About WhenToPlant

Last updated: March 29, 2026

Our Mission

Every spring, 80 million American gardeners ask the same question: "When should I plant this?" The answer depends on where you live, what you're growing, and whether you're starting from seed or transplanting.

We built WhenToPlant to answer that question in ten seconds. Enter your zip code, pick your plant, get your dates. No signup, no jargon, no 2,000-word article to wade through.

Who We Are

WhenToPlant is built and maintained by Pete, a web developer and home gardener in Tacoma, Washington (Zone 8b). After years of searching for straightforward planting date information and finding it buried in university PDFs or scattered across cluttered websites, he decided to build the tool he wished existed.

This site is part of a portfolio of focused, tool-first reference sites designed to answer specific practical questions as quickly and accurately as possible.

How We Built This

Our planting date calculations combine two data sources: frost date averages from NOAA's 30-year Climate Normals database and plant-specific growing requirements compiled from university cooperative extension services, seed company references, and established gardening literature.

When you enter your zip code, we look up your USDA hardiness zone and average frost dates. When you select a plant, we apply that plant's specific timing requirements (how many weeks before or after frost to start seeds, transplant, or direct sow) to calculate personalized planting dates for your area.

For a detailed breakdown of our data sources and methodology, visit our Data Sources page.

Our Approach

We believe gardening information should be accessible, accurate, and free. Our planting guides are written in plain language for every experience level — from first-time gardeners to seasoned growers. We explain terms like "hardening off" and "direct sow" instead of assuming you already know them.

We cite our data sources. We tell you how our calculations work. We let you know when a date is an estimate based on averages, not a guarantee. Honesty and transparency are more important to us than appearing authoritative.

Contact Us

Questions, corrections, or suggestions? We'd love to hear from you.

Email: hello@whentoplant.net

You can also visit our contact page.