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!

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.


Garden and Home Show /Mulch Theme       

The  Jefferson County Master Gardeners just finished their turn at planning and building the annual CSU Extension educational garden at the Colorado Garden and Home Show. We chose the theme "Mulches for Every Garden." In the six sections of the exhibit we showed how different kinds of mulch can be used effectively in the home landscape and vegetable garden.

Woodland garden In this section, we created a sort of woodland setting to show a mulched home landscape using pine needles and recycled bark/wood chips. We also developed signs containing bullets of “quick information” about the   mulches.  Thanks to a donor, we were able to include a meandering flagstone path throughout to complete the setting.

Two sections were devoted to vegetable gardening and these were fun and a bit challenging to create in the dead of winter.

In one garden, we laid straw (or grass clippings) over a few layers of newspapers, which helps control weeds by blocking light. (The grass clippings were collected last fall and sun dried to be ready for the show.) As we set up the garden, we cut out a section of the newspaper and pushed back both straw and grass mulch to show how drip irrigation lines should be installed first and underneath the materials.

The other vegetable garden demonstrated the use of plastic films over soil where warm-season vegetables are grown.

Plastic mulches

Black plastic (left) warms the soil; tomatoes grown in red mulch (middle) yield more fruit and reflective silver mulch (right) deters various insects. One of the most wonderful parts about this garden was the use of tomatoes in fruit!


Two sections were devoted to “living mulch” in both shade and sun locations. Living plants generally are more attractive than the typical bark, straw or grass mulch.  When placed in beds with other plants having similar light needs, the effect was almost ethereal.

Coral bells

The pairing of coleus(middle ground) and coral bells (background) with the shade-loving ground covers was especially effective.  Living mulches do require continual care and maintenance compared to non-living ones, but the textural differences and colors showed how attractive it can be.





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: churley@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.

Web Resources