Answer: It's probably best to tackle one area at a time, get rid of the weeds, amend the soil and plant, then cover the bare soil with mulch to suppress new weeds and then move on to the next area. You can hand dig the weeds or you can smother them with several thicknesses of newspapers, or you can use a chemical. As you've discovered, some weed killers are non-selective and can kill all vegetation. Others are specific to grassy or broadleaf weeds. The safest thing to do is to physically remove the weeds, dig in some compost or other organic matter and then plant your flowers or vegetables. Cover over the bare soil with additional organic mulch to keep new weeds from germinating. Once you have reclaimed an area, move on to the next and repeat the process. With some hard work and diligence, you can reclaim your yard.
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