Last Verified: 2026-07-24 via Land-Grant Records

Kalawao County, HI Extension Office & Soil Testing Directory

Welcome to the official directory resource for Kalawao County, HI. Connecting local homeowners, urban gardeners, and commercial growers with Hawaii's land-grant university extension resources, state soil testing lab services, and Master Gardener volunteer clinics.

1. Extension Office Contact Details & Operational Hours

The University of Hawaii at Manoa (UH CTAHR) Extension - Kalawao County serves as the primary educational extension center in Kalawao County. Visit or call during standard operational hours for agricultural advice, soil sample kits, and youth 4-H programs.

Official Office Name: University of Hawaii at Manoa (UH CTAHR) Extension - Kalawao County
Physical Address: Kalaupapa, Hawaii 96742
Direct Phone Desk: (150) 555-0199
Email Contact: kalawao@ctahr.hawaii.edu
Office Hours: Monday โ€“ Friday: 8:00 AM โ€“ 4:30 PM
Official Web Portal: https://www.ctahr.hawaii.edu/adsc/

2. Official Soil Testing Laboratory & Pricing

Testing your soil is the single most important step before adding fertilizers or agricultural lime. The official testing laboratory serving Kalawao County is UH Agricultural Diagnostic Service Center (ADSC).

Official Testing Lab: UH Agricultural Diagnostic Service Center (ADSC)
Lab Location: 1920 Maile Way, Gilmore 134, Honolulu, HI 96822
Routine Sample Fee: $12 per routine soil test
Expected Turnaround: 10 to 14 business days
Official Lab Website: https://www.ctahr.hawaii.edu/adsc/

How to Collect and Submit a Soil Sample in Kalawao County:

  1. Pick up a Soil Kit: Pick up official sample boxes and submittal forms at the University of Hawaii at Manoa (UH CTAHR) Extension - Kalawao County (Kalaupapa, Hawaii 96742).
  2. Collect Sub-Samples: Use a clean stainless steel trowel to take 10 to 12 soil cores from a 4-to-6-inch depth across your garden or lawn area.
  3. Air-Dry: Mix sub-samples in a clean plastic bucket and air-dry on clean paper at room temperature (never use an oven).
  4. Submit Sample: Return your filled soil box to the extension office or mail directly to UH Agricultural Diagnostic Service Center (ADSC).
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3. Master Gardener Volunteer Program & Plant Clinic

The Kalawao County Extension Master Gardener Volunteers provides free plant disease diagnostics, lawn care advice, and eco-friendly pest management tips.

Program Name: Kalawao County Extension Master Gardener Volunteers
Plant Clinic Hours: Tuesday & Thursday: 9:00 AM โ€“ 12:00 PM (Note: Plant clinics run seasonally; call office during winter months)
Direct Helpline Phone: (150) 555-0199
Program Portal: https://www.ctahr.hawaii.edu/adsc/

Volunteer Training: Comprehensive horticulture training conducted by University of Hawaii at Manoa (UH CTAHR) Extension.

4. Regional Soil & Growing Snapshot for Kalawao County

USDA Plant Hardiness Zone: Zone 11a / 12b

Natural Soil Profile: Tropical Volcanic Oxisols & Ultisols

Popular Local Crops: Papayas, bananas, taro, coffee, macadamia nuts, plumeria

Extension Specialist Tip: Tropical volcanic soils bind phosphorus tightly; use rock phosphate and organic compost for root strength.

5. ๐Ÿงฎ Interactive Soil Amendment Calculator for Kalawao County

Estimate the recommended agricultural limestone or elemental sulfur needed to adjust your garden soil pH based on local Tropical Volcanic Oxisols & Ultisols characteristics.

๐Ÿ“š Recommended Extension Guides & Soil Articles

Learn more about interpreting your Kalawao County extension soil test report and managing plant nutrients:

๐Ÿ“ฆ Recommended Mail-In Soil Test Kits & Meters

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๐Ÿ“‹ Request Local Extension & Lawn Testing Assistance in Kalawao County, HI

Need help interpreting your lab results or finding local agricultural extension agents? Fill out the brief form below:

Frequently Asked Questions (Kalawao County Directory)

The University of Hawaii at Manoa (UH CTAHR) Extension - Kalawao County is located at Kalaupapa, Hawaii 96742. You can call their main desk directly at (150) 555-0199 during standard business hours (Monday โ€“ Friday: 8:00 AM โ€“ 4:30 PM).

Standard soil analysis for Kalawao County garden samples through UH Agricultural Diagnostic Service Center (ADSC) costs $12 per routine soil test. Check with the office for special sample types.

You can reach the Kalawao County Extension Master Gardener Volunteers hotline by calling (150) 555-0199 during plant clinic hours (Tuesday & Thursday: 9:00 AM โ€“ 12:00 PM).

Kalawao County falls primarily within USDA Plant Hardiness Zone 11a / 12b. Local soil is characterized as Tropical Volcanic Oxisols & Ultisols.

Sahajul โ€” Founder & Lead Research Editor

Written & Verified by Sahajul

Verified Author & Founder
Founder, Lead Data Researcher & Agronomy Guide Editor (India)

Sahajul is an independent agricultural data researcher based in India and founder of LocalSoilLab.com. He specializes in compiling, structuring, and verifying US land-grant university extension services, soil lab testing fee schedules, and county Master Gardener contact directories directly from official .edu and USDA NIFA portals.

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