Colusa County
University of California
Colusa County

Master Gardeners


 Science based solutions for Colusa County's gardening communities.

The UCCE Master Gardeners of Colusa County volunteer's donated 834 hours and made 1191 face to face contacts in 2017/18.

Since 2009, we have volunteered 5,798 hours and made 11,447 face to face contacts in Colusa County.


This is what we do!

Click here for a short video!



Need help identifying insects and how to get rid of them? The UC IPM (Integrated Pest Management) has answers!

UC IPM website


March in the Garden

  • Check your irrigation system and do necessary maintenance.
  • Fertilize roses, annuals flowers, and berries with slow-release fertilizer when spring growth begins.
  • Fertilize citrus and deciduous fruit trees.
  • Watch for aphids on new growth on the roses; spray with a strong spray of water to remove them, or use insecticidal soap or horticultural oil spray.
  • Prepare garden beds by incorporating compost before planting spring vegetables. You can plant lettuce, carrots, and cilantro directly in the vegetable bed. Mid-March is a good time to plant potatoes.
  • You can plant canna, gladiolus, and crocosmia for summer blooms. Early in the month you can still plant bare-root trees and shrubs if the garden center still has any.
  • Don’t be tempted by the plants in the garden centers unless you have a way to warm up the soil. It is still early for tomatoes, eggplant and peppers (although you could try late in the month if it is still warm.) Nights should be above 55°.
  • Prune and fertilize spring-flowering shrubs and trees after they finish blooming.
  • Fertilize the lawn with a slow release fertilizer.
  • Keep on the weed patrol; pull them while they are small.
  • Use iron phosphate bait for slugs and snails or go on a night hunt and kill them up when you find them.

Asian Citrus Psyllid

Asian Citrus Psyllid is an insect that carries a devastating disease in Citrus trees and there is no cure. The insect and disease is usually detected in home citrus first. Click here to read more about the Asian Citrus Psyllid and the Huanglongbing disease.

The Asian Citrus Psyllid has been found in San Joaquin County.

Click here to read about the Asian Citrus Psyllid from the UCCE Master Gardeners of San Joaquin County.

Click here for Spanish


UC Master Gardeners of Colusa County

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The University of California Master Gardener Program provides the public with UC research-based information about home horticulture, sustainable landscape and pest management practices. The program is administered by local University of California Cooperative Extension (UCCE) county offices that are the principal outreach and public service arms of the University’s division of Agriculture and Natural Resources.

The UC Master Gardener program supports sustainable gardening practices that protect the environment, conserve natural resources, and take into consideration each gardener's lifestyle and goals.


What do UC Master Gardeners do?

UC Master Gardeners are trained to help residents of California become better gardeners. Using a variety of activities such as workshops, lectures, and garden hotlines these volunteers answer questions about home horticulture, sustainable landscaping, and integrated pest management using University of California research-based information.

After their training UC Master Gardeners are qualified to help the public with problems in areas such as:

  • Weed Control
  • Plant Problem Diagnosis
  • Integrated Pest Management (insect and pest control)
  • Soils, fertilizers and irrigation
  • Selecting and caring for fruit and landscape trees
  • Growing annuals, perennials and food crops
  • Lawn care
  • Vegetable Gardening
  • Plant Pathology
  • Composting


Each county develops programs to address local needs. Some typical activities are:

  • Using mass media to disseminate gardening information
  • Teaching workshops, or lecturing on gardening practices
  • Participating in research activities with academics within UC
  • Answering gardeners’ questions via email or helplines
  • Speaking to the public on horticultural and gardening topics
  • Manning county fair information booths
  • Consulting with gardeners to improve their landscape practices


Make an Online Gift to UC Master Gardeners

Find us on Facebook



Garden Advice and Workshops

Second Saturday at the Library

10 to noon

Colusa Library

Landscape Tree Workshop

Saturday March 16, 10 to noon

Williams Community Center, 860 C Street, Williams


Garden Chat with the Master Gardeners

Last Tuesday of the month

1-2 pm

Arbuckle Library



Master Gardener Blog

When Irish Eyes Are Smiling...There Must Be a Green Insect Nearby

The female metallic green sweat bee, Agapostemon texanus, nectaring on a purple coneflower. (Photo by Kathy Keatley Garvey)

When Irish eyes are smiling, it could be... St. Patrick's Day is approaching or A green insect is nearby  If you've ever seen the female metallic green sweat bee, Agapostemon texanus, or the sand wasp, Bembix americana, you can't help but...

Posted on Friday, March 15, 2019 at 7:18 PM
Focus Area Tags: Environment,Innovation,Natural Resources

The Science of the Monarch Butterfly: For Graduate Students and Citizen Scientists As Well!

A longhorned bee, Melissodes agilis, targets a monarch nectaring on a Mexican sunflower (Tithonia) in Vacaville, Calif.(Photo by Kathy Keatley Garvey)

If you're a graduate student at the University of California, Davis, you can enroll in a newly announced spring quarter course, "The Science of the Monarch Butterfly,"   taught by Art Shapiro, distinguished professor of evolution and...

Posted on Thursday, March 14, 2019 at 4:55 PM
Focus Area Tags: Agriculture,Environment,Innovation,Natural Resources

A Gathering of UC Davis Entomologists

UC Davis forensic entomologist Robert Kimsey, known as

It's a gathering of UC Davis entomologists--from students to graduates to faculty to retired faculty. The UC Davis Entomology Alumni Reunion is set Sunday, March 31 through Tuesday, April 2 at the Odd Fellows Hall, 415 2nd St., Davis. Co-chairing the...

Posted on Wednesday, March 13, 2019 at 5:25 PM
Focus Area Tags: Agriculture,Environment,Natural Resources,Pest Management
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