---
title: "Taper now?—mid-September overseed water"
description: "Taper water and clear early leaves the same week—Leaves on seed?—mid-September fork: mulch thin, bag mats, or protect seedlings Path A–C."
llmDescription: "Mid-September DIY execute fork (twelve days after Labor Day 2026 = Mon Sep 7; post–Labor Day / mid-September chapter) for cool-season fall overseed lawns that need the light-frequent → deeper handoff: Purdue AY-3 / AY-7—keep the top ~0.5–1.0 in moist with light apps often 2–4× daily until seedlings reach about 2 in, then gradually reduce frequency and water more deeply; after two or three mows shift to deep, infrequent irrigation; Missouri G6700 / G6720—keep the seedbed moist 1–2 in with light ~⅛–¼ in apps 1–4×/day until germination, continue light apps while seedlings establish, begin deepening as seedlings reach about 2 in, and move to deep-infrequent after two or three mows; Iowa State—light-frequent moisture for roughly three weeks after seeding, then deepen as plants root and treat established cool-season turf toward about 1 in per week including rain; Path A seedlings ~2 in / solid green cast → begin the taper, Path B still germinating / patchy surface film → keep the first-14-days mist plan, Path C damping-off / greasy wilt / evening disease → fix morning-first culture before deepening, Path D no seed / warm-season only → skip this seedling fork—affiliate rain gauge, hose-end timer, oscillating sprinkler, soil moisture meter, watering can, and notebook search links with tag lawnjournal0c-20—not a mature deep-soak schedule because Labor Day seed finally showed green, and not four daily floods after roots are ready to chase moisture down."
pubDate: 2026-09-12
updatedDate: 2026-09-19
topicClusters:
  - "Fall prep & establishment"
canonical: "https://lawncarejournal.app/articles/cool-season-overseed-irrigation-taper-mid-september-execute-triage/"
markdownMirror: "https://lawncarejournal.app/articles/cool-season-overseed-irrigation-taper-mid-september-execute-triage.md"
---

Twelve days after Labor Day is when many Midwest and northern cool-season yards that [cored and seeded](/articles/cool-season-aerate-overseed-labor-day-execute-triage.md) over the holiday weekend finally see a **green cast**—and when the most expensive watering mistake of September shows up: either **staying on four light floods forever** (shallow roots, soft disease beds) or **jumping overnight to a mature once-a-week soak** while bluegrass seed is still waking and rye seedlings are only an inch tall. Purdue Extension AY-3 and AY-7, Missouri Extension G6700 / G6720, and Iowa State Extension all describe the same handoff: keep the **surface film moist** with **light, frequent** water through germination, then **gradually reduce frequency and water more deeply** once seedlings reach about **2 inches**, and only after **two or three mows** treat the stand like [deep, infrequent](/articles/summer-lawn-watering-deep-infrequent.md) established turf.

This page is the **mid-September cool-season overseed irrigation-taper execute fork**—the handoff from the [first-14-days irrigation companion](/articles/cool-season-overseed-irrigation-first-14-days.md), [Labor Day aerate-then-overseed](/articles/cool-season-aerate-overseed-labor-day-execute-triage.md), [southern tall fescue highs-below-~80 °F overseed](/articles/transition-zone-tall-fescue-overseed-below-80-mid-september-execute-triage.md), [smart-controller establishment vs mature skips](/articles/cool-season-overseed-smart-controller-establishment-vs-mature-skips.md), and [first mow / traffic limits](/articles/cool-season-first-mow-after-overseed-seedling-traffic.md). It sits beside [damping-off gate](/articles/cool-season-overseed-damping-off-late-august-execute-triage.md), [germinating seed vs slime mold vs algae film](/articles/cool-season-overseed-germinating-seed-vs-slime-mold-algae-film.md), [seedling nitrogen pulse timing](/articles/cool-season-overseed-seedling-nitrogen-pulse-timing.md), [Pulse now?—mid-September seed](/articles/cool-season-seedling-nitrogen-pulse-mid-september-execute-triage.md), [mid-September henbit PRE](/articles/cool-season-winter-annual-pre-mid-september-execute-triage.md), and [mid-September broadleaf](/articles/cool-season-fall-broadleaf-mid-september-execute-triage.md) when the same polygons still need weed or feed decisions. Warm-season bermuda / zoysia neighbors that never seeded should use [fall irrigation cutback](/articles/fall-warm-season-irrigation-cutback-bermuda-zoysia.md)—not this seedling taper. This is not a remote controller program for your ZIP code. Map seedling polygons with the free [lawn area calculator](/tools/lawn-area.md) and keep leftover bag math honest with the [grass seed calculator](/tools/grass-seed.md) before you change timer minutes. Confirm with [county extension](https://www.extension.org/), rainfall, and soil texture.

## Key takeaways

- **Purdue AY-3 / AY-7:** keep the top **~0.5–1.0 inch** moist with light apps often **2–4× daily** (weather-dependent) until seedlings are about **2 inches** tall; then **gradually** reduce frequency and water **more deeply**; after the turf has been **mowed two or three times**, deep and infrequent irrigation is most effective.
- **Missouri G6700 / G6720:** keep the seedbed moist about **1–2 inches** deep with light apps (often about **⅛–¼ inch**, **1–4×/day**) until germination and while seedlings establish; as seedlings reach about **2 inches**, **gradually reduce frequency and water more deeply**; after **two or three mows**, irrigate **deeply and infrequently**.
- **Iowa State:** plan **frequent, light** moisture for roughly **three weeks after seeding**; most cool-season seed germinates in about **2–3 weeks** if the surface stays uniformly moist; once plants are rooted, established cool-season lawns commonly need about **1 inch of water per week** from rain plus irrigation during active growth—not four daily mists forever.
- **DIY mid-September job:** pick **Path A** (seedlings ~**2 in** / solid green cast → begin the taper), **Path B** (still germinating / patchy → keep the mist plan), **Path C** (damping-off / greasy / night-wet disease → fix culture first), or **Path D** (no seed / wrong chapter → skip)—not “Labor Day turned green, so copy last July’s deep soak.”

## Why this mid-September week confuses overseed water

| Cue that tempts the wrong Saturday | What extension is saying | DIY correction |
| --- | --- | --- |
| “I see green—time for 1 inch once a week” | Purdue / Missouri: deepen **gradually** after ~**2 in** seedlings; deep-infrequent waits for **2–3 mows** | Path A is a **wean**, not a cliff |
| Rye showed in five days; bluegrass has not | Species germinate on different clocks; early rye does not license a mature soak on still-dormant bluegrass seed | Keep light-frequent on slow polygons (Path B) while rye strips begin Path A |
| Southern tall fescue only seeded this week on a cool stretch | [Highs-below-~80 °F](/articles/transition-zone-tall-fescue-overseed-below-80-mid-september-execute-triage.md) seedbeds are still in the [first-14-days](/articles/cool-season-overseed-irrigation-first-14-days.md) chapter | Path B until a real green cast and ~2 in seedlings |
| Evening mister “just in case” after every hot afternoon | Long night leaf wetness stacks [Pythium](/articles/pythium-blight-cottony-blight-cool-season-lawn.md), [damping-off](/articles/cool-season-overseed-damping-off-late-august-execute-triage.md), and sticky [gray leaf spot](/articles/gray-leaf-spot-perennial-ryegrass-tall-fescue.md) weather | Morning-first; midday only when wind/heat dry the surface film |
| Smart controller WeatherSense skips already “saving water” | Establishment needs temporary light cycles; mature ET skips assume deep roots | Run [establishment vs mature skips](/articles/cool-season-overseed-smart-controller-establishment-vs-mature-skips.md) until Path A is honest |

## Side-by-side: Path A / B / C / D

| Path | What you see this week | Mid-September move |
| --- | --- | --- |
| **A — Seedlings ready → begin taper** | Labor Day / early-September seed with a **solid green cast**; many seedlings near **~2 inches** (Purdue / Missouri cue); soil surface can dry briefly between apps without white crusting seedbeds; no greasy overnight collapse | **Reduce frequency and lengthen each soak** week by week; aim roots downward; keep measuring with a [lawn rain gauge](https://www.amazon.com/s?k=lawn+rain+gauge&tag=lawnjournal0c-20); after [2–3 mows](/articles/cool-season-first-mow-after-overseed-seedling-traffic.md), shift toward deep-infrequent |
| **B — Still germinating → keep misting** | Patchy green; many seeds still ungerminated; southern / piedmont tall fescue just hit a cool window; hot wind still crusts the top **½–1 in** by mid-afternoon | Stay on the [first-14-days light-frequent plan](/articles/cool-season-overseed-irrigation-first-14-days.md); do **not** invent a mature soak because the calendar says mid-September |
| **C — Disease / soft collapse → culture first** | Seedlings melting in greasy, water-soaked patches; cottony mycelium in wet mornings; slime-mold / algae film confusion; nights stayed wet from evening mist | Triage [damping-off](/articles/cool-season-overseed-damping-off-late-august-execute-triage.md) and [seed vs slime mold vs algae](/articles/cool-season-overseed-germinating-seed-vs-slime-mold-algae-film.md); move water to **morning**; stop stacking night leaf wetness; deepen only after soft collapse stops—do not “cure” Pythium with longer evening floods |
| **D — Skip this seedling fork** | No cool-season seed this fall; warm-season lawn only; unseeded mature cool-season already on a deep-infrequent program | Warm-season → [fall irrigation cutback](/articles/fall-warm-season-irrigation-cutback-bermuda-zoysia.md); mature cool-season → [deep, infrequent watering](/articles/summer-lawn-watering-deep-infrequent.md); seed-vs-PRE readers on dense polygons stay on [mid-September henbit PRE](/articles/cool-season-winter-annual-pre-mid-september-execute-triage.md) without a mist taper |

## The mid-September overseed water-taper fork (10 steps)

1. **Confirm you actually seeded cool-season grass.** Tall fescue, Kentucky bluegrass, perennial ryegrass, and fine fescue renovation strips belong here. Bermuda / zoysia / St. Augustine / centipede without a cool-season overseed → Path D.
2. **Read seedling height and coverage—not the holiday calendar.** Purdue and Missouri both use about **2 inches** as the deepen cue. A five-day-old rye flush at ¾ inch is still Path B. A patchy Labor Day seedbed with nurse rye at 2 inches and bluegrass still waking may need **split programs** by polygon.
3. **Rule out Path C before you congratulate yourself.** Soft, greasy, collapsing seedlings in wet thatch are not a signal to water longer at dusk. Morning-first cycles, air movement, and the damping-off companion come before any taper math.
4. **If Path B:** keep the upper **~0.5–1 in** (Purdue) or moist **1–2 in** seedbed theme (Missouri) with light apps—often **1–2×/day**, up to about **3–4×** in hot wind. Measure ~**⅛–¼ in** per light cycle with a [lawn rain gauge](https://www.amazon.com/s?k=lawn+rain+gauge&tag=lawnjournal0c-20) or tuna cans. A [hose-end timer](https://www.amazon.com/s?k=hose+end+water+timer&tag=lawnjournal0c-20) helps hit morning + midday slots without guessing.
5. **If Path A execute:** drop one daily cycle at a time while **adding minutes** to the remaining soaks so weekly water does not cliff to zero. Journal seedling height, apps per day, and gauge inches. Optional [soil moisture meter](https://www.amazon.com/s?k=soil+moisture+meter+lawn&tag=lawnjournal0c-20): checks move from the surface inch toward a few inches deep as roots chase moisture.
6. **Prefer morning starts.** Light midday passes are for wind/heat that dry the surface film—not a default evening “insurance mist.” Night-wet seedlings plus sticky humidity is how Path A accidentally becomes Path C.
7. **Reprogram the controller on purpose.** Disable mature WeatherSense / ET skips that assume a deep-root budget until Path A is real; then rebuild toward deep-infrequent after early mows—see [smart-controller establishment vs mature skips](/articles/cool-season-overseed-smart-controller-establishment-vs-mature-skips.md) and [rain-sensor verification](/articles/smart-irrigation-controller-rain-sensor-verification.md).
8. **Pair water with traffic and mow gates—not a fertilizer panic.** First mow follows height and bounce-back cues in the [first-mow companion](/articles/cool-season-first-mow-after-overseed-seedling-traffic.md). Hold most broadleaf sprays until seedlings have the labeled mow count ([mid-September broadleaf execute](/articles/cool-season-fall-broadleaf-mid-september-execute-triage.md)). Seedling nitrogen waits on the [4–6 / 8–10 week pulse journal](/articles/cool-season-overseed-seedling-nitrogen-pulse-timing.md)—not a same-week winterizer dump into wet seedlings.
9. **After two or three mows:** Purdue and Missouri both hand the lawn back to **deep, infrequent** irrigation. Count rainfall toward roughly **~1 in/week** during active fall growth (Iowa State home-lawn theme), measured—not hoped.
10. **Journal the fork.** Log seed day, first green-cast date, date seedlings hit ~2 inches, apps/day before and after the taper, gauge inches, Path A/B/C/D by zone, and the date you reach deep-infrequent after early mows. Photograph the gauge in place once so next September’s timer minutes match reality.

Browse staging gear when the seedbed actually needs it: [lawn rain gauge](https://www.amazon.com/s?k=lawn+rain+gauge&tag=lawnjournal0c-20), [hose end water timer](https://www.amazon.com/s?k=hose+end+water+timer&tag=lawnjournal0c-20), [oscillating lawn sprinkler](https://www.amazon.com/s?k=oscillating+lawn+sprinkler&tag=lawnjournal0c-20), [stationary spot lawn sprinkler](https://www.amazon.com/s?k=stationary+spot+lawn+sprinkler&tag=lawnjournal0c-20), [gentle mist lawn sprinkler seed](https://www.amazon.com/s?k=gentle+mist+lawn+sprinkler+seed&tag=lawnjournal0c-20), [soil moisture meter lawn](https://www.amazon.com/s?k=soil+moisture+meter+lawn&tag=lawnjournal0c-20), [watering can garden](https://www.amazon.com/s?k=watering+can+garden&tag=lawnjournal0c-20), [lawn care notebook](https://www.amazon.com/s?k=lawn+care+notebook&tag=lawnjournal0c-20). Prefer seedling height and a moist-but-not-greasy surface over hoping mid-September invents a mature watering Saturday.

## Extension cues side by side

| Source theme | Germination / early seedling | Taper / established handoff |
| --- | --- | --- |
| Purdue AY-3 / AY-7 | Top **~0.5–1.0 in** moist; often **2–4×/day** light apps | At ~**2 in** seedling height, reduce frequency and water deeper; after **2–3 mows**, deep-infrequent |
| Missouri G6700 / G6720 | Moist **1–2 in** seedbed; light ~**⅛–¼ in** apps **1–4×/day** | At ~**2 in**, deepen and lengthen intervals; after **2–3 mows**, deep-infrequent |
| Iowa State overseed / fall care themes | Light-frequent for roughly **~3 weeks** after seeding; do not let the surface dry once seed has begun to swell | Once rooted, active cool-season growth often toward ~**1 in/week** including rain—deep, less frequent |

These are planning aids. Your county sheet, soil texture, and wind exposure still win.

## What a homeowner can still accomplish this week

**Assessment**

- Walk seeded polygons at midday: green cast vs bare crust vs greasy collapse.
- Measure one light cycle with a rain gauge; write the minutes → inches conversion in the notebook.
- Note which species showed first (rye vs fescue vs bluegrass) so you do not deepen the whole yard for the fastest germinator alone.

**If Path A**

- Cut one daily mist cycle; add duration to remaining morning/midday soaks; re-check the top inch with a finger or meter the next hot afternoon.
- Keep kids, dogs, and parties off soft seedbeds until [bounce-back / first-mow cues](/articles/cool-season-first-mow-after-overseed-seedling-traffic.md) clear.

**If Path B**

- Stay on light-frequent; stage shade cloth / light straw only where the companion pages already justify cover—not a new flood.
- Southern readers still waiting on highs below ~80 °F remain on Path B after seed day until seedlings earn Path A.

**If Path C**

- Shift water to morning; stop evening insurance mists; open the damping-off and slime-mold triage pages before buying a fungicide jug on panic.

**If Path D**

- Leave the seedling mist plan on the shelf; run the mature or warm-season water page that matches the lawn you actually grow.

## What to journal in Lawn Care Journal

- Path A / B / C / D by zone and square footage
- Seed day and first green-cast date
- Seedling height when you began the taper (~2 in cue)
- Apps per day and rain-gauge inches before vs after the wean
- Morning vs evening cycle notes and any greasy-collapse watches
- Date of first mow and date you reached deep-infrequent after 2–3 mows
- Controller program name (establishment vs mature) and the day you switched

Use the [Lawn Care Journal](https://apps.apple.com/us/app/lawn-care-journal/id1507797403) app to keep the mid-September water fork honest while seedlings harden off. Optional in-app Assistant is educational only—not an irrigation prescription for your county.

## Further reading

- [First mow now?—mid-September seed](/articles/cool-season-first-mow-after-overseed-mid-september-execute-triage.md)
- [Leaves on seed?—mid-September fork](/articles/cool-season-early-leaf-drop-overseed-mid-september-execute-triage.md)
- [Feed now?—mid-September nitrogen](/articles/cool-season-fall-nitrogen-mid-september-execute-triage.md)
- [Pulse now?—mid-September seed](/articles/cool-season-seedling-nitrogen-pulse-mid-september-execute-triage.md)
- [Drop height now?—mid-September mow](/articles/cool-season-mowing-height-drop-mid-september-execute-triage.md)

- [Last call?—northern mid-September seed](/articles/northern-cool-season-overseed-last-call-mid-september-execute-triage.md)

- [Overseed watering first 14 days](/articles/cool-season-overseed-irrigation-first-14-days.md)
- [First mow after overseed](/articles/cool-season-first-mow-after-overseed-seedling-traffic.md)
- [Aerate then seed?—Labor Day](/articles/cool-season-aerate-overseed-labor-day-execute-triage.md)
- [Aerate now?—mid-September last call](/articles/cool-season-aerate-overseed-mid-september-last-call-execute-triage.md)
- [Seed now?—southern tall fescue below ~80 °F](/articles/transition-zone-tall-fescue-overseed-below-80-mid-september-execute-triage.md)
- [Smart controller establishment vs mature skips](/articles/cool-season-overseed-smart-controller-establishment-vs-mature-skips.md)
- [Seedlings collapsing?—damping-off gate](/articles/cool-season-overseed-damping-off-late-august-execute-triage.md)
- [Germinating seed vs slime mold vs algae film](/articles/cool-season-overseed-germinating-seed-vs-slime-mold-algae-film.md)
- [Seedling nitrogen pulse timing](/articles/cool-season-overseed-seedling-nitrogen-pulse-timing.md)
- [Apply PRE now?—mid-September henbit](/articles/cool-season-winter-annual-pre-mid-september-execute-triage.md)
- [Spray now?—mid-September broadleaf](/articles/cool-season-fall-broadleaf-mid-september-execute-triage.md)
- [Seed or PRE?—Labor Day](/articles/cool-season-overseed-vs-winter-annual-pre-labor-day-execute-triage.md)
- [Seed into gray leaf spot?—Labor Day](/articles/gray-leaf-spot-labor-day-overseed-execute-triage.md)
- [Watering restrictions / variance / hand-water](/articles/cool-season-overseed-watering-restrictions-variance-hand-water.md)
- [Rain gauge / soil probe](/articles/lawn-rain-gauge-soil-probe-measure-watering.md)
- [Summer deep-infrequent watering](/articles/summer-lawn-watering-deep-infrequent.md)
- [Fall warm-season irrigation cutback](/articles/fall-warm-season-irrigation-cutback-bermuda-zoysia.md)
- [Fall overseeding timing](/articles/fall-overseeding-cool-season-lawn-timing.md)
- [Pythium blight](/articles/pythium-blight-cottony-blight-cool-season-lawn.md)

Mid-September overseed water needs a seedling-height gate—not a hope that the calendar invents deep roots the week rye first turns green.

## Sources

1. Reicher, Z., Bigelow, C., Patton, A., & Voigt, T. (Purdue Extension / University of Illinois). [Establishing Turfgrass Areas from Seed](https://www.extension.purdue.edu/extmedia/AY/AY-3-W.pdf) (AY-3-W)—irrigate often enough to keep the top **0.5 to 1.0 inch** moist (commonly **2–4 times daily** depending on weather) without saturating; once seedlings are **2 inches** high, **gradually reduce** irrigation frequency and water **more deeply**; after the turf has been **mowed two or three times**, deep and infrequent irrigation is most effective.
2. Purdue Extension. [Irrigation Practices for Homelawns](https://www.extension.purdue.edu/extmedia/AY/AY-7-W.pdf) (AY-7)—newly seeded lawns often need water **two to four times a day**; moisten about **1 to 2 inches** without saturating; when seedlings reach **2 inches**, gradually reduce frequency and water more deeply; after **two or three mows**, deep, infrequent waterings are best.
3. Fresenburg, B. (University of Missouri Extension). [Cool-Season Grasses: Lawn Establishment and Renovation](https://extension.missouri.edu/publications/g6700) (G6700)—newly seeded lawns may need **daily** water and as many as **four light waterings** in a day; keep the seedbed moist about **1–2 inches** deep (not saturated) through germination; continue light apps about **⅛–¼ inch** while seedlings establish; as seedlings reach about **2 inches**, gradually reduce frequency and water more deeply; after **two or three mows**, water deeply and infrequently.
4. University of Missouri Extension. [Home Lawn Watering Guide](https://extension.missouri.edu/publications/g6720) (G6720)—establishment chapter repeats the light-frequent → deepen-at-~2-inches → deep-infrequent-after-2–3-mows sequence; stresses light misting early and avoiding saturated, oxygen-poor seedbeds.
5. Iowa State University Extension and Outreach. [Overseeding a Lawn](https://yardandgarden.extension.iastate.edu/how-to/overseeding-lawn)—after seeding, keep the seedbed moist with **frequent, light** applications (often at least daily); late-summer / early-fall seeding windows favor cool-season establishment when moisture is managed carefully.
6. Iowa State University Extension and Outreach. [Late Summer and Fall Lawn Care](https://yardandgarden.extension.iastate.edu/how-to/late-summer-and-fall-lawn-care)—fall can be dry; turfgrass commonly needs about **1 inch of water per week** to continue active growth, with regular watering especially important for newly renovated, seeded, or sodded areas.
7. University of Maryland Extension (home-lawn seeding / watering themes summarized in regional DIY guides)—light applications on the order of about **¼ inch** per seed/sprig watering session during establishment, then wean toward deeper soaks as seedlings root—pair with local county fact sheets for soil-specific rates.

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## Topic clusters

- Fall prep & establishment

## Related guides

Cluster co-members for follow-up grounding (prefer these `.md` mirrors before scanning the full catalog).

- [Aerate now?—mid-September last call](https://lawncarejournal.app/articles/cool-season-aerate-overseed-mid-september-last-call-execute-triage.md): Mid-September DIY execute fork (twelve days after Labor Day 2026 = Mon Sep 7; post–Labor Day / mid-September chapter) for cool-season home lawns deciding whether a missed Labor Day hollow-tine weekend is still honest: I…
- [Leaves on seed?—mid-September fork](https://lawncarejournal.app/articles/cool-season-early-leaf-drop-overseed-mid-september-execute-triage.md): Mid-September DIY execute fork (twelve days after Labor Day 2026 = Mon Sep 7; early leaf-drop chapter) for cool-season home lawns deciding whether thin dry litter can be mulch-mowed into established turf or whether mats…
- [First mow now?—mid-September seed](https://lawncarejournal.app/articles/cool-season-first-mow-after-overseed-mid-september-execute-triage.md): Mid-September DIY execute fork (twelve days after Labor Day 2026 = Mon Sep 7; first-mow chapter) for cool-season home lawns deciding whether Labor Day / mid-August seedlings are ready for a first cut: Iowa State—mow new…
- [Last call?—northern mid-September seed](https://lawncarejournal.app/articles/northern-cool-season-overseed-last-call-mid-september-execute-triage.md): Mid-September DIY execute fork (twelve days after Labor Day 2026 = Mon Sep 7; post–Labor Day / mid-September chapter) for Upper Midwest and northern cool-season lawns deciding whether the fall overseed window is still o…
- [Seed now?—highs below 80°F](https://lawncarejournal.app/articles/transition-zone-tall-fescue-overseed-below-80-mid-september-execute-triage.md): Mid-September DIY execute fork (twelve days after Labor Day 2026 = Mon Sep 7) for southern transition-zone and Carolina piedmont tall fescue lawns deciding whether daytime highs have cooled enough to overseed: NC State…
- [Aerate then seed?—Labor Day](https://lawncarejournal.app/articles/cool-season-aerate-overseed-labor-day-execute-triage.md): Labor Day DIY execute fork (Labor Day 2026 = Monday Sep 7) for cool-season lawns deciding whether to run hollow-tine core aeration and overseed the same day: Iowa State—mid-August through mid-September overseed window…