Glass House and Orchid House, State Botanical Garden, Nandankanan

The State Botanical Garden at Nandankanan was conceived together with the neighbouring zoo. According to the history published by Nandankanan, Odisha forest officials first thought of showing rare animals and orchids typical of the state in the Odisha pavilion at the World Agricultural Fair in Delhi in 1960. The zoo, inaugurated on 29 December 1960, was placed in the Jujhagarh forest block; the botanical garden was planned for the Krushnanagar block, with a flower garden and medicinal plants of Odisha. It came into being in 1963 under the Horticulture Department, and its management passed to Nandankanan on 1 August 2006.

The Orchid House: in February 2010 the New Indian Express described it as built for 37 lakh rupees (3.7 million) from the State Plan Fund and awaiting opening, the zoo having sought the technical help of an orchid specialist for its design. Odisha's Chief Minister, Naveen Patnaik, inaugurated it as part of the zoo's golden jubilee celebrations, and The Telegraph shows it open in August 2010, with hybrids only, pending sections devoted to the state's own species.

The garden later added a butterfly park opened in February 2014, its interpretation centre (March 2015) and a carnivorous plant garden (March 2016).

The official page presents the Glass House as a 'spacious glass house' of 2,013 square feet, about 187 m², developed for succulent plants. The 0.65-acre Dry Garden, laid out with loose stonework to give the look of an arid zone, lies in front of it, and the Hibiscus Garden sits between it and the Palm Garden. The Cacti House, of 1,080 square feet (about 100 m²), is the only house the text calls a polyhouse; the Green House, described as 'state of art', measures 5,200 square feet (about 483 m²).

The Orchid House covers 5,000 square feet (about 465 m²). According to the New Indian Express in 2010 it was fitted with arrangements for aeration, water sprinkling and misting, and the zoo drew on the technical assistance of the orchid expert Sarat Chandra Mishra for its conception and design.

The Glass House shelters succulent plants, and the official page notes ornamental plants in bloom from November to March. The Cacti House holds more than 1,200 cacti; the Philodendron House more than 2,000 plants of five varieties; the Green House cultivars of 60 indoor species, including Aglaonema, Calathea, Monstera and Dieffenbachia. The garden also keeps more than 300 bonsai of 55 varieties.

The Orchid House, billed as the largest in the state, now displays more than 1,000 orchids of 57 varieties belonging to 37 species, in bloom all year according to the garden. Figures vary between sources: in February 2010 the New Indian Express announced 156 varieties of 35 species for about 1,000 plants, and the inauguration report gave 1,050 plants of 154 varieties, including the national flower of Panama. Odisha has 132 recorded orchid species, of which only 29 were on show at the time; the zoo announced a future section for the state's own orchids.

The garden covers 75 hectares in the heart of the Nandankanan sanctuary, between two wetlands, and groups 24 satellite gardens over undulating ground: the display houses form only part of it. It charges an entry fee separate from the zoo's. Around the Glass House lie the Dry Garden, in front of it, and the Hibiscus Garden, between it and the Palm Garden.

The ornamental plants of the Glass House bloom from November to March, the season when the rose garden and the Mughal garden are also busiest according to the garden. The butterfly park (2014), the carnivorous plant garden (2016) and the neighbouring zoo round off the visit. The site lies in an eco-sensitive zone of the sanctuary, and meetings with high-decibel sound are not allowed.