Hi Laure, let me begin by welcoming you to Miami! I am a native and currently in my final year at the MLA program at Florida International University. Unfortunately Miami is still very young in the field of LA with a limited pallet of significant projects to be experienced along the public realm. Although South Point Park is a welcomed project by a renown professional in the field, other projects are yet to be built. We are awaiting the opening of the west 8 landscape project for the new Symphony center designed by Frank Gehry and the much anticipated Miami Arts Museum at Bicentennial Park. With that said I can lead you toward smaller scale projects beginning with Raymond Jungles Lincoln Road Plaza adjacent to the new Herzog and De Meuron parking garage and Enea Garden Lounge deigned by swiss LA Enzo Enea (http://www.eneagarden.ch/en/html/show_room/oeffnungszeiten_miami.html).
If nature and horticulture is your thing then you are at the right place: The Everglades National park, The Kampong, Fairchild Tropical Gardens, Shark Valley and if you decide to travel a bit out west you must visit Big Cypress National Preserve! Hope this gives you some insight and activities to plan for! Enjoy the Weather!