Updated Pacific Northwest Gardener’s Handbook, tools for acidic soils

Each month, experts at Washington State University present free online guides that help inform growers and improve communities.

Aimed at Northwest gardeners and farmers, the newest publications from WSU Extension include a comprehensive handbook on Pacific Northwest gardens and a look at a new soil-improving calculator tool.

Lime Requirement Estimates for the Inland Northwest: A Guide to the Updated Calculator

Lime is used by growers to ameliorate acidic soils. This guide offers region-specific recommendations for liming and links to the Lime Requirement Calculator, a tool that helps growers more accurately determine how much lime is needed in acidic soils to improve crop yields, protect soil health, and maximize returns. Authors include Joao Antonangelo, WSU Assistant Professor of Applied Soil Chemistry; Rachel Wieme, WSU Regional Extension Agronomist; and Carol McFarland, Associate in Research, WSU Department of Crop and Soil Sciences.

Revised Publications

Pacific Northwest Gardener's Handbook: Growing for the Future

WSU Extension's definitive gardening resource is newly revised in 2025. This 28-chapter, 620-page handbook is a multi-year culmination of expertise covering the fundamentals of gardening as well as advanced horticultural knowledge. Contributors include more than 40 authors from WSU as well as partner institutions including the Washington State Department of Agriculture, Oregon State University, South Seattle Community College, the City of Seattle, King County, the United States Botanic Garden, and others.

The WSU Extension Publications website offers a wide range of resources, from agricultural and natural resource guides to materials on 4-H, economic development, energy, and more; as well as Spanish-language guides. Find the latest releases at the site's new products page.