After blocking out, it’s a case of gradual refinement. The biggest benefit to using a 3D program in this way is that, for the most part, the image is editable right up until the end. Increasingly, I find myself using particle systems less and less, opting to place everything individually, as there is really no beating a deliberate hand.
Lighting & Rendering
I try to keep my lighting set-ups as simple as possible, as render times can run long quite quickly. Typically, by the time I’m getting close to moving into Photoshop for colouring, the render times are around 5-10 minutes, which doesn’t sound like a lot, but I’m re-rendering constantly as I move things around. I’ve automated the process within Blender as much as I can so that when a render completes, I get a folder of images with the light, depth, and individual mattes for coloured items. That way, I can link them in Photoshop so that even if I move a plant to the other side of the composition, everything updates without my input.