There's so many ways to start a painting. Some artists like to "tone" their canvas with a neutral color in a midtone value. Some artists tone their canvas with the complimentary color of their scene or painting. I tried something different and worked just on the white surface. It's worth trying again.
I Looked for the Shadow Patterns in my composition. I Painted them instead of the shapes of the flowers and leaves. This way I could see where my eye would travel in the painting and whether or not I liked the composition.
Step One: Shadow Patterns
Next, I added in the midtones trying to pay attention to temperature as well as value.
Step two: Shadows and Temperature
Step three: Filling in positive shapes, paying attention to brush edges
Finally, I added in the rest of the painting being sure to soften edges where there wasn't a big value change and crisp up edges catching light.
I tried to simplify the little carnation type flowers in the bottom right. not sure if that's been resolved yet. But, there you have it, a painting may never be finished, right?
Don't stay stuck too long in any painting. Move on for awhile if you've hit a wall, then come back to it with new fresh eyes and ask for help and feedback from other people.