I'm all about angles when it comes to photography. I love getting down and shooting up, or taking my iPhone and holding it beneath my subject - sunflare optional but almost always fabulous.
Yesterday at Floriade, people gave me endless queer looks as I snuck my phone underneath a hazy bed of poppies and snap, snap, snapped. Just look at the results (above).
I prefer natural light when I shoot, but flash illumination on the brightest of days is also a trick I've learned. Although I didn't do it for the flowers above, it works really well on solid objects (the use of flash on the petals would have dulled the opacity of the petals). Just turn the flash on when taking pics in direct sunlight--it will add an illuminating freshness to your subject matter, especially if the object is well-illuminated but actually out of direct sunlight.
All of the following photos were taken shooting UP, with no flash and with my iPhone 4S. No filter has been applied, though I have lightened the midtones by 10%, just to give that extra pop of light.
You can also shoot into the sun with the subject in shade, rather than direct light, as seen by the two pictures below. This gives a lovely silhouetted effect, with less saturated colour and more depth. You could also add flash to these images for a cartoon-like popping effect.
Not flowers - but feathers. These belonged to two beautiful girls on stilts, wandering the Floriade grounds. The image on the right caught a little too much haze from the sun, so it has had its contrast levels adjusted. You can see how this has given the sky a more saturated blue.
And here are the girls, in all their splendour.