This is a small tip for you, but it might help. When painting flowers or vegetation, consider tubing up the flower to keep it blooming for an extra day or so. This is especially important if you have a flower sitting on a shelf or otherwise in limbo. Otherwise, you'll watch it die of thirst before your very eyes, often in a matter of hours, especially in the case of a fragile flower like the gardenia, above. It doesn't last very long even in the best of circumstances, though. You can get these tubes at any florists shop, I think.
I had a couple of tubes on this painting above and took them off to paint the stems when the rest of the branches were fairly dead. Every so often these gardenias defeat me, though, and I have to finish the paintings off via photos. I had to do the petals on the white flower that way; I can usually replace the flower with others from my gardenia bush, but I was flat out of flowers for a while and was strapped. For about a month, my flowers on my gardenia bush either browned within minutes after picking or fell off before blooming.
The thing I like about working this way, though, is that there was never a moment when the scene in front of me looked exactly like this, using these exact plants. It's a kind of analog - it shares motifs with other similar plants, but never quite looks like what was there at any given point. It's a synthesis of similar stems and flowers at different time periods on my shelf in front of me. Maybe it's a distillation, a condensation, of gardenia-ish-ness.
This painting is on it's way up to Abend Gallery for the 2013 Holiday Miniatures Show.