Instructions
Go to Viridian Forest. Bring a Pokemon that knows the move Headbutt.
Use Headbutt on random trees. Sometimes Seedot will fall from the branches.
Explore the Meadow section of the Safari Zone. Walk through the grass on the plains, and you may encounter a Seedot. Throw Safari Balls at Seedot to capture it.
Import a Seedot from the Game Boy Advance games "Pokemon Ruby" or "Pokemon Emerald" using the "Migrate From" option on the main menu. After importing Seedot, visit Fuchsia City's Pal Park to recover your new Pokemon.