Hawaii Extension & Soil Testing Directory
Find your local Hawaii County Cooperative Extension office, official state university soil analysis lab, and Master Gardener volunteer plant clinics.
🔬 State Soil Testing Laboratory
Official Lab: UH Agricultural Diagnostic Service Center (ADSC)
Standard Fee: $12 per routine soil test
Turnaround Time: 10 to 14 business days
State residents can obtain soil sample bags and submittal forms at any local county extension branch.
🌱 State Growing Conditions
Soil Types: Tropical Volcanic Oxisols & Ultisols
Hardiness Zones: Zone 11a / 12b
Popular Crops: Papayas, bananas, taro, coffee, macadamia nuts, plumeria
Tropical volcanic soils bind phosphorus tightly; use rock phosphate and organic compost for root strength.
Featured County Directories in Hawaii (5 Listings)
Hawaii County
Extension Office: University of Hawaii at Manoa (UH CTAHR) Extension - Hawaii County
Soil Lab Fee: $12 per routine soil test
Phone: (150) 555-0199
Honolulu County
Extension Office: University of Hawaii at Manoa (UH CTAHR) Extension - Honolulu County
Soil Lab Fee: $12 per routine soil test
Phone: (150) 555-0199
Kalawao County
Extension Office: University of Hawaii at Manoa (UH CTAHR) Extension - Kalawao County
Soil Lab Fee: $12 per routine soil test
Phone: (150) 555-0199
Kauai County
Extension Office: University of Hawaii at Manoa (UH CTAHR) Extension - Kauai County
Soil Lab Fee: $12 per routine soil test
Phone: (150) 555-0199
Maui County
Extension Office: University of Hawaii at Manoa (UH CTAHR) Extension - Maui County
Soil Lab Fee: $12 per routine soil test
Phone: (150) 555-0199
📦 Recommended Mail-In Soil Test Kits & Meters
FTC Affiliate Disclosure: We may earn a commissionIf you need immediate results without waiting for university mail-in lab turnaround times, these top-rated professional home soil test kits provide fast pH, N, P, and K diagnostic analysis:
MySoil Soil Test Kit
Professional mail-in kit analyzed by accredited labs. Returns 13 essential nutrient values (N, P, K, pH, Micronutrients) & customized fertilizer recommendations via app.
Luster Leaf Rapitest 1601
Popular color-comparator kit for 10 instant soil tests (pH, Nitrogen, Phosphorus, Potash). Includes tailored plant preference chart.
Sonkir 3-in-1 Soil Tester
Instant probe sensor for soil moisture, pH, and sunlight levels. Requires no batteries. Perfect for potted plants, lawns, and raised beds.
📋 Request Local Extension & Lawn Testing Assistance in Hawaii Statewide
Need help interpreting your lab results or finding local agricultural extension agents? Fill out the brief form below:
Frequently Asked Questions: Hawaii Soil & Extension
How do I get my soil tested in Hawaii?
To test your soil in Hawaii, collect 10 to 12 soil cores from a depth of 4 to 6 inches across your garden or field, air-dry the sample indoors, fill out your county extension submission form, and submit it to UH Agricultural Diagnostic Service Center (ADSC) or your local county extension office.
How much does soil testing cost in Hawaii?
Routine soil fertility analysis in Hawaii typically costs $12 per routine soil test. Turnaround time for results is usually 10 to 14 business days.
Does every county in Hawaii have a Cooperative Extension Office?
Yes. Every county in Hawaii is served by the state's Land-Grant University Extension system. While our directory highlights primary regional office hubs and university labs, local extension agents serve horticulturists, farmers, and home gardeners across all counties in Hawaii.
Written & Verified by Sahajul
Verified Author & Founder
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.