If you are wanting to visit some of mother natures best in Thailand then you should ensure that the northern region is high on your list of botanical must-sees. The provinces of Chiang Mai and Chiang Rai are renamed for having the most abundant of botanical attractions for any one area. This is a mountainous destination, but there are certainly some excellent gardens that are located city-side or beach-side for those that prefer those surrounding.
The Queen Sirikit Botanic Garden is just on the outskirts of Chiang Mai, slightly north of the Doi Suthep Temple. Here you will see 12 greenhouses, magnificent gardens and nature trails that lead to waterfalls. It sis really a great example of Thailand's biodiversity and reforestation efforts.
Doi Tung is in the Chiang Rai province, and happens to be the former home of the Thai Princess' mother. It has a Swiss affected palace that has a strangely European garden setting. On the hillside below, the Mae Fah Lung Gardens display some of the best European and tropical gardens and exhibitions. Commissioned by the Princess' Mother, this is another wonderful example of the Thai sustainable agriculture and biodiversity efforts.
Sopha Botanical Gardens at Rayong combine the pristine beaches of Thailand with a traditional garden theme. Here you can find the largest range of Thai trees and plants and there are three teak houses to marvel. A little busier, is the Nong Nooch Paradise which lays in the heart of Pattaya, one of the most famous and busiest beach locations. Here you can see Thailand's largest collection of orchids, as well as the worlds largest collection of cycads and palms. There are multiple gardens with different themes to visit as well.
Thailand's botanical gardens are a testament to their ongoing efforts to create a more biodiverse and eco-friendly environment that can be shared with horticultural enthusiasts the world over.