Horticulture Program

This page is your source for horticultural programs and class offerings through Jefferson County Extension.  You’ll also find many links to useful on-line resources!

Colorado Master Gardener Classes have begun - interested in next year?
If you’re interested in the Colorado Master Gardener program or the Colorado Gardener Certificate, the 2016 program is filled and under way. However, if you would like to consider the 2017 program, we will be happy to let you know as soon as the application packets and information are available (some time in the fall).

Contact Patti O’Neal (303-271-6633, poneal@jeffco.us) or Mari Hackbarth (303-271-6642, mhackbar@jeffco.us) for information.

Gardening Help

Master GardenerHave a gardening question?  Call the Master Gardener hotline (303)271-6632 to get personalized help with your specific situation.  You can also email questions and pictures to Master Gardeners from May through September only, at mastergardener@jeffco.us.

You can also check our pest update page for the latest landscape and garden problems reported to us. Our "Common Garden and Landscape Problems" page covers plant problems according to the season.

    Plant Diagnostic Clinic

Jefferson County Extension has an on-site walk-in plant diagnostic clinic staffed by trained personnel   in plant forensics, plant, insect and landscape weed identification.  Before bringing a sample to the clinic, check this link for instructions on the type of sample to collect.

Samples may be dropped off anytime during normal business hours: 8 am to 5 pm, Monday through Friday.  We try to complete your diagnosis within 3 business days. Fees apply.


Schedule an appointment now: kecuster@jeffco.us or 303.271.6620 for a lawn expert to evaluate your lawn and its trouble spots.  Fees apply.

Demonstration and Research Gardens

Plant Select garden

Our two on-site gardens are open to the public. The Plant Select garden offers beautiful displays of water-wise and climate tested plants.  There’s a kiosk in the garden containing information on the plants and their growing requirements.



The Horticulture Research and Demonstration contains on-going studies including blueberry production, apple tree training, tomato and pepper variety trials and innovative vegetable garden season extension tools.  We are also developing an insectary garden to attract beneficial insects.

Jeffco Horticulture Calendar

Web Resources