Which is better, conventional asparagus or all-male hybrids?

First of all, you have to understand the difference.  Most plants have both male and female flowers, but each asparagus plant is either entirely male or entirely female, just like a person or a chicken.  The female plants are easy to see in late summer since they produce berries that turn bright orange as they ripen.

If you grow conventional asparagus, about half of your plants will be females and half will be male.  The female plants have to spend a lot of energy making fruits every year, so they tend to have fewer and smaller spears --- extension service websites say that females produce as little as a third of the food that male plants do.  That's why nurseries have developed all-male hybrids --- strains in which nearly all of the plants will be male.

The problem with all-male hybrids is the same as the problem with hybrid seeds of other garden vegetables --- you're no longer self-sufficient.  I decided I wanted to expand my asparagus planting this year, so I just dug up nine tiny plants that had self-seeded below our conventional asparagus plants and set the seedlings out in their new home.  If I wanted to get a friend started with asparagus, it would also be as simple as mailing him or her an envelope full of seeds.

Whether the lower yield of conventional asparagus is worth the ability to easily propagate your own plants will probably depend on your space constraints.  If I had less elbow room but wanted to stay self-sufficient, I might plant a conventional variety, then rip out nearly all of the female plants once I could identify them.  I would keep one female to seed new asparagus plants, still enjoying the high yields of the mostly male planting.  As it is, though, I'm too lazy to be that high tech, and am just enjoying the complex mix of all-male and conventional plants that my garden acquired over the years.