You need Cracked or a Chipped Pot to evolve Sinistea into Polteageist. Here's a location guide to help you find these in Pokemon Scarlet and violet.

AUSTIN (KXAN) — Have you ever been sad about a cracked or broken pot? Especially if it’s a nice one … or an expensive or ornamental one? Gardener John Dromgoole offers up some advice on how ...

Learn how to evolve Sinistea by finding the Cracked Pot or Chipped Pot in Pokemon Scarlet and Violet.

In Pokemon Sword and Shield, you can find chipped and cracked Sinisteas. Fortunately, it isn't too difficult to tell them apart.