0. Pick fertiliser as your soil. It's the fastest, and that's all we care about right now. We just want our plants to be mature.
1. Pick a plant you want to unlock a seed for (use a different guide in case you don't know how to do that)
2. Set up the plants required to unlock it. If it takes more than 1 plant, start with the one that takes longer to mature and add the other one so that their maturing aligns. Example: when trying to unlock Cronerice, start by planting Baker's Wheat, which takes about 5 ticks to mature, then add Thumbcorn 2 ticks later, because it takes 3 ticks to mature. This strategy is more important for plants with short life cycles, as they can often die before the whole setup is even ready if you just plant everything at once.

1. Once every plant required for mutation has matured, switch to Wood Chips, and wait for the tick timer to go down to 2-5 seconds.
2. Save the game (crtl+S)
3. Wait for the next tick
4. Check the garden: has the mutation you've been looking for appeared?
5. If the mutation has NOT appeared:
6. Reload the game (crtl+R). If that doesn't work for you, refer to the next section in the guide.
7. Repeat from the step 4 until the mutation you're looking for has appeared, then save the game and wait for the new plant to mature.

If you want to be able to quickly reload the game, go into your game folder (right click the game in your steam, click on properties, go to the "local files" section then "browse..."), then "resources" and "app" and open the "start.js" file using notepad, or any text editor you'd like (I recommend Notepad ++, it's free and trustworthy). Find this line:

if (!DEV) win.setMenu(null)

and remove the exclaimation mark from it so that it looks like this:

if (DEV) win.setMenu(null)

and save.

Here's a picture for the reference of what I mean



(This is not the only way of enabling this, and there are guides on cheating that explain how to enable console, however this way is the most comfortable IMO, because it doesn't open the console by default, and the console is big and annoying, even if you can close it... I mean, why have it open in the first place? It's not like I'm using it every time the game opens.)