Answer: You'll want to remove the grass and amend the soil prior to planting your edible landscape. You can rototill and rake or you can use a vegetation killer then rototill. Either way, you can begin planting in late summer and early fall. The following publication will give you some ideas on how to design and space your new plants: http://ohioline.osu.edu/hyg-fact/1000/1255.html
Hope it gives you some great ideas!
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