How to Make a PlantSim on The Sims 3

By Science

Create a regular Sim. Unless you already have a single Sim, create a new one.

Get a Sim to level seven in the Gardening skill. Reaching level seven unlocks the ability to plant special seeds such as the Forbidden Fruit seed which is required in order to turn your Sim into a PlantSim.

Obtain seeds of any kind to later experiment on and put them in your Sim's inventory. Seeds will randomly appear in the garden as the garden is tended to. Seeds can also be found in parks.

Perform gene-splicing experiments on the seeds on a ZRX-9000 Science Research Station until you gain a Forbidding Fruit seed.

Plant the Forbidden Fruit seed and let it grow fully.

When the plant is fully grown, either tend the garden on the plant or harvest the fruit. To transform an existing Sim into a PlantSim, eat a Forbidden Fruit. To increase the chances of getting the fruit use the Tend Garden option on the Forbidden Fruit plant. After eating the fruit, wait for the "Botanitis Minorus" moodlet to expire. To force the Forbidden Fruit plant to produce a PlantSim baby, use the Harvest option instead. This creates a new baby PlantSim to create a new family member.

By Romance

Create a regular Sim. Unless you already have a single Sim, create a new one.

Move somewhere into the neighborhood. Afterwards, head to the sorority in the University.

Go into the sorority and find a PlantSim called Sharon. If you are playing as a girl, look for Shea. Build your friendship with either one of them.

Get romantic. Once you have had a first kiss, they can become your lover, fiancée, or spouse. Shea and Sharon don't have homes so you must get them to move in out of University and into your home world with your Sim, as it is not possible to Try for Baby with a Sim in University.

"Try For Baby" with the PlantSim. PlantSims can't get pregnant, but can still Try for Baby anyways, and doing this will make the PlantSim generate a "Forbidden Fruit Seed", which can then be planted. (To get a seed, do a science experiment or have a PlantSim try for baby.)

Plant the Forbidden Fruit Seed. The Sim must have level seven in Gardening to plant the seed. When you plant it, there is a 50% chance you will have a regular fruit or produce a PlantSim baby. Eating the fruit is required to transform an existing Sim into a PlantSim. To increase the chances of getting the fruit, use the Tend Garden option on the Forbidden Fruit plant. To force the Forbidden Fruit plant to produce a PlantSim baby, use the Harvest option instead. Once this is done, you now have a PlantSim.