With this in mind, it may be better to aerify and overseed in early to mid-August. This will allow the established turf to heal itself prior to Poa annua germination in late September, plus it will give the new seedlings a chance to develop prior to the Poa annua germination. This should be especially effective on thin areas where Poa annua died earlier in the summer. 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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