Dave Millman wrote:

I have done it two ways-bending down the stalk to bury it in the
substrate, and just waiting for the roots of the plantlets to grow on
their own on the stalk.

To clarify my previous post, the second method is to just allow the plantlets
to sprout roots on the stalk WITHOUT embedding it in the substrate-just leave
the stalk connected to the mother plant and extending up to the surface.