About Us

Our Mission

The Iowa State University Soil and Plant Analysis Laboratory (SPAL) is part of the Department of Agronomy in the College of Agriculture at Iowa State University. We provide soil, plant, water and environmental testing services to farmers, fruit and vegetable growers, landscape managers, home gardeners, researchers, etc. in the State of Iowa and to researchers across the nation.

The lab provides cost-effective analytical testing and research-based limestone and fertilizer recommendations to support sustainable management decisions.

We proudly serve as a teaching laboratory for several Department of Agronomy classes.

Sample Submission and Quick Links


We participate in the North American Proficiency Testing Program (NAPT) and we are a Certified Soil Testing Laboratory in Iowa (IDALS) to perform limestone analysis for certification purposes.

Payment Policy

All orders for Soil, Plant Tissue, Compost and/or Greenhouse Media testing must be accompanied with payment. For purchase orders please contact the lab. All other orders must be accompanied with a check made out for the total amount payable to ISU Soil and Plant Analysis Laboratory. When samples are received without payment, lab personnel will contact customers in order to collect payment.

IMPORTANT: Samples received without payment will be held for two weeks before being discarded.