Garden Sized Flag

i need help choosing flowers for a small garden?

the size of the garden is 17′ by 10′ rectangle. i am going to put the American Flag on a 15′ pole in the middle and i need help choosing flowers that will look nice, are easy to maintain, and that are red, white, and blue. i live in Hardiness zone 9(Florida), the garden area will get around 4-5 hours of sun starting around 9 a.m. and is right next to the house. i do not know if the soil is well drained or what the PH level is and i do not know how to check for either. i am not a gardener but i know all of the above factors are needed to determine the plants needed. please help, no rude comments and thanks for your help.
i have not planned a design yet so i am OK with using pots or planting right in the ground. i was also thinking of spreading pebbles/stone then having a brick walk way to the pole encircling the pole 3 feet and also leading to a bench but still haven’t decided on anything. money is not a major deciding factor but cheaper is better.

You’ve probably already considered this, but thought I’d mention petunias anyway. They like full sun, can handle the heat, and are available in red, white and blue. They’ll bloom constantly all summer.

More ideas: blue forget-me-nots, blue bellflower, red poppies, white or red dianthus, white candytuft. Your local garden center may have better ideas.

I like your patriotic theme!

911 Flag Dedication in Murrells Inlet.m4v