No steak plants for me?!

[Heilena]

The trigger for the omni quest is the opportunity that goes something like "bring 20 excellent produce to the restuarant for an opportunity to grow some interesting things"... I can't recall the exact wordage but this is close.  Soon after I completed that opp, and right when 2 of my Sim reached level 8, they got the quest.  I have a third that didn't get the quest and I am thinking that its because she basically read her way through gardening.

[Blue Rage]

My sim always got these opportunities while tending their garden, specifically the non-life/flame/death fruit parts.

[Gastfyr]

You might want to try this mod: http://www.modthesims.info/download.php?t=351390  It helps, and to me anyway, it doesn't seem like cheating.

I actaully edited the XML of this one myself after downloading it, becuase I felt it made the opportunities a bit too frequent.  I think I changed the frequency to 0-2 days.  Default game is every 2 to 4 days, and the mod I liked changes it to every 0 to 1 day.  Once you figure out what you're doing, hacking XML is pretty easy, so you can change it to anything you want to suit your own playstyle.