This mod adds an end-game fertilizer that greatly boosts the chance of getting a giant crop (including basically guaranteeing it!). Simply apply to the middle of a 3x3 square of giant-crop eligible crops, wait for them to become full grown...

(Note: must be applied before the crops grow entirely.)

Okay....where do I get it?

Mr. Qi sells it for 5 Qi Gems each

Install

Install the latest version of SMAPI.
Download and unzip Spacecore and Json Assets, and unzip both into Stardew Valley/Mods.
Download and install AtraCore.
Download this mod and unzip it into Stardew Valley/Mods.
Run the game using SMAPI.

Uninstall
Remove every instance of the giant crop fertilizer you have in your inventory and any chest, and then remove this mod from your Mods folder.

Configuration

GiantCropChance sets the chance a crop will grow big. Note: to ensure that the crop will become giant, probably best to set this slightly above 1, which is why the default is 1.1.
AllowGiantCropsOffFarm will allow giant crops off the farm. Note that More Giant Crops will always allow giant crops off the farm, so if you have that mod installed, this configuration option will do nothing.

Compatibility

See also
Changelog

Source code

Requires SMAPI, uses Harmony.

All donation points for this mod go to Against Malaria. Please consider supporting them if you like this mod!
Looking for something else? Please consider my other mods!

Giant Crop Fertilizer