UCCE Master Gardeners of San Joaquin County
University of California
UCCE Master Gardeners of San Joaquin County

Advice To Grow By

ACP (Asian citrus psyllid) found in San Joaquin county

You may have heard that ACP (Asian citrus psyllid) was found in Lodi and Manteca. The Master Gardeners are ready to answer your questions about this invasive pest. Click here to find out how you can help prevent the spread of this unwanted pest and what to do if you think you have it.

Winter Frost Protection Tips

When the weather report calls for freezing temperatures overnight, you don’t want to be rushing outside in the dark to cover your cold-sensitive plants. Here are some tips for being prepared.


  • Water the soil thoroughly (except around succulents). Wet soil holds heat better than dry soil, protecting roots and warming air near the soil.
  • Bed sheets, drop cloths, blankets and plastic sheets make suitable covers for vulnerable plants. Use stakes to keep material, especially plastic, from touching foliage.
  • Remove the coverings when temperatures rise the next day.
  • For a short cold period, low plantings can be covered with mulch, such as straw or leaf mold. Remove once the danger of frost has passed.
  • Place a 100-watt lamp designed for outdoor use in the interior of a small tree. It can emit enough warmth to reduce frost damage. Holiday lights (not the LED type) serve a similar function, but be sure they don’t touch any covering materials.
  • Spray an anti-transpirant, available at your local nursery, on the foliage of cold-sensitive plants to seal in moisture. One application can protect up to three months by coating the leaves with an invisible polymer film.
  • Cluster container plants close together and, if possible, in a sheltered spot close to the house.

Don’t overreact to plant damage
Plants can be remarkably resilient. If you see signs of frost damage, do not prune off the affected parts or dig up the plant immediately. This is especially true for palms. Wait until the weather warms up in March to see whether new leaves sprout. You may see healthy new growth at the base of the plant, at which point you can prune out the damaged parts. If no regrowth is noted, remove the dead specimen and replace it with a more cold-tolerant species.

For more information, the University of California has a downloadable publication titled Frost Protection for Citrus and Other Subtropicals. To read this full article, click here.



What's Growing On - SJMG Blog

Spring Pruning in the Caliornia Native Garden

Manzanita pruned to reveal the beautiful bark and branching structure

Like most ornamentals grown in the garden, California native plants look better with a late winter or early spring clean-up. New growth is likely to be emerging soon with our unseasonably warm weather, so now is a good time to get out in the garden and...

Posted on Friday, February 27, 2015 at 8:00 AM
  • Author: Nadia Zane

Planning a Water Efficient Landscape


When we think about saving water in the garden, the first things that usually come to mind are irrigation systems and low-water plants. Another crucial factor is hydrozoning, or the grouping of plants by water and sun requirements; the ultimate goal is...

Posted on Tuesday, February 24, 2015 at 4:35 PM
  • Author: Nadia Zane

Keeping Backyard Poultry Healthy


You may have heard that the United States Department of Agriculture's (USDA) Animal and Plant Health Inspection Service (APHIS) has confirmed the presence of highly pathogenic (HPAI) H5N8 avian influenzain a commercial turkey flock in Stanislaus County,...

Posted on Monday, January 26, 2015 at 12:50 PM
Tags: bird flu (1), chickens (1), H5N8 (1), poutry (1)

Valley Gardener's Journal For Year-Round Blooms

The San Joaquin Master Gardeners are excited about the Valley Gardener's Journal For Year-Round Blooms. This garden journal is now available for purchase and is great for any gardener. For more info click here!  

Page Last Updated: February 26, 2015
Webmaster Email: mdhachman@ucdavis.edu