You need Mole Mitts, and the Beetle Shop opened. First, check and see if you have atleast 200 rupees, if not, go to your house, dig to the left and you should receive a red rupee each time you go back in and out. After that, go to the beetles shop, buy the orange one, I think, and when you drink it, it should allow you to find rupees. Go to where that poem guy was where all the grass was, now, in order to do this, your gonna need the great spin attack. go to the beginning where you first see a lot of grass. Now, use your great spin attack and you should find a lot of rupees.