Listen to the Drunk Fish

If you talk to Jogu the Drunk he will forecast which crop will have the highest yield for the next day. Depending upon your standing he will charge anywhere from 25g (stranger) to free (best friend). If you plant the crop he suggests, you will receive an increase yield as well as an increased chance at the rarer items you can get from farming. To get the achievement, obviously all you need to do it plant what he forecasts until you've gotten all of them.

Ask [npc=58710] about tomorrow's crops and plant one seed, depending on what he say.

Green Cabbage = "Oooh... ooooh! My senses are tingling! I see... huge Green Cabbages in your future."
Juicycrunch Carrot = "You ever heard of a juicycrunch carrot? They'll never be juicier than tomorrow."
Mogu Pumpkin = "Pumpkins! It'sh gonna be huge, gigantic pumpkins!"
Pink Turnip = "I'm seeing Pink Turnipsh in your future."
Red Blossom Leek = "Shpring for a leek, and you might get two."
Scallions = "Have I ever told you that I hate Scallions? Hate 'em! <Jogu lets out a loud belch.> Unfortunately for me, they're going to be in high season tomorrow."
White Turnip = "Fields of white turnips. Raw and shipicy!"

FYI for those wondering the specific time:

A bountiful day, which will only apply after daily quests reset, will give you seven instead, and a Plump crop will give you eight. Also, harvesting a crop always has a 50% of producing 1-3 seeds of that crop, and there is a rare chance to get a Tiller gift (see Known members further down). There is also the chance that your seed will immediately grow into a Bursting plant, which can be harvested right away and can give the amounts of a bountiful day