Orchid: a Drawing in Watercolor Pencil
The author of this tutorial is Tatyana Fedorova. It was made with the AKVIS Sketch plugin in Adobe Photoshop, but you can take the standalone version of Sketch. The author also used the same image ("Orchid") in her tutorial for ArtWork (creating an oil painting).
"AKVIS plugins give one a fantastic opportunity to get a phenomenal mixture of art and photography multiplied by the power of the computer and the intelligence of software. For my first experience with AKVIS I choose the AKVIS Sketch and AKVIS ArtWork plug-ins. Everything is so quick and easy. Keep up your excellent work!"