Tulips belong to my favorites too. Though it often draws you into wanting every petal perfect.
Keep it simple.
And lighting is key - my spotlight is a grow light. Recommended!
A grow light is a very strong light resembling sunlight a bit.
It's of course 'better' to paint in actual sunlight I think (getting the BEST shadow colors) BUT as it's grey, cold outside, this is also very great. Plus, sunlight moves. This adds a new component of difficulty, yes, not to mention when clouds move in front of the sun, etc.
Later we'll play outside!