I'm fortunate to have several nice clumps of pink lady slippers (a ground orchid) at the sanctuary:
It's rather rare that these flowers set seed, about 1% of the time. Here's a description of the finicky pollination process taken from this excellent website.
"Pollination in lady's slippers involves deception and entrapment! It's pretty much the same process in all species of lady's slippers. The flowers have little or no nectar to reward insects, but their bright colours are attractive. The shape of the slipper part of the flower (the lip) encourages insects, usually bees, flies or beetles, to crawl inside. They enter through the fissure in the front of the lip, then find that they cannot exit the way they entered, owing to the infolded margins. The inside of the lip is designed to guide the insect to the only exit, out the base of the lip, where it must pass by the flower's stigma, depositing any pollen the insect may have been carrying. Then as it leaves the opening in the lip it brushes past the anthers, collecting more pollen, which hopefully (from the plant's perspective), will be carried to another lady's slipper of the same species."
If one is lucky seed pods may form in the fall. When these split open they release the tiny seeds, which are like dust, or even smoke. I monitor seed pod formation (I usually only get 1, 2 or 3 per year), and when the pod is perfectly ripe and about to split, I remove it, and split it open manually in locations where I think they might "take". Absolutely vital for germination and growth is a symbiotic fungus, which is only present in acidic forest floor duff, for example under mixed oak-jack pine woods (which I have along the western edge of my property). I try to do this on a windless day, and release the "smoke" very close to the ground. This procedure has been successful - I now have lady slippers popping up all along the woodland trail. Unfortunately the abundant deer sometimes browse both leaves and flowers, so my population is only slowly expanding.
From the description of pollination given above it should be clear that lady slippers are NOT a hummingbird plant. But they are very pretty.