If plants must be pollinated to fruit and set seed, how come my indoor herbs set seed

such as Anethum graveolens, for instance..?

 

Simon not all plants require other plants to fertilize them some are self fertile as in the case of your dill, the "anthers" (the male bit that holds the pollen) fertilizes the female "stigma" (the female receptor) a gentle movement is enough to transfer the pollen to initiate the seed developement phase.Plants that are not self fertile go to great lengths to ensure they are not and rely on spreading their pollen to other plants by bees wind etc it gives a greater diversity in the gene pool.

 

Thanks for that.