they're flowers right?
I've not done much flower-photoing (as you may guess, they're not a subject I'm strong on!), but I suppose your approach would depend partly on where they are...
If it's windy, you'll probably want to get a good fast shutter speed to minimise any motion blur (although you might get a cool abstract with a long shutter speed), so I'd use flash. A wide aperture would reduce your depth of field, but would also speed your shot up a bit if you need to.
Some water droplets often help to make the shot more interesting - if it's not already wet, you could take a small spray bottle? you'll need a dedicated macro to get really close, but you won't need one to get a good shot. Anyway, these are just a few general thoughts, I'm sure other people will be able to provide more specific advice
Zan