How can you get more garden beds in the dreamworld?

Question

I've seen people with 3 or more garden beds but you can't buy it with the dream catalogue so how can you get more?

Answer 1

"Two rows [of berries] are available from the beginning for players to plant their berries in, with each row allowing players to plant up to three Berries. A third row will be dug by Diglett after players have earned at least 900 Dream Points, and a fourth after they've earned at least 2100."

http://bulbapedia.bulbagarden.net/wiki/Dream_World