William's Fescue Care Guide

Tall Fescue (Festuca arundinacea)400 sq ftFairfax, VAZone 7aSod installed 2026-04-07

A year-round, science-based maintenance plan built from Virginia Tech Extension research. Every rate and amount is pre-calculated for your 400 sq ft lawn.

Day 43

Transition to Established

TRANSITION
  • Water deeply 2–3x per week (0.5 inch per session)
  • First mow when grass reaches 4+ inches — set mower to 3.5 inches
  • Use a sharp blade for initial mowings
  • Begin light regular foot traffic

Annual Cycle

Winter

Dec
Jan
Feb

Spring

Mar
Apr
May

Summer

Jun
Jul
Aug

Fall

Sep
Oct
Nov
3.5″
Mow Height
Summer (raise to shade roots)
1.5″/wk
Water
Summer (split into 3 sessions)
0.4 lbs N
Fertilizer
Per application (400 sq ft)
1.6 lbs
Overseed
Tall Fescue seed (fall)

Weeks 1–2: Critical Establishment

  • Water daily — 3x/day if temps exceed 80°F (6 AM, 11 AM, 2 PM)
  • Keep soil moist to 1 inch depth at all times
  • Do NOT mow under any circumstances
  • Minimize all foot traffic on the sod
  • No fertilizer applications yet

Weeks 3–4: Root Development

  • Reduce watering to every other day, 0.5 inch per session
  • Tug-test sod corners — look for root resistance and visible white roots
  • Still no mowing unless grass exceeds 4 inches
  • Light foot traffic OK on established edges

Weeks 4–6: First Mow

  • First mow when grass reaches 4+ inches — set mower to 3.5 inches
  • Use a sharp blade for initial mowings
  • Water deeply 2–3x per week (0.5 inch per session)
  • Begin light regular foot traffic

Weeks 6–8: Transition

  • Transition to established maintenance schedule
  • Follow seasonal calendar below for ongoing care
  • Normal foot traffic is now safe

Source: Virginia Tech Extension[VCE 418-040]

Auto-selected to the current month. Each task includes priority level and Virginia Tech Extension source.

Spring Green-Up

Watering

Transition to summer watering

Important

Increase toward 1.5 inches per week as temps rise. Deep, infrequent sessions.

Source: VCE 430 010

Mowing

Gradually raise mowing height

Important

Begin transitioning from 3″ to 3.5″ as temperatures climb. Prepare for summer height.

Source: VCE 430 523

Disease & Fungicide

Monitor for brown patch trigger

Critical

Watch nighttime lows — when they stay above 60°F for 3 consecutive nights, begin preventive fungicide.

Source: VT TURF DISEASE

Ask anything about your lawn. The AI knows about your 400 sq ft Tall Fescue in Fairfax, your sod install date, and Virginia Tech's research.

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Watering schedule by season (includes rainfall)
SeasonAmount/WeekFrequencyTiming
New Sod (Weeks 1–2)Keep moistDaily / 3x daily if >80°F6 AM, 11 AM, 2 PM
New Sod (Weeks 3–4)0.5″ per sessionEvery other day4–6 AM
Spring (Mar–May)1″ per week2 sessions4–6 AM
Summer (Jun–Aug)1.5″ per week3 sessions, every other day4–6 AM
Fall (Sep–Nov)1″ per week2 sessions4–6 AM
Winter Drought0.5″Every 3–4 weeks if no rainMidday when >40°F
TipDrought Stress Indicator

Watch for “footprinting” — when grass blades don't spring back after being stepped on and appear bluish-purple. This means water immediately.

InfoVirginia Soils

Virginia clay soils infiltrate water slowly. Smaller, more frequent applications are better than one large soak. Never water in the evening — this promotes fungal disease.

Sources:[VCE 430-010][VCE 430-520]

InfoAll Rates for 400 sq ft

Product amounts below are pre-calculated for your 400 sq ft lawn. Annual nitrogen target: 1.2–1.6 lbs N total (equivalent to 3–4 lbs N per 1,000 sq ft).

Annual fertilization schedule — focus on fall (September–November)
WhenProductN RateAmount (400 sq ft)Notes
September 1Starter 18-24-120.4 lbs N~2.2 lbs productNew sod establishment boost
October 1Balanced 10-10-100.4 lbs N~4.0 lbs productFall feeding for root growth
November 1Winterizer 32-0-100.4 lbs N~1.25 lbs productBuilds root carbohydrate reserves
April 15 (Year 2+)Slow-release 29-0-40.2 lbs N~0.7 lbs productLight spring boost (half rate only)

Application Tips

  • Use a drop spreader for uniform coverage on a small lawn
  • Apply in two perpendicular passes to prevent striping
  • Water lightly after application to move product into soil
  • Always follow soil test recommendations

Sources:[VCE 430-011][VCE 430-520]

Recommended mowing heights by season
SeasonHeightFrequencyNotes
New Sod — First Mow3.5″When grass reaches 4″+Sharp blade required. Typically weeks 4–6.
Spring (Mar–May)2.5–3.5″Every 5–7 daysNever remove more than 1/3 of blade height
Summer (Jun–Aug)3.5–4″As needed (growth slows)Taller grass shades roots, reduces heat stress
Fall (Sep–Nov)2.5–3″Every 5–7 daysActive growth returns — resume regular schedule
Last Mow (November)3″Final cutPrevents snow mold and winter matting

The 1/3 Rule

Never remove more than one-third of the grass blade height in a single mowing. Cutting more than this damages the plant, reduces root depth, and invites disease. If the grass gets too tall, bring it down gradually over multiple mowings.

Mulch clippings— don't bag them. Clippings decompose quickly and return nitrogen to the soil, reducing your fertilizer needs. Keep mower blades sharp — ragged cuts invite disease.

Source:[VCE 430-523]

Recommended fungicide products for brown patch prevention
ProductActive IngredientTypeReapply Interval
Heritage G / GenericAzoxystrobinGranular (QoI)21–28 days
Banner Maxx / GenericPropiconazoleLiquid concentrate (DMI)14–21 days
Headway GAzoxystrobin + PropiconazoleGranular combo (QoI + DMI)21–28 days
Pillar GPyraclostrobin + TriticonazoleGranular combo (QoI + DMI)21–28 days

Cultural Controls (Reduce Disease Pressure)

  • Water only in early morning (4–6 AM) — never in the evening
  • Avoid nitrogen fertilization during summer months
  • Improve air circulation — trim low-hanging branches if applicable
  • Mow at maximum recommended height to reduce canopy moisture
  • Bag clippings during active disease outbreaks

Source:[VT Turfgrass]

White Grubs (Japanese Beetle Larvae)Popillia japonica

Timing & Threshold

When: Treat late July to early August ONLY

Threshold: 10+ grubs per square foot

Treatment Products

  • Trichlorfon (Dylox) — curative, fast-acting
  • Chlorantraniliprole (GrubEx) — preventive, apply June
  • Carbaryl (Sevin) — curative alternative

Details

  • Adults emerge late June — mated females lay eggs mid-July to mid-August
  • Apply curative products 24 hours after significant rainfall when grubs are near surface
  • Larvae develop through fall, overwinter 4–8 inches deep
  • Drought in late July–August naturally reduces egg survival

Source:[VCE 2902-1101]

Fall ArmywormsSpodoptera frugiperda

Timing & Threshold

When: Monitor mid-August through mid-September

Threshold: Active chewing damage visible on new sod

Treatment Products

  • Bacillus thuringiensis (Bt) — organic option
  • Spinosad — organic option
  • Pyrethroids (bifenthrin) — conventional, fast-acting

Details

  • Tropical insects that cannot survive Virginia winters — migrate north annually
  • Identification: inverted “Y” marking on head capsule
  • Increased bird activity on lawn often signals presence
  • Minor damage typically self-resolves without treatment
  • Treat only if actively damaging new sod or critical turf areas

Source:[VCE SPES-357]

Core Aeration

Timing: September 15 – October 15

Depth: 2–3 inches

Spacing: 2–3 inches between plugs

  • Leave core plugs on surface to decompose naturally
  • Best when soil is moist but not saturated — water day before if dry
  • For 400 sq ft, a manual core aerator or rented machine works well
  • Aerate in two perpendicular passes for thorough coverage

Overseeding (400 sq ft)

Rate: 1.6 lbs of Turf-type Tall Fescue (NTEP-rated variety)

(4 lbs per 1,000 sq ft standard rate)

  1. Core aerate first to create seed-to-soil contact
  2. Broadcast 1.6 lbs of turf-type Tall Fescue seed evenly over 400 sq ft
  3. Top-dress with 1/4 inch of compost
  4. Keep seed continuously moist for 14–21 days until germination
  5. Apply straw mulch lightly if needed (roughly half a bale for 400 sq ft)
  6. Do NOT apply pre-emergent herbicide — it will prevent grass seed germination

Source:[VCE SPES-353]

Pre-Emergent (Crabgrass Prevention)

Target: Crabgrass (Digitaria spp.)

Apply: March 5–10 for Fairfax, VA

Visual cue: Apply when forsythia petals drop

Soil temp: 2-inch soil temperature reaches 55°F

Post-Emergent (Broadleaf Weeds)

Target: Broadleaf weeds (dandelion, clover, plantain)

Best timing: Fall is the most effective timing

New sod rule: Wait until after 2 full mowings before any herbicide application

Products:

  • 2,4-D based products (Weed B Gon, Trimec) — spot-treat only
InfoApplication Notes

Avoid application when air temps exceed 85°F (volatilization risk + grass stress)

Always spot-treat rather than broadcast on a 400 sq ft lawn

Source:[VCE 430-523]

Testing Details

Lab: Virginia Tech Soil Testing Lab

Frequency: Every 2–3 years

Best time: September, before fall fertilization

Ideal pH for Tall Fescue: 5.8–6.5

Tests include:

pHPhosphorus (P)Potassium (K)Calcium (Ca)Magnesium (Mg)Micronutrients

How to Sample

  1. Contact Fairfax County Office of Virginia Cooperative Extension for sampling supplies
  2. Collect soil cores from 5–10 random spots across the 400 sq ft lawn
  3. Sample to a depth of 4 inches, mix cores together in a clean bucket
  4. Submit through VCE office or directly to Virginia Tech Soil Testing Lab
  5. Results include nitrogen recommendation specific to Tall Fescue

Interpreting Results

  • Low/Medium P or K → use complete fertilizer (e.g., 10-10-10)
  • High/Very High P or K → use nitrogen-only fertilizer (e.g., 46-0-0)
  • pH below 5.8 → apply lime per soil test recommendation
  • pH above 6.5 → apply sulfur per soil test recommendation