Courtesy of Jazzo

First, I highly recommend that before doing these procedures, you have:
Level 3 soil,
Multiple Citrus Ball Cactus Seeds,
A LOT of money (10,000 at the least)
And an adventurous mind.

One thing that I love to do in every game, is discover each tier 4 flower and foliage. A quick definition of Tier 4:
A category of flowers and foliages that canNOT be bred from any other tier and must be bought or mutated into.

Each flower can be paired with a foliage. The tier 4s are paired by so IN THIS ORDER:
Arthurium Glaber
Venus Tigerfern
Tahitian Pitcher
Lilia Weeper
Baccatus Multiflora
Tilia Ridgeball.

There is an entire list of the pairs for each tier, but these are only the tier 4s. Here is the fragment of the list you will need to know:
Mela Pear Cactus - Not Tier 4
Citrus Ball Cactus - Not Tier 4
Arthurium Glaber
Venus Tigerfern
Tahitian Pitcher
Lilia Weeper
Baccatus Multiflora
Tilia Ridgeball.
We will start with a citrus ball cactus. mutation works this way:
Mutating a plant will change either the flower or foliage and will move it up or down one space on the list. Example:
Mutating a Venus Tigerfern will give you:
Venus Pitcher
Venus Glaber
Arthurium Tigerfern
or Tahitian Tigerfern.

Get it?
Good. So with a Citrus Ball cactus, we will get:
Citrus Glaber
Citrus Pear Cactus
Mela Ball Cactus,
Or Arthurium Ball Cactus.
We want Citrus Glaber or Arthurium Ball Cactus, because that moves us one step closer to Arthurium Glaber, which is the first step. If we wind up with Citrus Pear Cactus or Mela Ball Cactus, tough luck, sell it, and try again. Once you have either a Citrus Glaber or an Arthurium Ball Cactus, self-pollinate it. remember, if a plant has already been pollinated, it can never be pollinated again, even if you mutate it. Harvest the seeds, and plant one. This is the point where I get impatient and buy insta-grow. Once it's grown, mutate it. Remember the rules of mutation? This time, you want only one thing. Arthurium Glaber. If you wind up with Citrus Tigerfern or Venus Ball cactus, it doesn't matter, sell them and try again. Once you have an Arthurium Glaber, pollinate it, and plant one. Now repeat the same steps as you did with the citrus ball cactus excpt this time, you want a venus Glaber or an Arthurium Tigerfern to mutate into a Venus tigerfern. Repeat that pattern until you get a Tillia ridgeball. Save all of your seeds. This is basically the pattern:

Plant,
Mutate,
Pollinate (if you get what you want) (sell and try again if you don't)
Repeat.
You should now have the seeds for the following plants:
Arthurium Glaber
Venus Tigerfern
Tahitian Pitcher
Lilia Weeper
Baccatus Multiflora
Tilia Ridgeball.

Plant them and show off. Have a tier 4 frenzy.