Hi Aditya,

Masters courses in Horticulture are offered by the agriculture faculty different universities all over the world. The top universities according to the QS ranking are: 

Almost all universities have some kind of merit-based scholarship that they offer to their students. For e.g UC Davis has a Masters in Horticulture and Agronomy. the application deadlines for fellowship consideration for the program is 5th January 2018.

Hope this helps you.

All the best!