That's a good question. Staminate flowers do
indeed only have male reproductive organs.
However, they can occur simultaneously on plants
with pistillate flowers, which are their
female counterpart. Examples of such plants
are squash, corn, and begonias.
Alternatively, some species have the staminate
and pistillate flowers on different plants.
Examples include asparagus, spinach and
cottonwood. Regardless of whether they occur
on the same plant or on different plants, the
flowers are in close enough proximity that
fertilization can occur.
I hope that helps!