The tutorials are to be as close to a live demonstration where I would paint from a live subject, not a photograph. I hardly ever paint purely from photos in my own practice. I know many tutors do, but I do not encourage students to paint only from photos as this can detract from the learning process of the techniques. Also, if you only get into the practice of painting using a photograph, you won’t ever be able to paint from life, which as a botanical artist would also be a bit restricting. We are not looking to achieve a photo-realistic finish.
Of course, if you get hold of a live subject, bring them into the studio to have alongside the project we paint together. In the support materials pack I do suggest for many of the projects, your own live subject if you can get it alongside my scanned reference images is great. Once you’ve had a go at the tutorial, you can then have a go at the live subject from your garden. Such as the wild roses you have. The colour palette will be much the same for pink ones.
I will however look into adding some additional reference photos for future projects.