make a corner garden?
check out some of these ideas:
Here is how we transformed an ugly corner: https://chemistrycachet.com/corner-into-a-cute-little-garden/
Shouldn't be that hard but it will take work and planning. First - location. Inside or out? Will it have a fence, walls or building behind it? How much sun/light does the area get? How big do you want it? How much care and water are you willing to provide it? Is it going to be flat ground or on a hill?
My rule of thumb is that the taller plants go in the back. Both for site line and support if they need it. Then reduce size as you go forward. I like to mix perennials with annuals as it adds more color and texture and I can change my color scheme year to year if I want. Place a focal point, whether it be a small tree or decoration then theme your garden around that. Be sure to take into account how large your base plants are going to get when they get full grown so that they don't crowd each other and your annual plantings out.
I have a small corner garden that is part shade and part sun. I have used a bird bath as the focal point and planted some bird and butterfly plants around the edges depending on the amount of sun they need. Then I plant small annuals between for added color. Works well, doesn't take much care and I get to watch the birds and butterflys.