The Certified Professional Horticulturist (CPH) program is designed for the mastery of basic horticulture and continuing education to build on your knowledge and skills. As a CPH, you’ll join an outstanding group of peers who’ve chosen to enhance their stature and attain this high level of professional excellence.
Simply follow these five steps:
Step 1: Certified Professional Horticulturist Study Materials
Sustainable Gardening is the primary horticultural text covering basics like botany, plant propagation, entomology and more. It is purchased through WSU cooperative extension. WSNLA provides a supplementary packet covering basic landscaping, plant nomenclature and identification. Click here for details about study materials.
Step 2: Pass the Certified Professional Horticulturist Exam
A written exam tests your skills and knowledge as a horticultural professional based on study materials and practical applications. The test is administered twice yearly by the WSNLA Certification Board, in March and October. Upcoming Exam Details.
Step 3: Demonstrate work experience
You must prove the equivalent of one year of work experience (2000 hours) with a licensed nursery, landscape contractor or WSNLA-approved business or institution.
Step 4: Fill out the paper work
After passing the exam, file for certification and provide work experience statements from your employer. Students are allowed two years to obtain necessary work experience and receive a Letter of Qualification until they qualify for full CPH certification. Congratulations, you are now a CPH!
Step 5: Maintain your Certified Professional Horticulturist certification
As a CPH, your continued education is required to maintain and update your credentials and skills. There is an annual renewal fee due each year. Every three years, your certification is renewed upon completion of 15 Continuing Education Credits. It’s easy: every hour spent equals one credit. Fifteen hours in three years is all it takes. WSNLA produces a variety of qualifying seminars each year. Credit is also given for seminars from relevant professional organizations or accredited institutions and teaching horticulture. You’ll receive complete information about maintaining certification when you enter the program.
History of the Certified Professional Horticulturist Certification
In 1978, WSNLA created a two-pronged professional certification program that has known as the Washington Certified Nurseryman or Washington Certified Landscaper. In 2005, WSNLA revamped and upgraded the certification program and renamed the designation as Certified Horticultural Professional. With nearly 400 Certified Professional Horticulturists, the CPH program is the largest community of state certifications serving professional horticulturists in Washington State.
WSNLA offers numerous seminars throughout the year, as stand-alone events, in conjunction with other organizations, or as part of chapter meetings and the annual convention. Continuing education offerings are designed for both owners/managers and line employees and are aimed at all segments of our membership.
CPH Credit Policy
Registration for Exam
& Prep Courses
CPH Plant List
Pay Annual Dues
CPH Credit Form
Why Hire a CPH
Who we are &
how we can help
Locate a CPH
Holly Osborne, CPH