Lawn Care Guide for San Mateo County

San Mateo County, California

Data Story

About Lawn Care in San Mateo County, California

Prime conditions for a lush lawn

San Mateo County boasts a lawn difficulty score of 70.1, making it significantly easier to maintain turf here than the national median of 50.0. The mild climate in USDA Hardiness Zone 10a provides a stable environment for consistent growth. You face fewer hurdles than most California residents, as the state average score is only 51.3.

Stable coastal weather minimizes stress

With only 14 extreme heat days per year, your grass avoids the scorched-earth conditions common in inland California. The 25.4 inches of annual precipitation falls just under the ideal 30-50 inch range, requiring moderate supplemental irrigation. You benefit from 2,921 growing degree days, ensuring a steady but manageable growing pace.

Preparing your soil for success

While specific county-wide soil data is limited, local coastal terrains often require testing for salt content and drainage capacity. Adding organic compost can improve moisture retention to compensate for the 25.4 inches of annual rain. Aim for a neutral pH between 6.0 and 7.0 to ensure your grass can actually absorb the nutrients you provide.

Resilient landscapes through dry spells

The county has seen 0 weeks of drought over the past year, keeping the area at 0.0% severe drought levels. Despite this current abundance, using smart controllers for your sprinklers helps maintain this stability during future dry periods. Deep, infrequent watering encourages the deep root systems necessary to withstand California’s unpredictable water cycles.

Start your green space today

In Zone 10a, warm-season grasses like St. Augustine or Hybrid Bermuda thrive, though Tall Fescue remains a popular cool-season choice. With the last spring frost typically occurring on February 25, you can begin seeding early in the year. Prepare your ground now to take advantage of the long, mild growing window that lasts until December.

Lawn Difficulty Score

21/100
Easy
Rainfall46/100
Soil Quality0/100
Temperature7/100
Growing Season40/100
Drought0/100

Soil Summary

pH

N/A

Texture

N/A

Drainage

N/A

Organic Matter

N/A

View full soil details

Recommended Grasses

Warm-SeasonTransition Zone

Bermudagrass

Cynodon dactylon

Drought: 5/5Shade: 1/5
Suitability80%
View Seeds
Warm-Season

Bahiagrass

Paspalum notatum

Drought: 4/5Shade: 2/5
Suitability76%
View Seeds
Warm-Season

Seashore Paspalum

Paspalum vaginatum

Drought: 3/5Shade: 2/5
Suitability72%
View Seeds
Warm-Season

St. Augustinegrass

Stenotaphrum secundatum

Drought: 2/5Shade: 4/5
Suitability68%
View Seeds

Climate Snapshot

Annual Precip

25.4"

Growing Degree Days

2,921.317

Base 50F

Last Spring Frost

02/25

First Fall Frost

12/12

Days Above 95F

14

Hardiness Zone

10a

Seeding Calendar — Zone 10A

J
F
M
A
M
J
J
A
S
O
N
D
Warm Seed (Best)
Warm Seed (OK)
Warm Seed (Best)
Warm Seed (OK)
Optimal (cool)
Acceptable (cool)
Optimal (warm)
Acceptable (warm)

Seasonal Lawn Care Checklist

Spring

  • Apply pre-emergent herbicide when soil reaches 55F
  • Begin mowing when grass reaches 3 inches
  • Start irrigation if rainfall is below 1 inch/week
  • Soil test every 2-3 years — adjust lime or sulfur as needed

Summer

  • Raise mowing height to reduce heat stress
  • Water deeply 1-2 times per week (1 inch total)
  • Avoid fertilizing cool-season grasses in peak heat
  • Scout for grubs and treat if >10 per sq ft

Fall

  • Overseed warm-season lawns if thinning
  • Apply fall fertilizer (highest N application for cool-season)
  • Continue mowing until growth stops
  • Rake or mulch leaves to prevent smothering

Winter

  • Apply pre-emergent for winter weeds
  • Service mower and sharpen blades
  • Plan spring soil amendments based on fall test
  • Overseed with ryegrass for winter color

Watering Deficit Calculator

50020,000 sq ft

Monthly Deficit

1.4"

inches of water

Monthly Water

4,405

gallons

Estimated Monthly Cost

$35.24

at $0.008/gallon average

Estimates based on 25" annual precipitation and estimated evapotranspiration. Actual costs vary by local water rates.

Want detailed soil composition, drainage classes, and soil series data? View soil details on SoilByCounty.com

Data sourced from USDA SSURGO, NOAA Climate Normals (1991-2020), USDA Plant Hardiness Zone Map, and US Drought Monitor. Lawn difficulty scores and grass recommendations are estimates for informational purposes only.