I have a large terrace in New York City, and am looking to fill it with some greenery without spending a fortune.  In the past I have had good luck with [morning glories](http://en.wikipedia.org/wiki/Morning_glory) in containers - they grow quickly, are very cheap of course, and have nice flowers.

However I'd like a little variety and also flowers that didn't only bloom in the morning would be nice.  I've tried [moon flowers](http://en.wikipedia.org/wiki/Ipomoea) but could never get them to bloom.

I also tried [passion flowers](http://en.wikipedia.org/wiki/Passiflora) but they did not grow that quickly, and the vines did not branch out much so there was not much volume to them.

So can anyone recommend some others?  I guess I'd prefer to plant seeds, but I'm not too picky about that.