Answer: Weed barrier will block sunlight, which will keep weed seeds from germinating. Properly installed, it effectively keeps flower beds weed free. If you decide against weed barrier, you can pull existing weeds and then use a pre-emergent herbicide such as Preen. It is safe to use in perennial beds and will keep weeds at bay for quite a long time. Be sure to apply according to label directions.
Best wishes with your flower gardens.
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