After you have talked to Gaeus you can now start this Event. Go out the front door of your house and take the path to the Lower Left.
Defeat the four Lullabuds and Trent will grow out of the ground. Trent is a tree that can grow Produce from seeds that you give him.
Talk to Trent to give him some seeds. In order to complete this Event you need to wait a few game days until Trent has fully grown some Produce. Wait until the Produce is ripe, stand underneath the item you want to pick, and press X to pick it. Put the Produce in the big wooded box to end this simple Event.
Note: You need to wait a few Game Day's before produce will ripen. To speed up this process, just go to the World Map and keep running back and forth(move your character to different lands). Every land that you cross causes one day to pass.
This event is miss-able in the cactus diaries! Return home, talk to Lil' Cactus, go downstairs (watch him write the Event on the leaf), and go back upstairs to save your game before continuing.