I'm in a similar situation. I used to garden back in the day and I still had all my furniture to do so on mule. I
Bought 10 Arcane Pots (they're so cheap now)
Planted vegetable seeds on darksday
Check my plants at least twice a day morning and evening (not on any particular day)
Feed dark crystal on darksday
Harvest on darksday, preferably close to full moon
I've got a total of 5 scream fungi out of three harvests. :P What gives? Can't help but feel that they've changed gardening somehow. I used to get more consistent results with it. Now I mostly just get light crystals and black rocks. >_>; Jokes on me?
Oh and here's pikko pots data:
http://ffxi.allakhazam.com/pikko/Gardening-by-Items.pdf
She apparently got fairly consistent fungi with the vegetable seed/dark crystal regardless of the type of pot used. :P
Edit: The 4 fungi per harvest is apparently untrue for arcane pots since I've got a total of 5 scream fungi. Don't be fooled :P