Choosing Thai mangoes at a market in Chiang Mai, Thailand. The season for Thailand's mangoes is around April to June. While the month of April ushers in the sometimes oppressive heat and humidity of the Thai hot season, one compensation is that it is the beginning of the Thai mango season. Ripe mangoes are eaten for dessert while pickles and chutney are prepared from unripe fruit. Thailand's tropical climate is perfect for high quality and abundant mango growth. When the country's tropical heat reaches its height in April and May, the mangoes ripen. The tree is an evergreen, although it only bears fruit once a year. The Thai people are very fond of mangoes, both green and ripe for an anytime snack. They like to thinly slice the green fruit and dip the crisp slices into fish sauce or in a mixture of sugar and chili powder known as mamuang naam pla warn. There is also yaam mamuang, which is a spicy with shredded unripe mangoes.