These are the entire reason I made the guide. The only information I could find online was wrong. After combing the map I only found the two spots where these grow, but I believe you can also get one during the quest that introduces you to alcohol alchemy. Other than the alchemy quest, the only spots I could find them was at the park in front of the hospital, and by across the street from the pigeon lady.













It grows in these to positions in the park.
1a.











1b.


2.
This location is across the street from the pigeon lady and in the dirt alley.
These were the only two growth areas that I found, but if I find more I will come back to add them. However, these of course do grow back after a certain amount of time has passed(probably a day in game, i didn't test it), and you can grind them up for seeds so you can grow them yourself in pots.

The Rocker Ivy is a little more abundant than the four leaf clover, and I did see information for these, but they were a little harder to find so I wanted to include them as well. As far as I could tell there are 4 locations to find them, however I wouldn't doubt that there could be more. They can be found growing on/next to power boxes in these 4 locations. You can also hear a buzzing coming from them as you get closer.

1.










This location is adjacent to the basketball court that is right near the location of your first camp.




2










The second location is behind the grocery store that is also a bug hideout/base, it is located on power box on the red brick building next to the store.










3.










The third location that I have found is not to far from the 2nd one next to the grocery store. It is a little bit further east on the outskirts of the construction zone area of the map.(I had picked it before I took the screenshot, so it missing the item. But that is where it grows)

4.
The 4th one I came across is across the street from the beach bug hideout/base and next to one of the pawn shops. Again I picked it before I took the screenshot.

From my own experience, all of the other items are pretty easy to spot and pretty much all over the map. In this section I'll just show you guys the top and bottom halves of my map that has a lot of the icons for all of the items filled out. Since your map already comes with a legend I won't label them, but this is for the blue mold, clown berries, yellow goo, bear garlic, flashroom, and dragonhorn items.

Top Half







Bottom Half

This is my first guide, hope it helps someone out there to be the best bum that they can be.