I've been working on designing an ornamental garden bed that blooms in yellow and purple as a mental exercise since I can't start on my yard in real life yet.
I like the idea of purple and yellow because they're contrasting colors. I don't think I want a whole yard in them, because it would prevent me from using some plants I enjoy a lot, but I'm probably going to do one bed. I've thought about colors and sizes of plants. I haven't though as much about textures as I maybe should, but I'm not good at doing that in my head.
The plants I'm thinking of using currently are:
For evergreens:
boxwood
juniper, creeping
For flowering plants:
crocus (purple and yellow)
hellebores (purple)
daffodils (yellow)
creeping phlox (purple)
tulips (purple and yellow)
violets (purple)
irises (purple, yellow and/or mixed)
alyssum (yellow)
aliums (purple)
astilbe (purple)
daylilies (yellow)
sage (purple)
liatris (purple)
black eyed susan (yellow)
echinacea (purple)
sunflowers (yellow)
This would be a sunny border near the street, so I don't want anything too large. I prefer to grow perennials because they appear and bloom for a few weeks, then something else appears, so you have a constantly changing garden. Annuals bloom for so long that the garden looks almost static and unchanging to me.
I'm wondering what sets of colors would be interesting for other areas in the yard. Red and orange? Red and purple? If I'm feeling ambitious I could design an area that changed over time - was yellow and purple in spring, for example, and then changed to red and purple in the summer.