By T. Eric Nightingale, U.C Master Gardener of Napa County
There is nothing quite like walking through, or relaxing near, one's own garden. Gazing upon the plants that have thrived and bloomed, the result of hard work and tender care, is a singular experience. Only a gardener can truly know the special joy that it brings.
There is another experience unique to gardeners. It is when, as they let their eyes wander over the delicate curves and rich colors of a plant, something catches their eye. It may be a strange color or an odd pattern. Perhaps a flicker of movement in the corner of their eye.
This is the time when the gardener's lip curls slightly into a sneer and they bend down, squinting into the foliage. Then they see it, something that shouldn't be. Something uninvited. Then, an eyebrow raised, they wonder “what exactly, is that?”
Pest intrusion is an undesired, yet unavoidable, part of having a garden. Some plants are more susceptible than others (pests usually want to eat the same things we do), but there is no guaranteed way to prevent contamination. Even the most dutiful gardeners will find themselves facing the task of extermination. First, though, comes the challenge of identification.
Correctly identifying a garden pest is an important part of Integrated Pest Management. Yes, a liberal spray of general insecticide would solve the immediate problem. This action, though, would only open the door for many other, perhaps even more serious, threats.
The best approach is to identify the intruder and approach it with a personalized attack. Looking down upon some anonymous, multi-legged critter, you may find it difficult to know where to begin. I always begin my reminding myself that, while creepy, crawly, and generally unattractive, the creature may not be a threat.
Many of the bugs in our gardens are neutral, and some are even beneficial. I assume them “innocent until proven guilty.” With this in mind, I begin my investigation.
What type of plant are they on? While some pests attack a range of plants, some only target specific ones. Often the answer to this question will narrow the range of possibilities considerably.
Many books and websites detail common garden pests, but my first stop is always the University of California Integrated Pest Management website (www.ipm.ucanr.edu). I find the type of plant I am working to save and am presented with a list, complete with pictures, of the organisms that attack it. Those who are patient, or generally curious, can read through the various entries until one seems to match the invader. To make the process quicker, I recommend noting a few key attributes of the pest in question.
The first thing I always look for is plant damage. Is the pest chewing on the leaves, sucking out its juices, or boring into it? Sometimes the damage is the only clue I have to work with, as in the case of nocturnal pests such as snails and slugs.
Sometimes it can be difficult to tell pest damage from disease damage, so keep an open mind if no pests are present. The type of damage indicates how the pest feeds, a useful clue to identification.
When inspecting the pest itself, I start with the basics. Sometimes different bugs have similar coloring or markings, making it difficult to tell them apart from memory, when away from the garden. Next, I note the number of legs. A handheld magnifying lens makes this easier and is arguably the most useful tool a gardener can own.
If the bug has eight legs, it is an arachnid. Six legs, it's an insect. If I have an arachnid on my hands, I make very sure it is a pest and not a spider. Spiders are one of the most beneficial creatures in our gardens, consuming enormous amounts of bugs each year. As much as possible, I leave them to their work.
If it is not a spider, chances are it is a mite and will require appropriate treatment. A six-legged invader requires further investigation as the options are more numerous.
At this point, it helps to note other parts of the pest. Does it have wings? Does it have large jaws, pinchers or antennae? Is it creating or secreting any substances? I have occasionally overlooked these telltale characteristics, figuring that a creepy bug would, of course, have some weird features.
Armed with facts from my detailed investigation, I often find my research goes quickly and smoothly. Once the pest is identified, treatment becomes obvious and, in some cases, not even necessary. A few pests cause minimal damage in small numbers and depart the garden on their own. In these situations, it would be a waste of time and money to apply an insecticide.
Other times all that is required is some easy cleaning or pruning. If I need to take more drastic action, at least I know my enemy.
When I struggle to address my garden problems on my own., I turn to the U.C. Master Gardeners of Napa County help desk (hours below). The friendly and knowledgeable people there are always excited to help solve a bug mystery.
Workshop: U. C. Master Gardeners of Napa County will conduct a workshop on “Make Room for Salvias” on Saturday, April 21, from 9:30 a.m. to 11:30 a.m., at the University of California Cooperative Extension office, 1710 Soscol Avenue, Napa. Every gardener should be able to find a salvia just right for that little (or big) space. Salvias are long-lasting, attract butterflies and pollinators and have attractive foliage. Learn how to select and care for these versatile plants.Online registration (credit card only);Mail-in/Walk-in registration (cash or check only)
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
Peter Jacobsen's renowned Yountville orchard had humble beginnings. “We had no qualifications except that we had no fear of dirt,” says Jacobsen, a dentist with a San Francisco practice.
I find his simple statement both comical and inspiring. When Peter and his wife, Gwenny, bought their Yountville home, they had no plans to grow food. But the home came with land that had already been partially prepared and gardened. One thing led to another, and today the fruits and vegetables they grow are prized by many of the valley's premier chefs.
Not only does Peter have a mouth-watering vegetable garden, but he also tends an impressive collection of fruit trees. I was fortunate enough to visit and was fascinated by his mulberry trees.
We don't see many mulberry trees in Napa Valley, yet they thrive in our climate and are fairly drought tolerant. The fruit looks something like an elongated blackberry. The tree itself has attractive, hanging branches that make it a handsome addition to a garden.
Mulberries are easy to harvest and delicious. As I learned from Peter, the trees produce fruit only on new growth. As a result, you can achieve higher yields by pruning after harvest and pruning to maximize branching.
As we walked through his orchard, Peter picked several stone fruits that I had never tasted. My two favorites were the Damson and Mirabelle plums.
The Damson plum is the most beautiful plum I have ever encountered. It looks something like a giant blueberry. The flavor is slightly astringent, but it is a great plum for cooking.
Grown throughout western Europe, the Mirabelle plum is red or yellow and contains white flesh. It is tasty when fresh but is most often made into wine or jam. Both the Damson and Mirabelle plum trees are also often used in Europe as hedges or windbreaks. They are sturdy trees and can protect their weaker neighbors.
Interestingly, Peter advises against attempting to grow cherries, apricots or avocados in the Napa Valley. In his opinion, these trees are incompatible with the local climate. This was a relief to me, as it assuaged my guilt over the death of my avocado tree last year.
The Jacobsen orchard experiences the same challenges as the rest of us; it is not immune to pests and diseases. The Jacobsens practice Integrated Pest Management, and the results are apparent.
While both fire blight and peach-leaf curl have hit some of his trees, Peter responds with prudence. I asked if he recommends copper fungicide for treating the leaf curl, and he said he uses it sparingly, worried about copper buildup in the soil. He is willing to tolerate some peach-leaf curl as it does not impede fruit production.
On the other hand, Peter does have a reason to battle peach-leaf curl. During my visit, he plucked peach leaf and crumpled it in his hand. What a surprise to have the strong smell of almonds fill my nose. Peter's chef-customers are currently using peach leaves to infuse dishes with this aroma.
The Jacobsens use no chemical fertilizer in their orchard but instead plant cover crops around the trees. Planting peas, mustard and clover helps to return nitrogen and other nutrients to the soil. The thick coverage also leaves little room for weeds.
As I learned from Peter, all we need to grow a garden is a little knowledge and a lot of motivation. As humans, we live in a structured environment, filled with things that we have designed and built. I think it's important to remember that plants want to grow, that they need us much less than we need them.
This realization can take some of the stress and doubt out of gardening. If you know your land, what grows well there and what makes it thrive, you are halfway to your goal. The only other thing you need is a willingness to get a little dirty.
Workshop: The UC Master Gardeners of Napa County will hold a workshop on “Toxic and Carnivorous Plants and Mushroom Kits” on Saturday, October 28, from 9:30 a.m. to 11:30 a.m., at University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Foxglove. Lily-of-the-valley. Wisteria. These common plants and others are toxic. Who knew? Sundew. Venus flytrap. Pitcher plant. They're carnivorous. While we would not touch a mushroom in the garden, growing edible fungi from kits is easy and neither toxic nor carnivorous. Explore the fascinating properties that plants have to protect them. Online registration (credit card only);
Mail-in registration (check only or drop off cash payment)
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
By Okhoo Hanes, U. C. Master Gardener of Napa County
If you are a home gardener in Napa Valley, you can successfully grow olive trees. Olives are one of the most popular trees in the valley, and with a few pointers extrapolated from University of California research and other sources, you can enjoy their beauty in your own landscape.
Olive trees are evergreen and both ornamental and edible. They are relatively easy to grow and maintain, suitable for the fairly arid Mediterranean-type climate of the Napa Valley. They are not fussy about fertilizer, needing only nitrogen. Nor are they water hogs. Once established, they take to xeriscaping or even no watering at all, cutting down on irrigation chores.
The olive tree's silver foliage, smallish, oblong leaves and graceful branches add interest to any landscape, large or small, including container gardens.
But olive trees are not without drawbacks. For one, growing your own olives for pressing or curing may cost more than you expected. In all likelihood, your olive oil or cured olives will cost you more than store-bought olive oil or olives and take more care and time than you imagined. Nonetheless, you may decide that the experience and satisfaction of growing and producing healthy food of your own is worth the expense and the journey.
David Layland, a U. C. Master Gardener of Napa County and past president of the group, has had an experience with olives that is probably typical. He planted nine olive trees primarily for landscaping purposes. Fruit production was almost incidental. The laborious harvesting required the help of friends.
Layland encountered unexpected costs for cultivation, care and maintenance, including the unavoidable pest problems, most notably the olive fruit fly. Then there's the inevitable reality that friends move or fade away over time. Still, he is happy to be taking the olive tree journey.
The nutritional virtues of extra-virgin olive oil, a heart-healthy monounsaturated oil and antioxidant, have been widely touted. But research hasn't shown whether there is any discernible difference in the health benefits between local and imported oils. What is certain is that extra virgin olive oil contains more antioxidant polyphenols than virgin olive oil and is a healthier choice.
For pressing or curing, available varieties for home gardeners include Mission, true Picholine (not Redding Picholine), Majestic Beauty and Manzanillo. Five-gallon plants provide a good head start, but one-gallon plants, if available, are considerably less expensive. The Kalamata variety is excellent for brining or salt-curing.
Fruitless varieties (Little Ollie, Wilsonii and Swan Hill) are better choices for those who are not interested in food production. Alternatively, you can minimize fruit formation by applying a plant-growth regulator (available at garden centers) or using a high-pressure hose during bloom. But these methods are not reliable, so fruitless varieties are a more sensible choice. Fruitless varieties also produce fewer allergens.
Full-size olive trees reach 25 to 30 feet in height and can be just as wide. They can take heavy pruning but consider the available space before you plant. University of California research suggests that more space between the trees leads to better fruit production. Although 16 to 20 feet is recommended, such generous spacing may not be practical in a home orchard.
If you have limited space, consider a dwarf variety such as Skylark Dwarf, which tops out at about 16 feet. Another method for selecting a suitable variety is by tasting oil samples at farmers' markets or retail stores.
Olive trees need about 200 hours of winter chill. Some require a pollenizer variety, such as Pendolino, for good fruit production.
Fresh olives are too bitter to eat without curing, but they can be pressed for oil. If you don't have enough olives to meet the minimum at a commercial pressing facility, such as Jacuzzi in Sonoma, you can combine your harvest with others to meet the minimum. The olives must show no sign of pest damage. For curing, follow the step-by-step instructions in UCANR Publication 8267 (“Olives: Safe Method for Home Pickling”). You can get a copy of this publication at the Master Gardener office (address below).
Napa Valley olive trees have suffered from infestations of the olive fruit fly, which damages the fruit. Trapping, seasonal spraying, good sanitation (picking up all fallen fruit) and biological controls are among the tactics growers employ. Research is ongoing and, in the meantime, Napa County home gardeners should contact the Master Gardeners office about the current recommended methods for fruit-fly control.
And consult this information from UC Integrated Pest Management:
http://ipm.ucanr.edu/PMG/PESTNOTES/pn74112.html
Free Tree Walk: U. C. Master Gardeners of Napa County will host a guided tree walk of Fuller Park, 560 Jefferson, in Napa, on Monday, July 10, from 10 a.m. to noon.Enjoy a fun, informational stroll through the park, learning about its history and 41 different trees on site. Wear comfortable shoes. Restrooms are available and handicap accessible. The book Trees to Know in Napa Valley will be available for $15 each (cash or check only).
To register, call 707-253-4221. Walk-ins are welcome, but you are guaranteed to receive a complimentary map and additional information if you register at least 48 hours in advance.
Workshop: U. C. Master Gardeners of Napa County will conduct a workshop on “Growing Olives” on Saturday, July 22, from 9:30 a.m. to 11:30 a.m., at Big Dog Ranch, 1020 Congress Valley Road, Napa. Got an olive tree? Want to grow one? Learn the details for each season's necessary activity for a healthy and tasty harvest. Controlling olive pests is also on the agenda. Online registration (credit card only);
Mail-in registration (check only or drop off cash payment).
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
Sowbugs! Pillbugs! Rolly-pollies! UC Master Gardener, Penny Pawl, gives us facts about these creatures, which are not insects and are not necessarily garden bad guys! And as always, UC IPM has some information for gardeners about sowbugs and pillbugs:
http://ipm.ucanr.edu/PMG/GARDEN/FRUIT/PESTS/sowbugs.html
Now, from Penny Pawl.
One summer when I was about 10 years old, I had two farms. One was a lizard farm, with a variety of lizards that I had collected and put in a big box. I had alligator lizards and blue bellies. That adventure ended when a lizard bit my mother on the finger. Goodbye, lizard farm.
I also had a pill bug farm. I put rocks in the middle of a large dish filled with water and put the pill bugs on their individual islands. That was when I first noticed that pill bugs carry their babies between their legs and under their shells. In both cases, I had not made arrangements to feed my pets and can't remember even thinking about that. I also raised tadpoles next to my bed and had a horny toad living in my closet.
I am now a Master Gardener and am still friends with lizards and pill bugs. Also known as roly-poly, sow bugs and wood louse, pill bugs have moved in to live with my worms and at times seem to outnumber them.
When I first started worm composting, the University of California published an article that said the manure or droppings of these creatures was just as nutritious for plants as worms castings. Worm castings are the worm “gold” you read about. Maybe you have purchased some to fertilize your plants. Worms eat 90 percent of the decaying plant material that you give them. Their resulting manure is a mild fertilizer with all the trace elements. Pill bugs eat the same things that worms do.
Pills bugs are not actually bugs. They are crustaceans, members of the same family as lobsters and crabs. They breathe through gills.
They live in dark, moist areas and eat decaying material such as dried leaves, tea bags and banana peels. Occasionally they feed on the tender leaves of emerging plants and seedlings. For this reason, they are considered garden pests. But in the right place, they are not pests.
Some types of pill bugs cannot roll up into a ball when trying to defend their selves. These are the sow bugs. They are built a little differently in the shell area. Also, if you look carefully, you can see their tails. When they molt, only half of the shell comes off initially. A few days later, the other half comes off. These shells look bluish rather than brown.
Pill bugs do not need a male to reproduce. They are self-fertile. The eggs take three to nine weeks to hatch, and a pill bug can lay eggs up to three times a year. The young spend several days in the mother's pouch and then go out on their own.
A pill bug's predators are anything larger: frogs, toads, lizards and small mammals.
If you think your seedlings and young plants are under attack by these little creatures, then make sure you water in the morning so the soil surface is dry at night. That's when pill bugs go out looking for their next meal. I read that you can trap them with a half cantaloupe, but I have found that quail and other birds are usually the ones nibbling on my seedlings.
Workshop: U. C. Master Food Preservers will teach a workshop on “Pickling and Fermenting” on Friday, July 14, from 10 a.m. to noon, at University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Learn the basics of pickling and fermenting, understand the cautions involved in home food preservation, watch a demonstration of each process and discuss recipes easily managed by the home cook. THIS WORKSHOP IS FULL, AND REGISTRATION IS CLOSED.
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
They have been waiting patiently, and now their time has come. Creatures that love the wet weather are finally able to come out and do what they do best: make you miserable.
For many Napa Valley gardeners, this time of year can be frustrating. We have been watching our plants prosper under relatively consistent conditions for months, then the weather shifts. It starts to rain, and if we're lucky, it rains a lot.
The wet weather is a game-changer. Having grown up in the damp Pacific Northwest, I know this game well. Particularly familiar to me is the battle against mold, mildew and other fungi.
These plagues seem to come from nowhere and not reveal their presence until they are such a problem as to make you question your commitment to gardening. Only the truly devoted (or crazy) will find themselves scraping white, stringy fungus from a clogged planter box on a dark and rainy afternoon.
However, there are steps you can take to minimize these winter challenges.
If you have plants in containers, check the drainage. A container that was perfect a few weeks ago may now be draining too slowly. It is disheartening to see a formerly healthy plant succumb to root rot from standing water. Remove any debris that may be preventing drainage, or move the container to a location shielded from the rain.
Inspect your irrigation system and be sure you are not overwatering. Watering schedules probably need to be adjusted to avoid flooding the lawn.
Plants suffering from overwatering can look deceptively similar to those suffering from under-watering. I have made this mistake before and spent a good deal of time angry with myself for drowning an already saturated plant. Investigate the cause of the damage you see before applying a remedy.
Do a detailed inspection of landscape plants, especially deciduous trees and shrubs. The lack of foliage will make any pests and damage much easier to locate and identify.
Some pests, such as scale, will soon be in their dormant, over-wintering, phase. During this stage they are more vulnerable to applications of horticultural oil. They are not breeding either, so you need not worry about missing their offspring when you spray.
Many plants have well-known pests, and an experienced gardener will recognize the culprit from the damage. The University of California's Integrated Pest Management website (http://ipm.ucanr.edu/) is a useful resource. You can enter the name of a plant and see a list of possible pests and diseases, often with photos. Should you see damage that you can't identify, take a photo and email it to the Master Gardener Help Desk (information below). You can also bring the damaged plant parts to the Help Desk and a Master Gardener will help you identify and manage the problem.
At this time of year, many people have unwanted visitors in their homes, and I don't mean the in-laws. The best way to manage rodents and ants in your home is to deny them access. Inspect the exterior of your home for possible entry points that may have developed over the summer.
Just because you haven't had problems in recent months does not guarantee future security. A small hole that pests ignored while they were comfortable outside can quickly become a superhighway during cold and wet weather. Fill holes with wire mesh or other strong materials that pests cannot chew or dig through.
If you are unable to seal a hole used by small insects, try blocking them with a line of diatomaceous earth. A powder made of ground silica, this product is safe for use around the home and has a high success rate. When it comes to your in-laws, however, I have no advice. You will have to figure that out for yourself.
Workshop: U. C. Master Gardeners of Napa County will host a workshop on “Rose Pruning” on Saturday, January 7, from 10 a.m. to noon, at University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Certified rosarian Lynne Andresen and other Master Gardener rose enthusiasts will demonstrate and explain proper pruning techniques and review rose types, common rose disorders and routine maintenance. Online registration (credit card only); Mail-in registration (check only or drop off cash payment).
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. U. C. Master Gardeners of Napa County ( http://ucanr.edu/ucmgnapa/) are available to answer gardening questions in person or by phone, Monday, Wednesday and Friday, 9 a.m. to Noon, at the U. C. Cooperative Extension office, 1710 Soscol Avenue, Suite 4, Napa, 707-253-4143, or from outside City of Napa toll-free at 877-279-3065. Or e-mail your garden questions by following the guidelines on our web site. Click on Napa, then on Have Garden Questions? Find us on Facebook under UC Master Gardeners of Napa County.
