The Green Oil Factory Orb is a Green Orb which can be obtained from a Green Treasure Chest or bought on the Player Market. It gives you the ability to right click any planted Crop to make it Shiny, giving 3x the harvest of a normal crop. It has a Cooldown of 72 hours, which means you can only use it every 3 days. This effect can also be used on planted Trees, however Trees that grow randomly in the Woodcutting plots can only be made shiny with the Green Shiny Woodcutting Orb.
Shiny crops can also occur randomly if Farming Research 5 is unlocked, but the Orb is the only way to get a shiny crop at will.