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!


Pumpkin Centerpiece Workshop 2018

This workshop is SOLD OUT! Thanks for your interest. Our next workshop will be the Wreath workshop on December 1.

Join the UC Master Gardener Program of Colusa County to learn how to make a Pumpkin Centerpiece.


October 18, 6-8pm

Market Street Grill

415 Market St., Colusa

Click here to pay.


Pumpkin Centerpiece 18

Do you want to become a Master Gardener?

The UC Master Gardener Program of Colusa County is now accepting applications for our 2019 training.

Training will start February 6 and end May 22. The training will occur in Yuba City but you will volunteer in Colusa County.

The Meet the Master Gardeners informational meeting is January 3 at noon. Applications are due at this time.

Download an application here.

Complete application, 2019

October in the Garden

What to plant:

  • Cool-weather annuals like pansies, violas, snapdragons can be transplanted now.  Also, you can direct seed cornflower, nasturtium, poppy, nigella, portulaca and sweet peas.
  • If you don’t have a winter garden, consider planting a cover crop to be tilled in next spring.
  • Direct seed peas, spinach, radishes, lettuce, and carrots.
  • Early in the month you should buy your new bulbs and refrigerate them for six weeks before planting them in the garden.
  • October is also good time to consider reducing the size of your lawn. You can still rejuvenate a lawn with over-seeding.
  • Put your spent annuals and vegetables (disease-free, of course) in your compost pile.
  • Add compost to the beds that had the annuals and vegetables you are pulling out, before re-planting in those beds.
  • This is also the month to dig, divide, and re-plant overgrown perennials that have finished blooming. Be sure to clear out any weeds that developed in the perennial bed.
  • Check azaleas, gardenias and camellias for leaves yellowing between the veins. Apply chelated iron if this condition is present.
  • If you had glads, dahlias or tuberous begonias they should be dug up and cleaned after the foliage dies. Store the corms and tubers in a cool, dry place.
  • Be sure to deadhead your roses following the October bloom.
  • Keep your compost bin covered with a plastic tarp when rains begin.



Water Trees First

TRIC lawn

Our trees are the most important garden asset. They provide shade, clean the air, provide habitat for wildlife, they are beautiful and increase your property value.

A new way of irrigating trees have been developed by the University of California. As you see in the picture you will circle the tree with a drip line or soaker hose to the edge of the canopy. You can purchase supplies at your local garden center or hardware store.

To get the deep watering need for trees, you will need to run the drip line for several hours but only irrigate every 2-4 weeks. The water needs to penetrate the soil about 2-3 feed deep.

For more information from the California Center for Urban Horticulture, click here.


Water-wise tips



Create drought resistant soil

  1. By incorporating 2-4 inches of compost into the soil you will increase the water holding capacity of the soil.
  2. Topdressing compost around plants will reduce water needs but not up to the plant base.       Space @ the base.
  3. Mulch all exposed soil to reduce evaporation with bark, leaf litter or rocks


  • Reduced water usage


Grow California or Mediterranean natives

Check out the UC Arboretum All-Stars

  1. Plants thrive with little irrigation
  2. Planting in the fall allows the roots to grow without competition
  3. Irrigate until established
  4. Minimize high water use ornamentals


Cal Iris

  • Reduce watering
  • Reduce trimming
  • Reduce fertilizing
  • Reduce spraying


Minimize the Lawn

  1. The use of native groundcovers, grasses, shrubs and trees make an eye catching garden
  2. Reduce the size of the lawn and plant Tall fescue. It is a cool season grass that does well in summer. Most cool season grasses need a lot of water to look good
  3. Avoid slopes, plant a ground cover instead of lawn


Min lawn

  • Conserve water
  • Conserve energy
  • Conserve labor        



  1. By grouping plants together by water and light needs plants tend to be healthy
  2. When you group your plants together by water and light needs then you can properly water each micro-climate
  3. Use California natives


  • Healthy plants
  • Conserve water
  • Less pruning


Irrigation System

  1. Remember to change your irrigation timer seasonally. Monthly adjustments are encouraged
  2. Use an automatic controller on your irrigation system
  3. Use drip for your flower and shrub beds
  4. Replace old sprinkler heads with high efficient ones. If your system is over 10 years old check out the new sprinkler heads at your local garden center
  5. Use multiple run times if you have a lot of run-off before the timer shuts off.  For example; you should irrigate every other day for 20 minutes but after 15 minutes the water is running off the lawn. Instead run the system for 10 minutes, wait 1 hour and run for another 10 minutes. This works especially well on slopes.


  • Limit evaporation and run-off
  • Limit disease
  • Limit weeds


Irrigate according to the season

  1. Know your watering needs
  2. Adjust watering to the season, use chart in Lawn Watering brochure
  3. Water early
  4. Water slowly
  5. Water deeply


  • Appropriate watering slows plant growth
  • Promotes plant health
  • Reduces pruning and mowing
  • It is estimated that overwatering causes 85% of all landscape problems


Make every Drop Count                 

  1. Water wisely and slowly.
  2. Mulch is one of the quickest, easiest and most cost-effective ways to save water
  3. Repair leaks and broken sprinklers
  4. Reduce overspray areas
  5. Adjust the system frequently to the season
  6. Mulching exposed soil reduces evaporation.
  7. Prevent urban drool


  • Conserve water
  • Save money
  • Urban landscape water use can be reduced by 50%


Help your trees survive the drought

More information:

8 Smart Gardening Practices

How to save water in your garden

Keep Plantings Alive under Drought Conditions

Lawn Watering Guide for California

Lawn Watering

Rules of Thumb for Water Wise Landscape

Water Conservation checklist

Water Conservation Tips



California Garden Web

UC Guide to Healthy Lawns

River Friendly Landscaping

UC Davis Arboretum

UC Master Gardeners of Sacramento County

UC Master Gardeners of San Joaquin County



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

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Garden Advice and Workshops



 This workshop is sold out!

Pumpkin Centerpiece Workshop

October 18, 6-8 pm

Market Street Grill

415 Market St., Colusa

$25 per person



Master Gardener Blog

Science Café: Ask a Scientist a Question, Such as 'Are There Upper Limits to Human Lifespan?'

Many senior citizens who develop new hobbies (such as rearing monarch butterflies) believe this keeps their brain active and leads to greater enthusiasm for life. Supercentarian Jeanne Calment of France lived to be 122. One of her interests was playing the piano. (Photo by Kathy Keatley Garvey)

If you've ever wanted to ask a scientist a question, here's your opportunity. Ask away at the Science Café. This is an informative scientific presentation held the second Wednesday of each month in the G St. Wunderbar, 228 G St., Davis. The...

Posted on Wednesday, October 3, 2018 at 5:00 PM
Focus Area Tags: Environment Health Innovation

Updated Landscape Weed Info

Mallow (cheeseweed). [Credit: Jack Kelly Clark]

Controlling weeds can be challenging to landscape professionals or home gardeners since landscapes often include a mix of turfgrass, annual plants, herbaceous perennials, shrubs, and trees. The newly revised publication Pest Notes: Weed Management in...

Posted on Wednesday, October 3, 2018 at 10:53 AM
Tags: control (30), herbicide (4), IPM (51), landscape (23), manage (2), management (21), nonchemical (2), pest (57), plants (11), UC IPM (193), weeds (19), Wilen (10)
Focus Area Tags: Pest Management Yard & Garden

This Katydid Did

Honey bees circle  a fork-tailed bush katydid feeding on a yellow rose. (Photo by Kathy Keatley Garvey)

The katydid, as green as the leaves around it, is feeding on a yellow rose. It is paying no attention to the circling honey bees. The bees want nectar, not an encounter with a critter far bigger than they are. The katydid slowly moves from one...

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