I think you didn't get a response because it's a very broad question.
When you say dream garden a whole bunch of different and contradictory images come in my head:
there's the cozy enclosed space with lots of flowers and vines and hanging baskets, a reading nook, a fire pit and water feature...
there's the sunny open space full of meadow flowers, buzzing with bees and butterflies
there's the nice flat fenced in spot to grow veggies with neat garden beds.
all of those are dream gardens!