h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

He's mentioned pretty extensively in the book called "The Botany of Desire". Sorry, I don't remember the author's name. Briefly, What Johnny did was go back to civilization in the fall to get bags of apple seeds from the apple pressing operations. He'd take them west to land he claimed (and probably cleared) on the frontier and plant them.
Apples don't breed true, the seedlings are never like the parent and are usually throwbacks in the direction of inedibility. If you want a particular kind of apple tree it has to have been grafted, which is why they're so expensive in nurseries. So Johnny'd have thousands of young apple trees, cheap but mostly worthless.
In those days, to claim a homestead you were required to plant a good number of apple trees to show you had intentions of settling in. So a hopeful settler could buy a bunch of expensive trees of known variety or a bunch of Johnny's seedlings for cheap.
So, most of the seedlings grew into trees destined for firewood, but once in a while one would have a new wonderful fruit and would be the ONLY SOURCE for scions that would bear that fruit. So having a few hundred young apple trees out in the back forty was like owning a lottery ticket, and the drawing would be when the fruit could be evaluated. If anybody wanted that kind of apple tree they'd have to come to you.
So that's why there was such an explosion of new varieties there in post colonial USA.
Wish I had the book here (it's been a few years since I read it and "loaned" it to someone). I don't remember much about the spirituality aspect of Johnny, but I do remember he did quite well financially between going out ahead of the settlers and claiming the best land he'd later sell and move on and his low cost, low quality apple trees.

Have you heard the Mescaleros (ex Joe Strummer RIP group) track Johnny Appleseed? Lyrics are here:

http://www.lyricsdir.com/joe-strummer-and-the-mescaleros-johnny-appleseed-lyrics.html

zdt

The author's name is Michael Pollan, and he's since written another incredible, life changing, paradigm shifting book called: THE OMNIVORE'S DILEMMA.

Ah yes!

http://www.michaelpollan.com/omnivore.php

You might also be interested in this guy, John Paul Flintoff; who is pretty much the UK equivalent:

http://www.flintoff.org/

zdt