UC Master Gardeners, Santa Clara County, CA
University of California
UC Master Gardeners, Santa Clara County, CA

December Tips

Garden Help > Monthly Tips

Monthly tips are categorized by To-Dos, What to Plant, or Pests and Diseases. Scroll through the list to see items in each category. Also, refer to our list of tips useful for any month.

1. To-do

  • Clean Garden Beds -

    In preparation for winter, remove dead plants, leaves, fruit (mummies) and flowers from garden beds. Many insects and diseases overwinter in fallen debris. Do not compost any plant materials you think might be diseased.

    - December
  • Holiday Ideas -

    Prune your evergreen trees and shrubs now and use the cuttings for holiday wreaths.

    Christmas cactusChristmas cactus, poinsettias, cyclamen, kalanchoe, amaryllis and more help make the house look festive at this time of year. They prefer cool temperatures, so find a place for them away from a heating vent. To avoid over watering, check the soil and give them water only when dry.

    Consider a living Christmas tree that can later be planted in your garden. A smaller tree doesn’t have room for as many ornaments, but is more likely to adapt well when planted outdoors. You can even rent a tree from Our City Forest as it's on its way to a permanent home in the community.

    You can bring some of the beauty of your garden inside to decorate your home for the holidays. Consider some of these seasonal items for tree ornaments, mantle decorations, garlands, and wreaths: laurel leaves, lemons, pine cones, nuts, pyracantha berries, eucalyptus pods, grape vines, rosemary, and rose hips.

    - December
  • Prune Blackberries -

    Little or no pruning is required during the first year after planting. Blackberries should be pruned as soon as the harvest is completed. All wood that has produced the current crop should be removed. The canes should be trellised immediately after pruning. Put up only the larger canes and prune the small ones. Generally, no more than 9 canes should be put up on the trellis. A fan-like arrangement is the best way to trellis the vines. Tipping (removing the end of the canes) forces out the laterals on which fruits will be borne the following season. Consult our Berries page for more information.

    - December
  • Pruning Roses to Minimize Disease -

    A chemical-free way to keep roses healthy and minimize disease associated with foggy summer mornings is to prune to improve air circulation.

    Roses pruning photo from University of Illinois
    Make sure you wear gloves to protect your hands from thorns and use clean, sharp tools. First, remove dead and diseased parts. Then remove anything that is growing where it doesn’t belong. This includes suckers below the graft union and branches that are crossing or growing towards the middle of the plant. Finally, prune for shape and health. Cut back to about 4-6 evenly-spaced strong canes, leaving 3-5 buds on each cane. Make pruning cuts ¼ inch above outward-facing buds in order to create a vase shape that allows for good air circulation. Good air circulation allows the morning dew to dry and helps prevent rust and powdery mildew. 

    More Information: Rose Pruning

    - January, February, March, April, December
  • Poisonous Plants List -

    As we approach the holidays, there are a lot of questions on poisonous plants. Fortunately, many of these plants have a very bitter taste that limits the amount of the plant eaten.

    Poinsettia and mistletoe should be kept away from curious children, but the list includes other flowers and plants such as azaleas, calla lily, carnation, daffodil, foxglove, hydrangeas, iris, lantana, narcissus, poppy, sweet pea and tulips.

    Different parts of the plant may be toxic. Consult the UC Poison Plant web page for detailed information.

    - November, December
  • Wet Soil -

    The clay soils which dominate our area are particularly susceptible to compaction, especially when they have received a lot of rain. These soils are characterized by small mineral particles. Hence squeezing out the air spaces makes it more difficult for plant roots and soil organisms to get the oxygen they need to flourish. Try to avoid walking on or using heavy equipment on soil that is wet. Digging in wet soil can also destroy the structure, breaking up useful soil aggregates and earthworm tunnels. Try to wait until the soil is moist, not wet or dry, for easiest tillage. If you must walk or stand on the soil, use a board to distribute your weight over a broader area. Mulch can also create a bit of a cushion and help minimize compaction.

    - February, March, December
  • Winter Irrigation -

    Depending on the fall weather and rain frequency you will likely set your sprinklers to water less frequently or even turn them off for a while.  It's still important to check outdoor plants to make sure they have enough water.  While they need less water when it's cool, it's important to make sure they don't dry out.  If you have a lawn and rains haven't come, irrigate the lawn once or twice this month.

    If it has been raining, the soil may be saturated so be careful if you have to walk on it so as not to compact it.  Also if soil is waterlogged, vital space for air that is needed for plants and worms and excess water can drown beneficial soil organisms and contributed to rotting roots.

    - January, February, December
  • Frost Dates -

    The approximate first and last frost dates for Santa Clara County, depending on your location, are November 15 and March 15. These are important dates for gardeners to remember.

    • First frost date—this is the earliest date you should expect frost to occur. If you have plants that need to be brought in for the winter, or crops you need to pick before frost, this date will be important to you.
    • Last frost date—after this date, you wouldn't expect any more frosts. It's generally used as a milestone when pruning frost sensitive plants (such as citrus where you don't want to stimulate delicate new growth until danger of frost is past).
    • For our climate, last frost date is not a reliable metric for when to transplant summer vegetables. Daytime temperatures and soil temperatures are more important. See entries for individual vegetables for specific recommendations.

     

     Also see: Frost—Avoidance and Dealing with Damage

    - January, February, March, November, December
  • Fruit Tree Dormant Care -

    If you've had major pest infestations on your fruit trees this year, now is a good time to use dormant oil sprays. These are used to reduce overwintering populations of insects. They work by smothering soft-bodied insects and eggs when applied at the proper times in the life cycles of the pests. See our Fruit Tree and Vine Care Calendar for more information.

    - December
  • Prune Apple Trees -

    Once your apple tree loses its leaves, it's time to think about pruning. Apple trees produce fruit terminally on spurs located on wood 2 yrs. to 8 yrs. old. Weak and unproductive branches should be thinned out to allow the sunlight into the tree for good spur development. Older spurs can be rejuvenated by cutting back, especially following a light crop year. Tree height is maintained by cutting back upper branches to shorter laterals. Excessive pruning of a bearing tree can negatively affect its vigor and fruit. Consult our Fruit Tree Pruning page for more information.

    - January, February, December
  • Winter Fruit Tree Pruning -

    Pruning tools: saw, loppers, and hand pruners, by Allen Buchinski
    Pruning Tools – Keep them clean and sharp

    Remember to keep your pruners and loppers sharp. Good pruners use bypass blades rather than anvil type. Anvils have only one cutting blade and one flat blade which can result in "smashing" the plant material. Sterilize the pruners or loppers between each plant and after cutting off any diseased plant material. Use a 10% bleach solution (1 part bleach, 9 parts water) or disinfectant bathroom cleaner.

    What and When to prune

    According to UC's Backyard Orchard website, "the optimum time of year to prune fruit trees is the dormant season, December, January (best) and until the middle of February." Apricots are the exception for pruning in January; they should be pruned in the summer after harvest. If you properly prune and care for fruit trees you will get the highest yield of fruit. A good rule of thumb is to prune plum, pluot, apple, and pear trees 15-20%; and peaches 50%.

    Deciduous trees can be pruned anytime during their dormant season (in winter). Prune deciduous species, such as Western spice bush, creek dogwood, Western mock orange, red-bud, maples and deciduous oaks.

    Do not prune apricot and cherry trees in winter because they are susceptible to Eutypa dieback. The best time to prune them is late August before the rainy season starts.

    While you're outside pruning, remember to pick up any rotting fruit on the ground at the same time.

    Pruning Tips:

    Make your cuts with care in order to direct the growth for next year. Check the tree for crossing branches, broken branches, diseased wood, and old leaves and fruits. Clean out suckers, light branches, and trim the branches that grow vertically. After that, you can start to shape the tree with cuts for form and fruit production. To have an open tree with good air circulation, make cuts above outward-facing nodes. Choose nodes where you want new growth and make a cut about 1/4" above, refer to the image below.

    Pruning stages
    Also refer to our page on fruit tree pruning page.

    - January, February, December
  • Dormancy and Chill Hours -

    The positive side of cold weather is that fruit trees native to colder climates, such as cherries and blueberries, may get the chill hours they need to produce good fruit. Going dormant saves energy which can then go into fruit development. No need to protect them on cold nights. Knowing the native habitat of your plants will guide you in caring for them. Mimicking the success of nature leads to greater success in your own garden.

    Learn more about chill hours on the UC Fruit & Nut Information website. UC has historical chill hours available for many locations in California, however, Gilroy is the only location located in Santa Clara County. For county locations closer to the Bay, the Union City station may be more applicable (or view a map of all station locations).

    - January, February, December
  • Paint Fruit Trees to Prevent Sunburn -

    After deciduous fruit trees have dropped their leaves, paint tree trunks with white latex paint diluted 1:1 with water to prevent sunburn. Preventing sunburn helps trees resist invasion by shot hole borers, which are tiny beetles that boreholes and lay eggs in the cambium layer of the tree. When the eggs hatch, young larvae feed and excavate tunnel galleries in the wood. For more information about identification and control see UC Pest Note on Shothole Borer.

    - November, December
  • Fruit Tree Grafting -

    When pruning dormant fruit trees, you may want to save cuttings (scions) for later grafting onto other fruit trees.  Grafting is a technique that allows you to have multiple varieties of compatible fruit on one tree and is a great space saver. Fruit trees can have new varieties grafted to them when they are dormant in January and February.

    Scions are available in January at the California Rare Fruit Growers (CRFG) scion exchange. Their January event also includes training classes. Check the CRFG - Santa Clara blog for the date.

    More information on grafting can be found at:

    - Grafting and Budding on the UC Home Orchard website
    - Grafting Dormant Deciduous Fruit Scions at the California Rare Fruit Growers website
    Budding and Grafting Demystified from the UCCE web site

    - January, February, December
  • Certified Arborists -
    Whether you prune your own trees or hire someone, it’s important that whoever does the job knows at least a little about tree anatomy, plant health, and the purpose of the plant (shade? privacy? fruit?). Knowing the difference between heading cuts and thinning cuts, how to locate a node to direct growth, and how to open up a tree for air circulation are all part of good tree pruning. An improper pruning job can stress the tree, spread disease, invite pests, and promote weak branching. These can lead to breakage, damage, and injury. The cheapest bid may end up costing more in the long run due to damage repair, lawsuits, and additional fix-it pruning. Take a class or read tree pruning guides if you want to do a good job yourself. If you hire someone, it is strongly recommended that you choose a certified arborist who has been specially trained and is insured. The International Society of Arboriculture can help you find a certified arborist in your area.
     
    More Information: Tree Pruning Guide
     
    - January, February, March, December
  • Don't Fertilize Now -
    Except for cool-season vegetables and lawns, most plants will be dormant or growing very slowly during this time of year. Fertilizing is most beneficial when plants are actively growing or developing fruit or flowers. Even citrus which ripens during the winter is best fertilized for the last time of the year before October 1. Some California native plants are active in the winter, but they evolved in our native soil and generally do not need supplemental fertilization. Fertilizing plants now will create tender new growth right before the risk of frost. Some nutrients cannot be taken up efficiently by plants during cold weather. The excess can leach into the groundwater or run off and reach the bay. Ultimately, using unneeded additives is a waste of resources and money.
     
    More Information: Dormant Season
     
    - October, November, December
  • Leafy Salad Plants -
    Lettuce by Donna Lee
    Harvest your leafy vegetables early and often. Many leafy vegetables will bolt (go to flower) quickly if not harvested. When you harvest lettuce or similar greens, remove only the outer, older leaves. New leaves will continue to grow from the center and you'll be able to eat salads all winter long. Harvest head lettuce all at once when the head is full and firm.
     
     
    - January, February, March, November, December
  • Perennials and Bunch Grasses -
    Winter is a good time to cut back perennials and bunch grasses. You can cut back some perennials all the way to the ground. These include yarrow, hummingbird sage, goldenrod, California aster, and most kinds of California fuchsia. You can divide other perennials at this time, such as Douglas iris, alum root, seaside daisy, woodland and beach strawberry, yarrow, yerba buena, daylilies, and chrysanthemums.
     
    You can propagate bunch grasses, sedges, and rushes by division this time of year. Examples of bunch grasses are purple needle grass (state grass of California), fescues, blue grama, leafy reed, oat, and deer grass. Some sedges are the meadow, clustered field, and San Diego sedge. Rushes include the common rush and the California gray rush.
     
     
    - January, February, December
  • Mushrooms -
    Sometimes it seems like there are mushrooms all over: mushrooms in the lawn; mushrooms on the trees; mushrooms in fertilizer; mushrooms in the woods; there is even mushroom compost available. How do you know which mushrooms are desirable and which are not? This can be a life or death determination, both for you and for your plants. Mushrooms are the fruiting bodies we see of fungi which can be widespread and hidden underground or inside plants. Fungi play a beneficial role in decomposition and in providing nutrients to garden plants. Mushrooms in the lawn can be a sign of overwatering, so check the irrigation and drainage. You don't need to remove the mushrooms except to protect young children and pets from eating them. If cultivating or harvesting mushrooms to eat, be sure that you know it is not a poisonous variety.     
     
    More information: Mushrooms in lawns
     
    - January, February, December

2. What to plant

  • Camellias -

    Camellia japonica ´Professor Charles S. Sargent’, by Barbara H. Smith, Clemson Extension
    Camellias can be planted in fall through spring. Since they bloom in winter, choosing a plant now will ensure that you know the color, shape, and size of the flowers with which you will live for many years. Camellias are not native to our area so may need some extra attention in order to grow successfully. Our native clay soil does not drain well so it must be amended for camellias. Our alkaline soil needs to be acidified, and sulfur pellets are one way to achieve this. The plants need some shade and need to be kept moist. Mulch helps hold in moisture, and pine needles, redwood bark, and coffee grounds are all good organic materials that will break down over time and help improve the soil. Pick up flowers as soon as they fall to the ground to avoid the spreading of a disease called Camellia petal blight. 

    More information: Camellia Pests

    - January, February, March, April, May, September, October, November, December
  • Bare Root Plants -

    Bare root plants are sold without any soil clinging to the roots making them easier and less expensive to transport; they'll do just fine in the garden as long as you don't let them dry out before planting. Because you can see the roots and can control how they're placed in the soil, it helps reduce the chances for root girdling problems later. Buy and plant early in the month while roots are still fresh.

    The bare roots should be soaked from an hour to overnight (large plants) in a bucket of water before planting. Trim roots of broken, dead or spongy bits and carefully pull the roots apart. Dig a hole that is fairly shallow and wide. Spread the roots out sideways and have the crown of the plant several inches above the soil level. This is necessary as the plant will settle down over time. Water in well but wait to fertilize until you see new shoots growing. Be sure to water regularly if the rains are sparse. Staking may not be necessary.

    Trees aren't the only plants that are sold bare root. You can also plant bare root asparagus, artichokes, rhubarb, berries, kiwifruit, horseradish, rhubarb, grapes, roses, strawberries, and iris in January.

    - January, February, December
  • Onions -
    Onions, by <a href='https://www.extension.iastate.edu/news/yard-and-garden-growing-onions'>Iowa State University</a>
    Onions, by Iowa State University
    This is a good time to plant onions for nice big bulbs. Onions are biennial plants which means that they are programmed to go to seed in their second year. If they are planted too early in the year and grow too large before cold weather hits, they can be tricked in the spring into acting as if they are in their second year. This means that they will go to seed soon and put their energy into reproducing themselves rather than into growing large bulbs. Ideally, they should be no bigger than the thickness of a pencil when the cold weather causes them to go dormant. Plant onions from seeds if earlier in the fall or transplants if later. They do best in moist, well-drained soil. Harvest bulbs in the summer when the tops die back. You can plant green onions at any time and harvest them whenever they are about a quarter to half-inch in diameter.
     
    More information: Growing onions
     
    - November, December
  • Poinsettias -

    Poinsettias are a tropical plant so they'll do best in a warm sunny place in your house. The soil can easily dry out and become hydrophobic, so make sure to check the soil moisture regularly. There’s really no need to fuss over them if you’re only keeping them for a few weeks of holiday color. If you want them to bloom again next year, UC has Poinsettia Care Tips that describes what to do.

    Poinsettias are beautiful at this time of year due to being forced in commercial greenhouses. If you want to save yours for next year, you will also need to take measures to force bloom in time for the holidays (it's a little tricky, but here's how if you're interested). Did you know that the red parts are actually bracts (modified leaves) and that the true flowers are the little yellow parts in the centers? You can also plant them outdoors with protection from frost. They have been seen growing as tall as eight feet in San Jose, and taller in their native Mexico.

    - January, December
  • Amaryllis or is it Hippeastrum? -

    The showy red Amaryllis (more correctly called Hippeastrum) is a great bulb for growing indoors if you can’t wait for your outdoor bulbs to bloom in spring. Choose a pot just slightly larger than the bulb. Plant it in loose potting soil with a third of the bulb sticking up above the soil surface. Keep moist, but not so wet as to rot the bulb. The University of Minnesota Extension has information on general care and how to control blooming.


    Photos: UC Solano Master Gardeners, Growing Amaryllis or is it Hippeastrum?")

    - January, December

3. Pests and Diseases

  • Mistletoe -

    Mistletoe is a parasitic plant that reduces the vigor of the host tree and can threaten its survival, especially if it's drought weakened.

    Cut off affected limb 18" or more below mistletoe attachment. If this isn't possible, remove mistletoe and wrap the infected area with black plastic to kill any resprouting. More information about this plant is in the UC Pest Note on Mistletoe.

    - December
  • Oak Root Fungus -

    This fungal infection, Armillaria Mellea, also known as mushroom root rot, honey fungus and shoestring fungus can cause foliage to become sparse and eventually kill the tree. The white or cream-colored fungus will grow between bark and wood of roots and up into the lower part of the tree trunk. It smells like your typical grocery store mushroom.

    In spring or fall there may be mushrooms growing around the base of the infected tree. If the disease has not progressed too far, you can cut out infected tissue and expose the base of the tree and roots to air. Reduce watering especially close to trunk. No chemical treatment is known to be effective.

    Plants Resistant or Susceptible to Armillaria mellea, The Oak Root Fungus by Robert D. Raabe contains more detailed information. The UC Master Gardener video Revealing Root Rot can help with detection of two common root pathogens and provide guidance on how to reduce the spread.

    - December
  • Peppertree Psyllids -

    This pest can cause damage to California pepper trees. The damage is done when the insect is in its immature stage. They make doughnut-like pits on leaves that wrinkle or twist the leaves as well. Parasitic wasps can provide satisfactory control. See the UC Pest Note on Psyllids for more information.

    - December
  • Peach Leaf Curl Preventive Care -

    To prevent peach leaf curl, use resistant peach and nectarine varieties where possible (the Pest Note linked below provides a list.) For non-resistant varieties, treat trees with a fungicide such as a fixed copper spray every year when the trees are dormant (typically December to January). When applying any fungicide, it is essential to cover the trees to the point of runoff or until they are dripping to obtain adequate disease control.

    Generally, a single early treatment when the tree is dormant is effective, although in areas of high rainfall or during a particularly wet winter, it might be advisable to apply a second spray late in the dormant season, preferably as flower buds begin to swell but before green leaf tips are first visible.

    More Information: Peach Leaf Curl Tips from UC

    - January, February, December
  • Cabbageworms -

    Examine your cabbage and broccoli plants for imported cabbageworms. Larvae are green and very hairy, with an almost velvet-like appearance. Handpick the worms. The adult cabbage butterfly is white with one to four black spots on the wings; they are often seen fluttering around the fields. Whitish, rocket-shaped eggs are laid singly on the undersides of leaves. The cabbageworm is active throughout the year in California. Use row covers or screening to keep the adults out of your vegetables. For more information see UC Pest Note on Imported Cabbageworm.

    - October, November, December
  • Snails and Slugs -

    Beer trap for snails and slugs, UC, by Jack Kelly Clark
    Escargot may sound good on a plate, which is where the French who brought this delicacy to California in the 1850s intended for the ingredients to stay, but they escaped into gardens where they became pests. Brown garden snails are the most common ones we see (or don’t see) eating our plants. Signs of their presence include holes in fruit rinds and leaves, not necessarily at the edges, and slime trails. They tend to hide in dark damp places during the day and come out mostly at night. The best times to find them are at night with a flashlight, early in the morning, or during and right after heavy rain. They can be hand-picked and crushed or put in a bucket of soapy water. Gloves are recommended, especially with the shell-less slugs. Creating hiding places, such as laying a wooden board over a section of the garden, will draw them to that location so you can find and dispatch them in the morning. Copper barriers and beer traps are other options. If you do use snail bait, those made with iron phosphate are not toxic to pets and wildlife.

    More information: Snails and Slugs

    - January, February, March, April, December
  • Sooty Mold -

    If your citrus leaves have a black coating, you may have a sooty mold problem. This black mold can also be seen on citrus fruit, avocado leaves, magnolia leaves, hibiscus, other host plants, and even on sidewalks beneath trees.

    The sooty mold fungi grow on “honeydew”, a sticky substance excreted by plant-sucking insects such as aphids, scale, mealybug, and whitefly. They suck the sap out of plants and excrete excess sugars. It exists purely on the surface of a plant and is not a systemic issue. By itself, the fungi cannot kill the plant but it can coat the leaves to the extent that sunlight is prevented from reaching the leaf surface, thus reduce photosynthesis. 

    Ants protect the sucking insects from their predators so they can eat the honeydew. Keep ants out of trees and away from honeydew-producing insects by applying a sticky compound such as Tanglefoot on a tape wrapped around the trunk.

    Pruning branches to allow better air circulation also helps. You can hose off the mold itself with a strong jet of water. And you can eat the fruit once you wash off the sooty mold.  
     
    For more information, see Sooty Mold Management Guide.
     
    - August, September, October, November, December
  • Limes -

    Blossom End Rot on a Bearss Lime
    Blossom End Rot on a Bearss Lime
    Limes are easy to grow in our area and make a pretty addition to the landscape. They don’t take up as much space as some other citrus and can grow well in our native soil with plenty of sun. They need some fertilizing and occasional protection from the cold. Bearss Lime is a popular variety that has fruit ripening now. Other favorites include Mexican Lime, Australian Finger Lime, and a Limequat hybrid. Most limes are yellow when fully ripe and have a higher juice content at this stage; most limes in stores are green because they have a longer post-harvest life or shelf life. A tan, leathery sunken area at the end of the fruit is called blossom end rot in citrus. It can come from insufficient water, preventing calcium from getting all the way to the ends of the fruit (similar to blossom end rot in tomatoes.) You can freeze the fruits whole for year-round margaritas or whatever it is you do with your limes. Freezing weakens the cell walls, which makes it even easier to juice the limes after thawing.

    More Information: Growing Citrus Fruits

    - January, November, December
  • White Mold on Lettuce and Brussels Sprouts -

    White mold is a distinctive disease that most often affects stems and foliage at the base of cole crops* and lettuce plants. Affected tissue develops a soft, watery rot and white, cottony mycelium forms on the surface. Plants may wilt if stems are girdled by the decay. As affected tissue dries up, it turns yellow to white, and hard black sclerotia form on the surface or inside the dead stems. Get more information in the UC Pest Note on White Mold.

    * Cole crops include broccoli, Brussels sprouts, cabbage, cauliflower, collards, kale, and kohlrabi

    - November, December
  • Mosquitoes -
    Make sure you don’t have any water sitting around from our late rains. Mosquitos breed in standing water and can pass along deadly West Nile Virus to people. Check and dump water from any buckets, pots, saucers, dishes, or wheelbarrows. Put containers away or turn them over to avoid collecting additional water. Keep chemicals balanced in swimming pools. Ponds, fountains, and bird baths can also be breeding grounds. Add mosquitofish to these bodies of water to eat mosquito larvae. They are an environmentally friendly means of control and are available free of charge from Santa Clara County Vector Control.
     
    More Information: Mosquito Management
     
    - January, February, March, April, May, October, November, December
  • Don't Move Firewood -
    Tree-killing insects and diseases can lurk in or on firewood. These insects and diseases can’t move far on their own, but when people move firewood, these pests can jump hundreds of miles. Beetles that have done significant damage in Southern California are the Goldspotted Oak Borer and Invasive Shot Hole Borers. Let’s keep them out of Santa Clara County.
     
     
    - January, December
  • Armillaria Root Rot -
    Mushrooms at the base of a tree could signal a problem with the tree. Armillaria is a fungus that can live in the soil for many years. It can rot the roots and cause leaves and branches to die and can eventually kill a plant. Another common term is Oak Root Fungus, although it affects many different species of trees and even some herbaceous plants. Often by the time the fruiting bodies (mushrooms) are visible, much damage has already been done. It feeds on both live and decaying wood. Cutting back a small section of bark can reveal white fan-shaped or black stringy fungus which aids in diagnosis. Keeping the plant healthy provides some defense. Fungi thrive in moist conditions, so do not overwater the area. Also, keep mulch and other plants away from the trunks of trees so as not to hold moisture against the crown (base). The best defense against this disease is to plant resistant varieties.
     
    For information: Armillaria Root Rot
     
    - January, February, December

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