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 720 hours and made 977 face to face contacts in 2015/16.


This is what we do!

Click here for a short video!


St Paddy's Day Terrarium

St Paddy's day

Join the UC Master Gardeners of Colusa County at Rocco's for a fun night of terrarium making.

When: Tuesday February 28, 6:30 to 8pm

Where: Rocco's Bar and Grill, 546 Market St., Colusa

Cost: $25 per person  (limited to 20 people)

Deadline: February 24

Appetizers and beverages are available to purchase from Rocco's.

Click here to pay.

If you are having problems paying, try using the Firefox browser.

Make an Online Gift to UC Master Gardeners

Preparing for a Frost




Before a frost

  • Identify cold spots in the landscape by monitoring with thermometers
  • Identify plants at risk: citrus, succulents, tender perennials, tropical and subtropical plants.
  • Have supplies ready: sheets, blankets or frost cloths, lights, wraps for trunks, thermometers, stakes or framework to hold covers off foliage. Frost cloths come in different weights that can provide 4 to 8 degrees of protection. Because the frost cloth allows some light and air to penetrate, it can stay on plants for a few days at a time. Frost cloth can lie directly on plant foliage.
  • Prepare tender plants: avoid fertilizing and pruning after August to minimize tender new growth.
  • Rake away mulch to allow soil to warm up during the day and radiate heat into the plant at night.
  • MONITOR weather forecasts and note how low temperatures will be and for how long.

o   Local frost: clear, dry nights, usually warms during the day.

o   Hard freeze: temperature inversion or Arctic front, can last for days or weeks, are very damaging.

When a frost is forecast

  • Move plants to a warmer spot next to the house or under a patio cover, especially on the south side.
  • Check that plants are well watered because dry plants are more susceptible to damage, and moist soil retains heat better than dry soil.
  • Cover plants before sunset to capture ground heat radiating upward at night. Remove sheets, blankets and other covers daily if it is sunny and above freezing to allow soil to absorb heat.
  • Add heat by using outdoor lights: hand 100 watt drop lights or holiday string lights to interior of plant. Use the old C7 or C9 large bulbs, not new LED lights which do not give off heat. Old style holiday lights that give off heat can provide up to 3 degrees of protection. Use lights, extension cords, and multi-outlets or power strips that are rated for outdoor use and grounded (3-prong). Avoid connecting together more than three light springs in a line.
  • Wrap trunks of tender trees if a hard freeze is expected, using towels, blankets, rags, or pipe insulation. Also wrap exposed pipes the same way.
  • Harvest ripe citrus fruit. Generally both green and ripe fruit are damaged below 30 degrees, but there is some variation by species.


For more information, click here to visit the UC Master Gardeners of Sacramento County page on frost protection.

Thank you, UC Master Gardeners of Sacramento and San Joaquin Counties for the information.


February in the Garden

In the Garden

  • Around Valentine’s Day apply dormant copper spray to peach and nectarine trees no later than bud swell.
  • Fertilize mature trees and shrubs after spring growth starts.
  • Be sure to remove and discard (do not compost) fallen camellia blossoms to reduce petal blight.
  • Fertilize spring blooming and fall-planted perennials.
  • Mulch 3 inches deep around plants (without touching stems) to conserve soil moisture.
  • Plant in vegetable garden by direct seeding: radishes, beets, chard, and peas.
  • Start tomato, pepper and eggplant seeds indoors.
  • Flowers to transplant or direct seed: snapdragon, candytuft, larkspur, coral bells, and stock.
  • Plant bulbs for summer bloom: dahlias, begonias, gladiolus, lilies, etc.
  • Plant potaotes


  • Finish pruning roses.
  • Prune summer blooming shrubs now.

Pest and Disease Control

  • Watch for aphids on spring blooming bulbs; remove with a strong spray of water.
  • As the weather warms prepare to battle slugs and snails with traps or pet-friendly baits.

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


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Garden Advice and Workshops

Colusa Farm Show

February 7, 8, 9

Main Exhibit Hall

Colusa County Fairgrounds

St Paddy's Day Terrarium class

February 28

6:30 - 8pm

Rocco's Bar and Grill

546 Market St


$25 per person


Featured Plant


California fescue


Medium size

California native




Master Gardener Blog

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Any day's a good day when you find the ootheca (egg case) of a praying mantis in your yard. It's much better than finding an Easter egg. Ootheca comes from the Greek word "oo," meaning egg and the Latin word, "theca," meaning a cover or container. A...

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Posted on Sunday, February 26, 2017 at 5:29 PM
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