Answer: Crabgrass is really difficult to eradicate once it is up and growing. Any chemical that will kill crabgrass will also kill your flowering plants. Hand digging is the best way to eliminate it in the summer months. Since crabgrass is an annual, it will die out when the weather cools down. At that time I would rake it out of the bed and then apply a pre-emergent in the early spring. The seeds the crabgrass left behind won't germinate and next year your flower bed should be crabgrass-free.
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