Jiaogulan is a climbing vine of the family Cucurbitaceae (of the gourd or cucumber family) which grows naturally in subtropical regions in China and Southeast Asia. We discovered it at a rural tea market in Enshi, where local farmers come down from the mountains during the peak tea season, March and April, to sell their products and socialize. This Jiaogulan Tea we got from Aunt Mali, of the Tujia Ethnic Group, living in a little farm in the woods around Xuan'En County Town, near Enshi, Hubei Province. She is a most hospitable and genuine person, she invited us to visit her farm and we did it with please. She lives in a wooden hut, partly renovated, with her husband. They are cultivating a variety of tea cultivars, and make mostly herbal tea, Enshi Yulu, and Lichuan Red Tea, still the old-fashion way by roasting and frying in the wok by hand. 
Jiaogulan is a sweet tea, harvested usually in March, April and May, the leaves are tender, they are dried and then roasted on the pan briefly and stirred by hand to squeeze the juice out of them. If made like a normal green tea, either directly infusing on the cup or through the teapot at a temperature of 70 to 85  °C, it gives a charming, forest, deeply floreal, lasting flavor on the tongue, and while going down the body you feel a pleasant vibration like prolonged heat. This vine herbal tea is considered in Chinese traditional medicine, as Aunt Mali told me recently, to be refreshing against the summer heat, helpful to digestion, and energetic for your everyday life. It is also moderately calming because it does not contain theine or caffeine, which are anyway the same molecule.