@JohnTRN
I was able to convert the PDF to a PRC using the Windows program
MobiCreator, then I converted the PRC to EPUB and MOBI with Calibre - which I've attached
The results aren't great, eg the Compost Recipe tables didn't convert too well, but the TOC works - although its wide, so you'll probably want to 'fix' it
Good luck with the garden
BR