Knowledge source
Indigenous knowledge
Local knowledge
Personal experimentation
Details
I took a 1-day class on permaculture from Toby Hemeway. I also have his books. I have read many other books. I have spent a lot of time in the permies.com forums and in a local home orchardists organization. I have done a lot of trial and error. A lot of my knowledge of native and invasive plants came from volunteering at a nearby wildlife refuge (1200 acres).
Knowledge timing
Details
I first started learning about permaculture in 2007.
Uptake motivation
It aligned well with my gut instincts. Also mimicking nature is always a good strategy.
Knowledge products
Rebecca Hosking's 2008 documentary "A Farm for the Future" is a beautiful introduction to permaculture: https://vimeo.com/136857929
Toby Hemenway's "Gaia's Garden" is great for people with small properties.
A huge amount of best practices can be found in the Permies.com forums https://permies.com/forums/
"Teaming with Microbes" by Jeff Lowenfels and Wayne Lewis is a great overview of what should be going on in healthy soil