How do you unlock evil chao garden

By making sure that it is Evil give it 3 to five dark fruits from the market....they are mostly green at the bottom reaching up but the colour at the top is a greyish black colour also pet with only the three main dark charatures shadow,Eggman,rougeter after few hours it will elvove then run out of the main first chao garden exit....At your left you will see rainbow stairs going down.