I am really bad about finding plants and buying them in numbers of 3. Why 3 I don't know as I am an "even and balance it out" type of person. Once getting the plants from the Garden Center and to my Georgia home, I have no idea where some will end up.
I made two identical planters along the pathway of the garden separating a higher level of the garden to a lower level of the garden. I will talk more about the garden levels another time. Here I have highlighted the two planters for you to see where they are located.
Now lets move in for a closer look at the two planters from their start.
I made the planters with scalloped, curved border stones that once were used as borders elsewhere in the yard. They are now planters! The pea gravel is the pathway below. I came home with 3 Blue Daze plants and 6 Wave Petunias. Hey, I got the Petunias in an even amount even though I only needed 4 of them. I also had 2 Red Star plants (Cordyline Australis) and some white Alyssum seed.
Of course the center holds the Red Star and the Daze was placed in front of it to flow over the 3 inch wall. Two Petunias were placed on either side of the Daze and the Allyssum seed was scattered within the Petunia and Daze.
In a matter of weeks, the Daze and Petunia were blooming as well as the white Allyssum.
Both planters are now so full that you can no longer see the brick border of the planter.
The colors all work well with each other making for a beautiful Pink, Blue and White planter. If only the Blue Daze were not a morning bloomer and would stay open all day long. Arggg....
Now what did I do with the remaining odd ball blue Daze and Petunia you ask? Well, put them in a pot of course! This entailed another trip to the garden center for a Spike plant for the center of the pot. I had the large pot collecting dust in the shed so I did not have to buy that item on this trip.
Just as the other planters, I put the Blue Daze to the front of the centered Spike plant with the wave Petunia on either side of the daze. To my surprise a Hyacinth bean was in the pot so a vine grew in time. I just love surprises!
This pot is on the opposite side of the garden so it kind of encloses the garden with color at this end and ties the colors in with the other side of the garden. 
If you find yourself buying things in odd numbers like three, do like me and make TWO PLANTERS AND A POT, In the Garden...