It refers to Don Elwood's books and the Hands of Light
Seed Company (which I doubt is still in business, even
though parts of their web page remain online).
Elwood played music to his sprouts and used foliar misting
of fertilizers, as well as used a series of subtle energy
practices.
I have updated information to share, as well as background
information to summarize.
My notes on Sonic Bloom related plant mechanisms summarize
Elwood's work and they also refer to sound-wave science in
relation to cymatics and the chaldini figures that result.
I can explain how to find archived web pages that are no
longer active, but provide access to Elwood's articles on
subtle energy.
However, right now I just don't have time to summarize the
concepts and practices and list all the resources.