Females bear berries, all plants produce edible asparagus, but the males are a bit heavier cropping as they don't put any energy into making berries... a few females are useful to allow you to keep a few replacement plants growing on in pots...
If you have a lot of females, collect seed from them, germinate them adn grow them on it pots for a couple of years then selectively replace the weaker females with males form the pots.