Answer: Grass seed can take up to about three weeks to germinate depending on the variety you planted. Unfortunately, new grass is just not able to handle heavy foot traffic -- it is fragile. And this really is the most stressful time to try to start a lawn due to the heat and typically dry summer weather. The best time is late summer to early fall, so you will have a good opportunity then. You might consider using a light layer of mulch as a walking surface for the party, then reseed in early September.
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