Asparagus Fern (Asparagus densiflorus 'Sprengeri') leaf stems will not form roots, the only way to propagate is by division. I hope they aren't invasive in your area because they are a terrible pest plant and those little bulbous things spread and send out runners everywhere.
~ I'm an old gal who still loves playing in the dirt!
~ Playing in the dirt is my therapy ... and I'm in therapy a lot!