As a dilatory practice there is perhaps nothing quite so satisfyingly useless as painting a vase of flowers, the facsimile is never as attractive as the original but still anything in a vase sets up a puzzle that there is pleasure in working through. Here the question is overlaps, and one thing about drawing , as you can see here, where two stems, two leaves and a petal overlap in the sketch but the first in line gets the paint, is you can write in the back story, though this is the messy kind of mistake which no-one sensible would aspire to.  You might not be surprised to hear there is a series of flowers - though I started off spelling that flawers - in vases.  Would the collection noun for that be an in-vasion ?