Yield longan project, encouraging more organic longan cultivation and fostering organic longan trade for consumer safety. Additionally, it seeks to develop culinary tourism by linking organic longan farming sites with community-based tourism, creating new food tourism destinations and educating the public about organic longan, a well-known fruit of Chiang Mai and Lamphun provinces. The project also collaborates with Green Kitchen restaurants to create innovative longan dishes, inspiring food entrepreneurs to use organic longan in their cuisine.
This project is supported by the Tourism Authority of Thailand (Chiang Mai Office), the Thai Health Promotion Foundation (ThaiHealth), Living Soil Co., Ltd., the Faculty of Engineering at Chiang Mai University, and Rimping Supermarket, in collaboration with GREEN KITCHEN restaurant operators.
August 10
Organic Longan Community Tour: Sweet Tooth-Sweet Route
08:00 – Meet at the meeting point at Chiang Mai Cultural Center.
09:00 – Visit Thung Fa Bot Cattle Market.
10:00 – Observe traditional wood carving wisdom at Ban Kiew Lae Noi.
12:00 – Chef’s Potluck: Enjoy longan dishes by chefs from the Green Kitchen project, including Ms. Sathita Reynold from Dofann Cheese, Chef Pathapee Moonkongkaew from L’Elephant, Chef Guillaume Comparat from Shangri-La Chiang Mai, Chef Suksant Chutintrathip from Meliá Chiang Mai, and drinks from Raya Heritage.
13:00-14:30 – Chef’s Longan Story: A conversation about longan.
– Farmer’s Longan Story: The journey to premium longan by Green Yield farmers.
– Longan for Health: Disease prevention with longan, by Dr. Wimala Wiwatmongkol from Sriphat Medical Center, Chiang Mai.
– Longan selection: Techniques for choosing safe longan, with a demonstration of chemical testing in longan.
14:40-15:30 – Visit an organic longan orchard.
15:40-16:30 – Visit Doi Sap Phan Yu.
16:30 – Return.
August 12
Spreading “Sweetness” to the Community: WANDEE Festival with Green Yield Longan, in collaboration with Rimping Supermarket
Activities will be held at Rimping Supermarket, Meechok Plaza branch, providing information about organic longan. Participants and viewers of the live stream can purchase longan directly from farmers and longan-based products, with the schedule as follows:
Sweet Talk-Sweet Longan
10:00-10:30 – Exhibition: Purchase and reserve longan.
10:30-11:00 – Live Streaming: Longan talk and live sale.
– Farmer’s Longan Story: The journey to premium longan by Green Yield farmers.
11:00-12:00 – Cooking demo: Delicious dishes by Chef Dan from RedBox.
12:00-13:00 – Discussion: Sweetness with longan for health and techniques for choosing safe longan, with a demonstration of chemical testing.
13:00-14:00 – Cooking demo: Organic longan coconut pie by Chef Beer from Blackitch Artisan Kitchen.
14:00-17:00 – Exhibition: Purchase and reserve longan.
