Seed has sprouted - best way to proceed?

[PSU4ME]

Hi All,
Looking to get some sequencing advice and to toss off some ideas on how to handle. Did an overseeding to about 38k (part of which was a new septic system so full seeding there) that I’m now 21 days into. Mother Nature has been really good to us and we have been able to supplement with irrigation as needed.

The sprout looked really good for elite KBG and I’m now looking to see how/if to approach next steps.

Knowing the KBG will sprout and pout, wanting input on when to fertilize. Want babies in the overdosed section to pop up for sunlight but doing so fertilizes existing grass. Should I continue to wait? Waning sunlight and incoming leaves are right around the corner and sub 50 temps in the am as well.

Second, should I do a second of tenacity? Con here is damage from driving the tractor over it to spray.

Lastly, trying to thread the needle on when to cut. Best to hold out as long as possible? I don’t think the new seed warrants it yet because of the sprout and pout but the other grass is def growing - will take any advice/experience there.

Thank you

[Smolenski7]

1. If you are 21 days in, I would fertilize. I want strong roots going into the winter.

2. I would not use Tenacity, personally. I think Tenacity is great at seeding, but I think once germination occurs, it's suggested that it not be applied until the grass has been cut a few times. It has something to do with preventing the young sprout from photosynthesizing and not being able to recover....but I could be so wrong about the reason.

3. I usually wait to cut until the vast majority of the new grass needs it. Then, I've been known to use a leaf blower to make sure the new grass stands up as straight as possible.

[PSU4ME]

Thanks for your thoughts! We are going to pick up some balanced fert today and get down a layer, will mix in some Baystate fert as well (likely to have limited life with cooler temps.)

No tenacity makes sense, might do some kelp help though.

I’ll plan to hold off on the cut and evaluate how well the fertilizer pops the young grass.

Thank you