Answer: You can kill out the grass with herbicide such as glyphosate but be sure to carefully read and follow all of the label directions including any waiting time prior to planting the area. You can also smother the lawn with newspaper topped with organic mulch, then till it in as a source of additional organic matter. When you prepare a new bed it is a shame to lose top soil along with the sod. If you can compost it, then eventually return it to the bed, that is another good method.
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