Characteristics
Overview
Sunflower seeds can be found when picking wild Sunflowers.
Most of these end up forgotten at the bottom of a box. They come with the wild sunflowers you pick, as the seed's own text says, and what they grow is a flower that feeds nobody. So the question is not which planter to give them. It is whether they deserve one at all.
They earn their keep in plain dirt instead. A seed goes into open ground without a planter, and the plant that comes up is tall enough to pick out from a distance. That makes it a marker. Say you bury a small stash with a spare kit by a rock just past the treeline during a roam. Push a seed into the ground beside it, and when you come back days later, the sunflower above the grass shows you where to look.
Watch out
The marker lasts only as long as the plant. Anyone passing can pick it, it will not stand there all wipe, and a lone sunflower in an odd spot can catch someone else's eye too. Learn the landmarks around the stash as well.
If you want flowers at home, grow a few and keep a clone of a nice one. Picked, the bloom becomes a sunflower with no use.