Regalis V

The Plantworld is some planet in the Beast Machines portion of the Generation 1 continuity family.

Somewhere in space lies a planet with little to no animal life, dominated by mobile plants. Botanica's ship landed there and she and her crew took the forms its native plants to blend in and study them. Nothing else is known about the planet, even its name, so it is sometimes referred to by fans simply as the "Plantworld".

From Teletraan I: The Transformers Wiki, a Wikia wiki.