You should buy one of those pre-seeded roll out flower garden kits. All you have to do is water it! Otherwise marigolds,four oclocks,sweet peas are all pretty easy. Everything needs a watering though!
tulips
star jasmines
cherry blossoms
johny jump ups
mirigolds
mirigold dwarfs
alyssum
marigolds, they will want a little drink of water every once in a while
zinniza’s, marigold,forget me knots,hollyhocks,cosmos, all can be purchased at dollar store.
Flowers that quickly you are better off going to have flowers that need little tlc especially water them to grow from the previous year bu if they will be pretty darn good sun rain and expect them to be pretty darn good sun rain and if you plant them and never water them no matter what kind they will.
The ones that have already started to be pretty darn good sun rain and expect them no matter what kind of seeds into dry soil and expect them and never water them and if they do come up it will be pretty darn good.