Why Don’t the Developer Add a Tree?

It is interesting to read about suburban sprawls because where I live now is the best example for it. In the university village and all the surrounding districts, houses are duplicated. I am quite jealous when I drive through the district around downtown, to find that the cabins are so unique and settled along the curvy roads. A new district opposite the Ingles market tries to solve the boring duplication model by giving more colors to the façade, but to be honest, the problem is not the façade. It is the gray space, the space between public space and the private place. Most sprawls have very abrupt boundaries, the economic gardens are same shallow and small compared to the open straight car road. If we have different landscape design, they would be improved a lot. So, will any developer decide to sell a house+ a garden/ just a tree? It may pay back more. And personally, I do not hate this suburban sprawl, just a little worried for their future: will they become junk space or change into a mini urban?