If you have violets next spring, apply the same product in late April, early May. If crabgrass continues to be a problem, try a pre-emergence herbicide in the spring, but I would apply only to the trouble spots that you have had in the past. That way you save money and reduce needless pesticide use. The information given herein is supplied with the understanding that no discrimination is intended and no endorsement by the Purdue University Cooperative Extension Service is implied. Any person using products listed assumes full responsibility for their use in accordance with current direction of the manufacturer.
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