ISO idiot-proof flowers for my balcony

[ny biker]

Now that spring is here (despite the freezing temps we expect overnight tonight :(), I'd like to brighten up my balcony with some colorful flowers. What kind of flowers/plants are good for a south-facing balcony that gets lots of sun? I need something that's easy to take care of and really hard to kill, because the only thing I know about gardening is that I'm not good at it.

Thanks!

p.s climate is mid-atlantic US - hot and humid in the summertime.

[GLC1968]

Petunas or marigolds...I always have the best luck with them because I generally suck at watering and they don't seem to care too much. They like lots of sun, too.

Impatiens or begonias are great if it's more shady.

[Eden]

Marigolds are about as bomb proof as flowers get. Geraniums are pretty easy too. I love petunias for hanging baskets, but they do frizzle pretty easily if you forget to water....

[tulip]

Zinnias and sweet potato vine are nice choices. Or a big pot of lavender. In fact, herbs would be great because then you can also use them for cooking. Rosemary, sage, thyme (parsley prefers cooler temps, despite Simon and Garfunkel's grouping them all together), oregano, basil...those are the basics.

[Eden]

That's a great idea! - lavender, rosemary and sage are all very heat, drought and neglect tolerant.

[tulip]

Keep in mind that no plant will live on total neglect. Potted plants require watering more often than those in the ground because the pots heat up. Plastic pots will retain moisture better than terra cotta, but I prefer the look of terra cotta pots. Glazed terra cotta retain moisture better than unglazed, but not as well as plastic. Be aware that black pots will really heat up and might not be such a good choice on a hot balcony. Bigger pots retain more water for longer than smaller pots (an obvious but often overlooked consideration).

Gaura is also a nice plant for pots, as are ornamental grasses.