Is a greenhouse in your gardening future?

My greenhouse constructed mostly of salvaged materials.

It will soon be time to start seeds in my greenhouse. I built the greenhouse from material that I scrounged over several years and finally got around to putting it all together about 10 years ago. I have enjoyed my greenhouse so much that I wish that I had built it much sooner. There is something indescribably relaxing to be with seeds and plants in a cozy, warm, greenhouse when the outside weather is foul.

There are several things to consider when planning and installing a green house. Is there a site on your property that will provide the solar inputs needed for the green house to work?  Shading by trees or other buildings is generally undesired and orientation is important. The long axis of the green house should face south and it can be as much as 20 degrees off true south toward the west to optimize solar exposure.

True south is where the sun is at noon so you can use that as a guide or a magnetic compass, but you will need to adjust the compass reading for true north by the declination value for the area. I prefer the sun at noon which is simple to do this time of year. This is also the best time of year to see if there are shade obstructions to your site as the sun is low in the sky and winter and early spring is the time when a greenhouse is most useful.

To what purposes will you use your green house is another consideration. If you only plan to over winter frost-sensitive plants then perhaps you don’t need electricity.  However, if you are going to actually use it for starting plants from seeds or cuttings then water and electricity are very important and you will need to consider this in locating the greenhouse. It is also important to have good drainage and, if possible, shelter from wind which can diminish interior heat. My greenhouse is on the south side of a shop building and therefore electricity was easy to access and the building blocks north winds. It is also good to have a wide path to the green house for moving plants, compost, potting materials, etc. to and from the structure with a garden cart or wheel barrow.

I built my shed green house of glass panels. My neighbor had worked at a glass shop and had saved some 2 ft x 6 ft. glass panels for years and generously gave them to me for the roof to get them out of his garage. I also had saved some patio glass doors that I relieved someone of at the dump 25 plus years ago. I used these for the south facing wall. The back of the green house was covered with redwood boards I salvaged from the old tank house that blew over in a 1978 December storm. The frame I made from new 4×4 redwood posts and 2×4’s.

Out-fitting the green house, once built, is the next job. A bench space makes it is easier to work with plants and it runs the length of the greenhouse. It was decked with salvaged redwood fence boards. If you are starting plants from seed—lettuce, tomatoes, peppers, eggplant or flowers—in January or February you will need some heat supplied by heating mats and you will need auxiliary lighting on a timer. Day length is too short for plants at this time of year so I provide about 14 hours of fluorescent lighting to the plants once they have germinated.  Otherwise you will end up with leggy, spindly plants that are reaching for more light. I achieve this using a

Grow rack with lights and heating mats for starting seeds

grow rack with shelves for the heat mats and lights above them and a timer that controls all the lights. I had this setup in a garage, but after I built the greenhouse, I moved the grow rack into my greenhouse. After the plants are growing and day length increases, I transplant them to pots and move them to the bench.

There can be too much heat in a greenhouse. Hence a fan on a thermostat is good at controlling temperatures and a shade cloth may help reduce solar inputs in late winter when the sun is ascendant. Solar powered vents can also reduce temperatures on small greenhouses.

You can buy very nice greenhouses to meet your needs. You can buy them in kit form to be assembled. One very helpful website for planning and building your own greenhouse is: ( It is a matter of your capabilities, budget and what your needs are, but if you are an avid gardener, you will love having a greenhouse.

If you have a gardening related question you can contact the UC Master Gardeners at 209-953-6112. More information can be found on our website:

Posted in Uncategorized | Leave a comment

Please no crepe murders

Crepe myrtles are best left natural or pruned correctly

Winter is almost here and time to dormant prune ornamentals, roses and fruit trees. I am disturbed to see how some people despoil crepe myrtles (Lagerstroemia indica) when they prune them. The pruning technique used is called pollarding and it is defined as a tree cut back nearly to the trunk, so as to produce a dense mass of branches. Perhaps Wikipedia says it best about pollarding crepe myrtles “This is not a practice to use if one wants an attractive, healthy natural tree as the natural growth is stunted. Many times this is done in southern states of the USA to crepe myrtles, and is called “crepe murder” by some.” I can testify that I have seen crepe murder in our county.


Actually, crepe myrtles are better left unpruned than murdered. They will produce fewer blooms as there is less new growth which encourages blooms, but they are much more attractive with the natural look. Part of the charm of crepe myrtles is the bark, so leaving lots of the tree structure to display its colorful, peeling bark is so much better than pollarding it. Leaves are a gorgeous crimson each fall providing another esthetic feature.

Because crepe myrtles bloom on new wood, pruning does encourage new growth and that is why they are often pollarded to provide new growth. However, there are more esthetic and healthier ways to assure this. I came up with my own method years ago and two years ago while visiting the UC Davis campus, I saw that others too had used the same approach to pruning crepe myrtles.

Crepe myrtle pruned as an open vase

I train crepe myrtles like a fruit tree with an open center as seen in the photograph. This openness allows sunlight and air into the center, reducing diseases such as powdery mildew and promotes new growth for blooms. A heading cut on a young tree at about 3 to 4 feet will create branches to be trained to an open vase. There is a tendency for the crepe myrtle to have multiple trunks, but I prefer to select one main trunk and work with it. However, you can create an open vase tree with multiple trunks from the ground, especially if you start to work with a tree established in this manner: see  Select no more than 3 to 5 well-spaced trunks and prune out the rest. Crepe myrtles often send up suckers near the base which should also be removed.

After selecting a single trunk, it is a matter of making choices of which of the new shoots will be selected to create the vase shape of the tree. Select no more than 3-5 main scaffold branches. I usually head these at 2-4 feet or so to encourage branching. These branches in turn can be headed at 2-3 feet the following year to produce secondary scaffolds. At some point when the tree is shaped and at a sufficient height, I truncate the new shoots to a two bud spur. The choice is often for spurs which will keep the tree opening up. Pay attention always to which way the buds are facing on your two-bud spur selection as well as scaffold selections. Buds are usually located opposite each other in alternating sets, i.e., the next set is 90 degrees from first, so in some cases leaving 4 buds will provide the best directions for the shoots because the top buds will usually dominate. Last year’s two-bud spur may produce two or three shoots, so you will need to reduce this to one to select the next two-bud spur.

You can keep the tree at whatever height you want. By selecting two bud spurs on each branch each year, you will only add about a foot to the tree in 6-8 years. If you want to shorten the tree you can cut back into old wood and the tree will push some vestigial buds and continue to bloom. Thus this method allows you to keep the tree at a reasonable height. I need a ladder to prune my trees, but you could keep the tree shorter if desired and staying off ladders is always safer.

Prune weak side growth to strengthen it and induce more vigor. This will help provide blooms in places other than at the top. More evenly distributed blooms are more appealing. Crepe myrtles come in a range of sizes and colors to suit your landscape needs. They do well in California and are drought tolerant as well as beautiful. Cheers to better pruning and enjoyment of crepe myrtles.

If you have a gardening related question you can contact the UC Master Gardeners at 209-953-6112. More information can be found on our website:


Posted in Uncategorized | Leave a comment

Garden fungi: harmful or beneficial?

With the arrival of drenching fall rainstorms, soils are replenished with moisture and mushrooms pop up with abandon, seemingly overnight. “Are they bad?” you ask. The answer: it depends.

There are more than 100,000 species of fungi worldwide. Approximately 10 percent of them cause plant diseases, while only one-tenth of a percent are harmful to animals. The vast majority of fungi are beneficial to the environment: they help decompose decaying plant matter into rich humus and nutrients, break down toxic chemicals into non-toxic ones, or act in ways that encourage plant growth.

The terms “fungi” and “mushroom” are often used interchangeably, but they’re not the same thing. Think of a fungus as a living iceberg with only the upper tip visible. The above ground protrusion we know as a mushroom is simply the visible reproductive “fruit” of the main, seldom-seen fungal structure called the mycelium, which is a tangled mass of microscopic, threadlike filaments called hyphae. The mycelium grows where the fungus’s food source is located: in the soil, in rotting wood or plant matter, or in a host plant. A mature mycelium produces fruiting bodies called sporangia, and a mushroom is simply a very large sporangium. Each sporangium contains vast numbers of miniscule spores (the fungal equivalent of seeds). Once the spores ripen they disperse, germinate, and sprout new hyphae. Most fungi require warm, moist conditions to grow.

Lawn fungus mushrooms (Photo by Jack Kelly Clark, UC IPM)











Most common garden mushrooms—“toadstool” types or puffballs—grow on or near the ground and are beneficial decomposing fungi. The same applies to the shelf-like mushrooms that grow on dead trees or wood. However, if fungal mats or mushrooms sprout from a living tree, this indicates a potentially severe problem, since rot is already present. The more insidious fungus Armillaria mellea actually attacks many trees and shrubs and produces clusters of golden brown mushrooms.

Puffball fungus with black spores (Photo by R. Michael Davis, UC IPM)











If you prefer to remove mushrooms from your lawn or garden because they’re unattractive or because they might be eaten by young children or pets, simply hand pick and dispose of them as they emerge. NEVER eat wild mushrooms unless you’re an expert in their identification. Some mushrooms are harmless, but many are poisonous and can cause symptoms ranging from temporary vomiting to permanent and fatal organ damage.

The beneficial mycorrhizal fungi deserve special attention. These fungi form symbiotic associations with the roots of many plant species; the word mycorrhiza literally means “root fungus” in Greek. Once these fungi colonize plant roots they spread their fine hyphae out into the soil, helping plants absorb water and nutrients far more efficiently than they could on their own. In exchange, plants “feed” the fungi with sugar compounds. Some plants are highly dependent on this partnership—especially oaks, conifers, and many native shrubs—and 90 to 95 percent of plant species are believed to benefit from fungal symbiosis.

Mycorrhizal fungi play an important role in helping plants survive drought conditions, but they can survive only in association with living plants, not in bare soil. To encourage a healthy population of these fungi, keep soil planted year-round, minimize soil-disturbing activities like rototilling, and avoid the use of pesticides and chemical fertilizers.

Some fungus species are pathogenic, and cause harmful plant and turf diseases such as anthracnose, powdery mildew, rust, root rot, leaf spot, and blights. Landscape conditions such as poor air circulation, excessive moisture, improper watering, and over-fertilizing encourage many of these fungal diseases. Proper cultural care practices are usually very effective in controlling the responsible fungi without the use of chemicals.

Most fungicides are preventive (not curative) and can only protect uninfected plant tissue; they must be used before infection occurs or when symptoms first appear. If it becomes necessary to use a fungicide treatment, research the affected plant and type of fungus carefully, choose the proper product, and apply it according to label instructions to avoid causing harm to yourself and the environment. Remember that pesticide labels are legally binding documents; it’s both dangerous and illegal to apply or dispose of pesticides in a manner inconsistent with the instructions.

For more information on fungi see the UC IPM Pest Note entitled, “Mushrooms and Other Nuisance Fungi in Lawns.”

For advice on gardening related questions, call the UC Master Gardener office at 209-953-6112, or use our website.




Posted in Uncategorized | Leave a comment

The magic of persimmons

A persimmon tree in fall is a splendid sight. Its leaves turn vibrant shades of yellow, orange, and red, and once they drop the decorative, bright orange fruits remain hanging from the bare branches like well-placed ornaments.

The two most common persimmon varieties, and one lesser-known one, are:

Fuyu: The medium-sized, flattened fruits of this variety are shaped like a common tomato, and they ripen to an orange or orange-red color. Their flesh is orange, firm, crunchy, and sweet when ripe, and they are best eaten raw like apples.

Hachiya:The large fruits of this variety have pointed ends and are shaped like plump acorns; they are deep orange-red when ripe. If you mistakenly bite into one before it’s fully ripe, you won’t repeat the mistake, since the flesh of this variety is highly astringent when firm and it will leave your mouth unpleasantly dry. Once allowed to become soft-ripe, the flesh becomes very sweet, without astringency. It can then be scooped from the skin with a spoon, to be eaten fresh or used in baking.

Chocolate: The ripe fruits of this variety are shaped and colored like those of Hachiya. Interestingly, the inner flesh is astringent and light-colored if the fruit is left un-pollinated and seedless, but the flesh turns sweet, slightly spicy/chocolaty, and brown when pollinated and seedy.

Fuyu persimmons (Photo courtesy of Sonoma County Master Gardeners)

Hachiya persimmon (Photo courtesy of Sonoma County Master Gardeners)


Harvesting and storing

Persimmons begin to ripen in September and are ready to harvest in November. Harvest Fuyus when fully colored and firm. Hachiya persimmons can be allowed to get soft-ripe while still on the tree, but it’s easier to harvest them when brightly colored but still firm. They will finish ripening indoors.

Cut the stems about 1 inch above the fruit, leaving the four-lobed green calyx at the top. Don’t pull the fruits off the tree since this can damage them or break the brittle branches.

Once harvested, keep the crisp-ripe Fuyu persimmons away from fruits that emit ethylene gas (apples, bananas) or they will lose their firm texture. The opposite is true for Hachiya persimmons intended for use in baking or for eating raw; ethylene gas will hasten their ripening to a soft and non-astringent state.

Persimmons can be stored for up to a month in the refrigerator; remove them to allow the ripening process to finish, if necessary.

Preserving persimmons

If you’d like to enjoy persimmons throughout the year, you can preserve them using a couple different methods:

Dehydrated slices: Begin with firm-ripe and fully-colored Hachiya or Fuyu persimmons; interestingly, the dehydration process removes the astringent quality of the firm Hachiya persimmons while preserving and concentrating the sweetness. The skin may be left on the fruit, but blemishes and bruises should be cut away. Slice the persimmons across the core into evenly thick slabs ¼ to ⅓ inch thick. Arrange slices on the dehydrator trays and dry at 120° for 7 to 10 hours until they are leathery but still flexible. The vibrant color of the persimmon fruit is preserved, and the sweetness is enhanced. Store slices in airtight bags or containers in the refrigerator.

Hoshigaki: This is the traditional Japanese version of dried persimmons. The drying process is long and the end results are decidedly unattractive, but the flavor is delicious. To prepare hoshigaki, start with persimmons that have ripened to a bright orange color but that are firm (not soft-ripe) and un-bruised. Hachiyas work best, but Fuyus can also be used. Wash the persimmons and break off the calyx “leaves,” but retain the stem. Peel off the rind, then tie string securely to the stem. Hang the persimmons in a dry location (indoors or outdoors) that gets direct sunlight and good air circulation but is protected from rain and animals. Protect the surface underneath to protect from accidental falls and messy “splats.” Every 3 to 4 days, gently massage the hang-drying fruits to break up the internal structure, being careful not to split or tear the outer layer. Don’t worry if a white powder develops on the outside; this is sugar emerging to the surface. After 5 to 8 weeks, when the pulp has set, you’ll be rewarded with orange-brown, chewy relics having a sublimely sweet flavor.

For gardening related questions, call the UC Master Gardener office at 209-953-6112, or use our website:


Posted in Uncategorized | Leave a comment

Water Water, oh if it were only everywhere

A 1000 gallon tank used to water spring greenhouse plantings

The rainy season is here and it is a good time to think about conserving and saving whatever befalls us this season. NOAA’s Climate Prediction Center gives a 70 percent chance of La nina conditions to develop this fall and a 55 percent chance that it will persist through the winter. La nina conditions are characterized by cooler than average temperatures in the Central Pacific with a resulting cool and moist jet stream in the northern states and a drier jet stream in the southern tier of states. Hence dry conditions in Southern California and perhaps snow and rain north of San Francisco. Of course long range forecasting is an iffy proposition, but is seems unlikely that our county will have a wet winter.

So, what can we do to help with the drought which is likely to continue? We are already over drafting aquifers, so conserving water remains an essential activity and of course water is becoming more expensive which also encourages conservation. One approach is to plant drought tolerant plants and also to group plants by their water needs so that the irrigation can be hydro-zoned for efficient water use based on the plant’s water requirements.

Recently at the UC Master Gardener’s Demo garden open house, I helped retro-fit a sprinkler system with a drip irrigation setup for one of the gardens. We plugged all the sprinkler heads except for two. There two were installed with filters and we attached ½ inch drip lines with built in emitters at 18 inch spacing. This will save a lot of water as it puts the water right at the plant. Less water, fewer weeds are the benefits.  We used Netafim drip materials and for more information on using drip for landscapes you can find it here:

To keep water on your property where it does the most good rather than running down storm drains there are several things that you can do. Redirect water from driveways, walkways and hardscapes. This can be done by putting plastic or metal extensions and splashblocks on the downspout. This should also be done to keep water away from the house and foundation; see:

If hardscape have been constructed of porous concrete or porous asphalt materials this will allow water to drain through them. This is something to keep in mind if you replace any of these hardscapes in the future; see: Water kept on your property can replenish underground storage essential to landscape plants.

Water harvesting has been done in many areas of the world for 4000 years. Bermuda which consists of seven small islands was settled in 1609 and has very little potable water from aquifers. Hence the settlers there harvested rainwater from roofs and catchment areas into tanks or underground cisterns which was necessary to provide for household needs.  The farm house where I grew up had a cistern to collect rainwater from the roof and it was built in the 1880’s, before electric pumps were available to pump water. We are not in such dire straits yet, but we can harvest water from roofs to increase water available for garden and landscape use. Rain water that is harvested does not contain chlorine and is soft water, i.e., not containing calcium carbonate, iron or other compounds that make for hard water. Thus it is good water for plants.

There are many sources for barrels and tanks for water harvesting and it is possible to use a connected series of 50 gallon drums to harvest water from rooftops for gardens. Just do a google search on ‘rain barrels’ and you will see lots of choices. I was fortunate to purchase from a bulk water business, three 1000 gallon tanks for water harvesting. They were tanks with flaws that made them no longer fit for potable water, but work fine for collecting rainwater for garden uses. I use one for my entire spring greenhouse plant growing. The other two are used

Eight 50 gallon drums harvest rainwater for vegetable garden seed starts.

for landscape watering. I also have eight 50 gallon drums next to my garden shed which receive water from my garden shed roof. Though a small shed, in a good year I will have 400 gallons of water to use for hand watering of seedlings in my vegetable garden. For more information on water harvesting see:

If you have a gardening related question you can contact the UC Master Gardeners at 209-953-6112. More information can be found on our website:


Posted in Uncategorized | Leave a comment

Be a joiner to enjoy better gardening experiences.

Several years ago, after I had retired, I read a notice in the Linden newspaper that there would be a presentation on ‘Pruning Camellias’ at the local garden club meeting in Linden. I went because I wanted to learn how to prune Camellias. I learned much from expert, Harry Dedini, on pruning Camellias and he later became a friend and advised me on grape pruning as well. After the meeting, I was invited to join the garden club even though they had never had a male member before. Hence, I became the first male in the club and I have benefited greatly from that serendipitous joining.

The National Garden Clubs, of which Linden, Ripon, Lodi, Manteca, Modesto and Stockton Garden Clubs are members, offer many courses that enhance gardening skills. I took a 4 weekend course on Landscape Design that was taught by a Landscape Architect professor from UC Davis. We learned a lot about what Landscape Architects need to know and do to create public and private landscapes and gardens and we learned how to do the same for ourselves or anyone needing design help. I received a Landscape Design Consultant Certificate after the course, but my only consultation was for my own landscape.

My next NGC venture was Flower Show School, a 4 weekend course on flowers which I love and wanted to learn more about. I didn’t realize it in the beginning, but the purpose of this school was to produce flower show judges. So I became an accredited flower show judge after writing a flower show schedule, passing several flower show judging point scoring exercises and a very rigorous final exam. Hence, I became a flower show judge because I like to finish what I start—even though initially I didn’t know what I was getting into.

Subsequently, I have been a member of the Valley Judges Council; a new venue for friendships, learning, service and competition. We exhibit in horticulture and floral design as well as do judging exercises and we also judge at fairs and flower shows, which unfortunately are all too rare these days as it takes a lot of work to stage flower shows. Our own San Joaquin County Fair Adult horticulture show, where I collected many Best of Show ribbons, has apparently gone the way of the Dodo bird.

Recently, I was asked by someone who reads my garden column, “What is the difference between a Master Gardener and a Landscape Design Architect?  Having the Landscape Design course under my belt and being a UC Master Gardener enabled me to answer her question reasonably well. A Landscape Architect has a lot of college training in design and engineering resulting in a Bachelors degree or a Masters degree.  They are not always as knowledgeable about plants as your local nursery person might be, but they know a lot about the physical and material aspects of designing a garden to suit public or private needs.

On the other hand, we who are Master Gardeners come from varied backgrounds and are volunteers helping homeowners and communities with garden problems. We take a rigorous 18 week course through UC Co-operative Extension in a wide range of topics that cover many areas of gardening including basic plant biology and physiology, plant identification, weed management, landscape tree and turf management, as well as aspects of disease and pest identification and management. A Master Gardener is obligated to volunteer 50 hours in the first year after completing the training and to take 12 hours of continuing education.

I applied in 2007 to participate and I almost missed the deadline for the program. I was ambiguous about it, because with 10 acres to manage, I didn’t think I would have much time to devote to helping others garden. However, my wife encouraged me by reminding me that it was something I was well suited for and I had always wanted to teach. My mother was an excellent gardener and my father was a farmer so I grew up with plants and gardens. With a background in biology and ecology, it was relatively easy for me to complete the science based Master Gardener training.

As for time to devote to the Master Garden program, I apparently enjoyed it as I was the second person to complete 1000 volunteer hours. What could be better than working and socializing with fellow gardeners and helping others to enhance their gardening knowledge and skills? Joining can be a life-enhancing experience that I can attest to!  I hope you will find some happy garden joining adventures.

Recently, the deadline for applications for the 2017 UC Master Garden training was closed, but of course late applications will be kept on file until the next training in 2019.

If you have a gardening related question you can contact the UC Master Gardeners at 209-953-6112. More information can be found on our website:

Posted in Uncategorized | Leave a comment

Open Garden Day at the Learning Landscape

As Master Gardeners, we are committed to educating the general public on sustainable horticulture and pest management practices based on traditional, current, and evolving research. One of the ways we do this is through our Learning Landscape demonstration garden located at the San Joaquin UC Master Gardener office.

We will be hosting our first fall Open Garden Day event on Saturday, October 22, from 9:00 a.m. to noon. The garden is located at 2101 E. Earhart Ave., Stockton, at the Robert J. Cabral Agricultural Center just off Arch-Airport Road. This event is free and registration is not required. Light refreshments will be provided. In the case of rain, this event will be cancelled.

The Open Garden Day will feature pruning, irrigation, and planting demonstrations. There will also be a vermicomposting (composting with worms) display as well as some kids’ activities for young garden enthusiasts. Master Gardeners will also be available to talk about the demonstration garden and to answer questions that home gardeners might have about their own gardens. We hope that attendees will be inspired and leave with ideas of things that can be incorporated into their own landscapes.

The Learning Landscape began in 2008 and continues to expand and change. Over the years, Master Gardeners have transformed the originally barren, rocky site into a lively, vibrant garden. A dedicated team of Master Gardeners maintain and improve the garden throughout the year.  Plants are continuously changing as we learn what grows well here and what doesn’t (our battle with rabbits and voles is never-ending).

The goal of our Learning Landscape demonstration garden is to provide the public with research-based, sustainable gardening practices specific to San Joaquin County that are reflective of a variety of environments and gardening experiences. The garden has plants for different needs, including drought tolerance, color, sun or shade exposure, and height. There are ornamental and fruit trees, flowering shrubs, perennial flowers, California natives, vines, and groundcovers. The garden is home to many species of insects, and plants that attract beneficial insects are planted throughout the garden to eliminate the need for chemical pesticide sprays.

The garden also features many sustainable elements. There are water permeable walkways and decomposed granite paths that allow water to infiltrate into the soil. We use weather based irrigation systems that schedule watering as needed based on the current conditions. A drip irrigation system below the mulch allows for uniform watering throughout the garden with minimal loss of water to evaporation. Regular applications of mulch help to conserve water and suppress weeds; the mulch eventually decomposes into organic matter that is beneficial to the soil. Plants that are selected are low water users and are appropriate for the space provided. As a decorative touch, some re-purposed materials have even been turned into garden art.

The garden is composed of 6 distinct but interconnected gardens. Plant identification signs and educational signs tell the story of each garden section. The featured gardens are:

The All-Stars Garden: This section features plants from the UC Davis Arboretum All-Stars program.

The Foliage Garden: A garden with year-round interest that doesn’t depend on flowers.

The Edible Landscape: Demonstrates how to combine food-producing plants with regular landscape plants.

The Mediterranean Garden: Displays plants from the five regions of the world with climates similar to ours, and shows how to combine them for gardens adapted to our area’s climate.

The Pollinator Garden: This section is filled with flowering plants that provide pollen and nectar for pollinators and other beneficial insects. Something is always in bloom!

The California Native Garden: Highlights a variety of garden-worthy native plants adapted to our region.

We invite members of the public to visit the Learning Landscape, and encourage you to visit multiple times to see how the garden’s features change through the seasons. The garden is open 7 days a week, 24 hours a day. Service animals are allowed; pets are not.

For information on scheduling a private tour for your group or organization, call our helpline at (209) 953-6112. For information about other Master Gardener workshops and events, call our number or visit the UCCE Master Gardeners of San Joaquin County website at






Posted in Uncategorized | Leave a comment

The science behind colorful fall foliage

Crisp cool air and shorter daylight hours are harbingers of one of Nature’s most spectacular gifts: leaves in all their autumn glory. Fall is a welcome time of transition, when hot temperatures subside and foliage slowly transitions from the vibrant greens of summer to hues such as yellow, gold, orange, red, burgundy, and purple.

A flaming red Liquidambar tree (Photo by Kathy Ikeda)

Although fall leaves might resemble an array of warm-colored paint samples in a hardware store, the beauty of their colors comes from within. Plants contain compounds called pigments in their cells. Each pigment absorbs specific wavelengths of light; the light reflected back is what we perceive as its color. There are several main classes of plant pigments:

Chlorophylls. With a name derived from the Greek words for “green” and “leaf,” these pigments give plants their typical color and fuel the process of photosynthesis. Plants produce chlorophyll when they’re actively growing, but with the onset of fall, a plant’s metabolism slows and chlorophyll production halts; this allows other plant pigments to be visible.

Xanthophylls and carotenoids. These closely-related compounds are responsible for the yellow and orange colors in plants. Some specific examples are carotene in carrots (what else?), lutein in yellow fruits and vegetables, and lycopene in red tomatoes. Such pigments are present in leaves year-round, but are usually hidden by the more plentiful chlorophylls.

Anthocyanins. These pigments also have a Greek-based name, one that means “flower blue.” Their color is pH-dependent and can range from purple to blue to red. Anthocyanins are present in the tissues of all higher plants. Unlike other pigments, they’re produced in leaves only at the end of summer when chlorophyll and other sugars are broken down in the presence of bright light. (That’s why the reddest leaves and fruits such as strawberries are the ones with the most sun exposure.)

Vibrant leaves of a Liquidambar tree (Photo by Kathy Ikeda)














Most plants with vivid fall color are deciduous, meaning that they lose their leaves during the dormant season. There’s a reason for this: the process that halts a plant’s chlorophyll production during the shorter days of fall is the same one that helps conserve a plant’s energy reserves and shuts off the flow of nutrients into the leaves.

California can’t match the stunning fall foliage displays of the New England states, but there are plenty of plant species that can be used to add seasonal color to our landscapes. Here are a few outstanding plant selections for our area:

  • Chinese pistache (Pistacia chinensis): This tree performs spectacularly in our climate, with attractive leaves that turn vivid hues of red and orange before falling.
  • Maidenhair tree (Ginkgo biloba): This slow-growing tree is known for its rich golden-yellow fall foliage, which drops en masse when spent. Choose a non-fruiting specimen.
  • American sweet gum (Liquidambar styraciflua): The messy “stickerball” seedpods and invasive roots of this tree can be a nuisance, but its multicolored fall foliage is stunning, especially in California-developed varieties such as ‘Palo Alto,” ‘Festival,’ or ‘Burgundy.’
  • Japanese maple (Acer japonicum): There are countless named varieties of these beautiful trees; their delicate leaves have fall colors in a wide spectrum of warm hues.
  • Persimmon (Diospiros kaki): This tree’s leathery leaves turn yellow and orange, and the bright orange fruit persists as ornaments on bare branches.
  • Smoketree/smokebush (Cotinus coggygria): A small tree or large shrub. Some varieties have unusually colored mature foliage (lime green in ‘Ancot;’ burgundy in ‘Royal Purple’), but the leaves of nearly all varieties turn yellow-orange, orange-red, or scarlet in autumn.
  • Heavenly bamboo (Nandina domestica): This evergreen shrub has many cultivars, but some (including ‘Firepower’) develop pretty red leaf color in response to cold exposure.

October and November are best months to purchase plants for fall color. Individual trees or shrubs of the same species can differ greatly in the colors they produce — one plant might be intensely colored, while another might only produce a subdued display. Shop for plants during their period of peak color to be certain of selecting your favorite palette. Place them in the ground immediately so that their roots can grow in still-warm autumn soil, then sit back and enjoy!

For gardening related questions, call the UC Master Gardener office at 209-953-6112, or use our website:


Posted in Uncategorized | Leave a comment

Diagnosing Plant Problems Is Key to Success

Blossom end rot on tomatoes resembles a disease, but is actually caused by calcium deficiency.

Every gardener encounters problems at some point. Nature is our host, greeting gardeners’ hubris with humble pie served by drought, disease, and pest invasions. In the old days one could blame ignorance for missteps in managing pests and diseases; fortunately, our increased understanding of nature’s rules has allowed us to move beyond “spray and pray” and into the role of conscientious gardeners.

Becoming conscientious is not always easy. When we see sad plants, our automatic reaction may be to apply one or both of the supposedly universal panaceas: water and chemicals. Taking the time to diagnose plant ailments can require patience and perseverance, but understanding why problems happen increases your chances of success and prevents future mistakes.

Reducing the misuse and overuse of pesticides and herbicides is another advantage to accurate diagnoses of plant problems. If you think your tomato has a fungal disease and it’s actually suffering from a calcium deficiency (blossom end rot), spraying fungicide is ineffective, a waste of money, and introduces potentially harmful chemicals into your garden and food.

Solving plant problems means accepting the garden as an ecology with numerous interconnected elements to consider. A classic example is black sooty mold, a leaf-dwelling fungus resembling its name. Sooty mold grows on the sugary secretions left behind by aphids, which are placed and protected by ants, which harvest the sugar for food. Fungicide won’t help much if the cause (ants and aphids) sticks around. In this example, an ecological approach would call for eliminating the ants and spraying the aphids off the plant with water, thereby reducing the sooty mold’s “habitat.”

Knowing why plants droop or get eaten can seem overwhelming at first, and the list of potential causes is sizable. It might ease your mind to know that 90% of plant problems are water-related, either directly or indirectly. The vast majority of gardeners overwater, saturating the soil and creating an anaerobic environment that starves roots of oxygen. Another common mistake is watering a little bit everyday, resulting in drought-prone shallow roots.

A good place to start is identifying the plant species. Plants typically have associated problems, and knowing the species can help you narrow down the causes and management strategy. If you need help identifying your plant, you can go to an independent nursery or contact your local Master Gardener program (a free service). The UC Integrated Pest Management program is an excellent resource, offering visuals of different plant problems and least toxic management strategies. Their website can be found at

Where you go from there is dependent upon the situation, but factors to consider are the time of year, the weather, diseases and pests the plant is susceptible to, and where on the plant the problem is occurring (all over or confined to one part of the plant). You might also think about non-biological causes, such as accidental pesticide exposure, “blade-itis” (damage by mowers, weed whackers), or burns from a heat-reflecting wall. A final tip is to always check the soil if in doubt about whether to irrigate. A drooping plant can be a sign of too much water or not enough, and the top 1”-2” of soil may be dry even if there is plenty of moisture below.

If the UC Integrated Pest Management website seems overwhelming, try their diagnostic tool at Providing information such as the plant species, which parts of the plant are affected, and the type of damage, allows the diagnostic tool to identify one or more causes. This makes a good starting point, especially for those who are new to identifying plant problems.

If you have a gardening related question you can contact the UC Master Gardeners at 209-953-6112. More information can be found on our website at

Posted in Uncategorized | Leave a comment

Autumn garden chore time is here

An enjoyable chore-cutting Dahlia bouquets. Lee Miller photo.

An enjoyable chore-cutting Dahlia bouquets. Lee Miller photo.

It is time for fall plantings of all kinds of vegetables. In August, I started lettuce, fennel and onion seeds in flats and I also direct seeded beets, collard greens, lettuce, fennel, turnips, kale, carrots and Kohlrabi. Bok choy and Chinese cabbage are other good fall vegetables. The broccoli, cauliflower and cabbages I had planted in flats in early July had more failures than successes, so I replanted them and recently transplanted them to the garden. I hope they can make a crop because timing is important. Get them started too late and they don’t always grow sufficiently before cold weather to produce a crop. Last year the plants I bought at the nursery did not do well because they apparently were started from seed too late. However, it is worth the gamble to grow a winter garden. Garlic and peas should be planted in early October and onion sets around November 1 or earlier if available. California is a paradise for gardeners because vegetables can be grown year around.

Fall is always the best time to plant shrubs and landscape trees. The cool winter temperatures and rains will give plants time to grow roots and become established, before the challenging heat of next summer. If you love fall colors of red or gold on your trees then some good ones to plant are: Chinese pistache, Gingko, Tupelo, scarlet oak, red oak, Japanese maple, red maple, crepe myrtle or redbud.  It is a good idea to make sure that any mature trees will fit into your landscape space and not be a problem for service lines.  PG&E has a good tree guide book for the right tree in the right place that you can order free from PG&E:

It is also time to plant bulbs, perennials, annuals for winter/spring blooms. With cooler weather, you can plant perennials such as: foxglove, Geum, Penstemon, Salvia, yarrow, Delphinium, Coreopsis Gaillardia, and Campanula and annuals such as: snapdragons, larkspur, ornamental cabbage and kale, Iceland poppies, primrose and stock.  Keep soil moist before the rains start for success and optimal growth. Order your spring blooming bulbs early for best selection and to get them in time for October planting. There are early, mid-season and late-season choices in most bulbs so you can extend bloom enjoyment by careful selection. Narcissus come in a wide variety of shapes and colors and is my favorite because, once established, they come back abundantly every spring; unlike tulips which are generally planted as an annual. Some other choices are: anemone, calla, freesia, Hyacinth, Muscari, and Dutch iris

Prune any low branches from your citrus to discourage fungus infection on the fruit. Cut off branches lower than 18-24 inches above the soil and clean up fallen leaves, old fruit or other organic matter and then mulch with wood chips or bark to keep fungus spores from infecting low hanging fruit when it rains.

Fall is a good time to divide perennials if they are overcrowded. They will grow and bloom better when not crowded. Ornamental grasses Iris, Shasta daisies, Solomon’s seal, yarrow, daylilies; Agapanthus and cannas are just a few which need periodic division. They can be dug up with a spading fork or shovel and then divided with a sharp knife, saw or spade. Replant ASAP or give some extras to friends or neighbors.  Add compost to make up for any lost soil volume and discard any unhealthy plants. For more tips on division of plants see:

Roses will be coming into the fall bloom period although if you dead-headed them frequently you likely enjoyed some roses all through the summer. Final feeding for roses should be in October and it is best to give it either compost or 0-10-10 fertilizer as nitrogen will encourage tender, frost damage-prone shoots. Renew the mulch for winter and avoid fertilizing again until spring.

After two hours work---A full wheel barrow of weed trees and Camellia trimmings. Lee Miller photo.

One of my garden rules is to ‘pay attention’. When you don’t ‘pay attention’ plants can die for lack of water, weeds can take over; lots of things can go wrong. One recent Sunday morning I decided I needed to trim back a Camelia from the doorway to my wine cellar, because I would soon be opening it to bottle wine. As I started trimming, I noticed that there were many seedling trees growing under the Camellias. I spent two hours digging out walnut, pecan, privot, bay, Virginia creeper, and Algerian ivy seedlings from under the Camellias. Some had obviously been there for a long time, but I hadn’t payed attention. Some chores can come your way when you are not even looking for them. I went on to prune dead wood and stray branches from the Camellias and ended up with a wheel barrel of clean up stuff for my unscheduled morning’s work. Gardening often can surprise like this, it seems. Happy autumn gardening!

If you have a gardening related question you can contact the UC Master Gardeners at 209-953-6112. More information can be found on our website:

Posted in Uncategorized | Leave a comment
  • Blog Authors

    Lee Miller

    Lee Miller is a University of Delaware graduate and retired fisheries biologist, he gardens on 10 acres and makes wine each year with the help of a cadre of friends. However, his first love is gardening and he grows various fruit trees, heirloom ... Read Full

    Marcy Sousa

    Marcy Sousa is the San Joaquin County UC Master Gardener Program Coordinator. She is a Stockton native and enjoys teaching others about gardening. She has her bachelors from Stanislaus State in Permaculture. She has been with the program since 2007. Read Full

    Nadia Zane

    Nadia Zane is a UC Master Gardener, a landscape designer and Stockton native. She has a fondness for California native plants and sustainable landscaping, which she utilizes in her work for Native Beauty Garden Design. She is a member of the CA ... Read Full
  • Categories

  • Archives