Science based solutions for Colusa County's gardening communities.
This is what we do!
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.
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
December in the Garden
* Shop: Plants and seeds make awesome holiday, hostess and mystery gifts
Living Christmas trees
Bare-root fruit and landscape trees
Adjust your irrigation
Protect citrus and other sensitive plants
Apply dormant spray
Add mulch to beds
Throw out fallen rose leaves
Catalogs are arriving to get you excited about what to plant next year. You might want to consider removing some lawn area and creating a new planting bed to make room for all the new plants in the catalogs.
UC Master Gardeners of Colusa County
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
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
Winter Fruit Tree workshop
Saturday January 10, 2015, 1-3pm
Details to come.
Rose Pruning workshop
Sunday January 25, 2015, 1-3pm
Details to come.
Master Gardener Blog
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