Poster's tree isn't even blooming so this won't help. Also the article explains how to improve self-pollination in a single plant.
I don't know how to make it bloom either :-) but you could try a different watering cycle, i.e., water it more (or less) frequently for a while and see if anything changes. Also try feeding it (ordinary houseplant Miracle Grow, for instance, or research what type of minerals it actually requires).
Poster's tree isn't even blooming so this won't help. Also the article explains how to improve self-pollination in a single plant.
I don't know how to make it bloom either :-) but you could try a different watering cycle, i.e., water it more (or less) frequently for a while and see if anything changes. Also try feeding it (ordinary houseplant Miracle Grow, for instance, or research what type of minerals it actually requires).