By T. Eric Nightingale, UC Master Gardener of Napa County

The heat is on and our gardens are bursting with delightful treats. If you are like many people in the valley, you are looking at your upcoming vegetable harvest and wondering what you are going to do with it all.

Many people give their excess fruits and vegetables to friends and neighbors and do not think about preserving them for later use. In the past, my personal approach can be summed up as, "I hope you like salad, because that's all we're eating this month.” Not very exciting. 

As I've learned, preserving fruits and vegetables is not difficult. The basic canning process is mostly a matter of properly cleaning, heating and sealing your containers to be sure the preserves stay safe. If you are into gadgets, this is the hobby for you. Although all you really need are jars, a large pot, and some jar tongs, there are many tools and appliances designed to improve the efficiency and ease of preserving. 

You can preserve just about anything in a jar, and the results are definitely worth the effort. There is nothing quite like eating home-grown strawberries as a harsh winter gale blows against your window.

Possibly the most familiar preserves are the ones made with berries and tomatoes. While jam and pasta sauce are easily in my top 10 favorite foods, I can't get overly excited about making them. However, I am particularly interested in "ready-to-eat" preserves that you can use directly from the jar, no further cooking required. My chef/sommelier wife, Andreya, had some recommendations. 

"I particularly like summer squash conserva," she told me. "You can eat it with burrata, sea salt, olive oil and a little basil. It's a tasty snack on bread or crackers as well."

To make summer squash conserva, you cut the squash into bite-sized pieces, then cover it with a hot herb-infused mixture of one part red wine vinegar to two parts olive oil. The slightly softened but still crunchy squash can be tossed into a green or grain salad, or combined with fresh cucumbers and peppers from your garden to enjoy with hummus and grilled pita. 

A second option for summer squash is to roast it with wine, garlic and olive oil until soft, then puree it and jar it. When reheated it makes a nice alternative to tomato sauce for your pasta or pizza. 

Another enticing suggestion my wife offered was for cherries pickled with hibiscus, red wine vinegar, sugar, tarragon and star anise. This idea threw me off at first, as cherries did not seem compatible with the flavors I associate with pickling. I have since discovered that they add a delicious tart sweetness to a dish like salmon with ginger forbidden rice. Pickled cherries are also a nice accompaniment to your favorite cheeses and particularly delicious with grilled halloumi, honey and fresh mint.

If you are growing eggplants, save some for baba ganoush, the Middle Eastern appetizer made with roasted eggplant, olive oil and tahini.

Finally, don't disregard your herbs. Instead of composting them at the end of the season, cut and dry them for later use. You can do this with a dehydrator, or just hang them in bundles upside-down in a dry location. Once dried, they can be stored separately or blended into personalized seasonings. A package of your personal herb blend is a gift that anyone would be happy to receive.

Some flowers, like calendula, also lend themselves to drying. Use dried calendula blossoms to add a vibrant yellow-orange color to a fall or winter dish.

There are many other ways to preserve your hard-earned summer bounty and some great resources online. If you are feeling tired of a favorite vegetable, it's time to experiment. You may discover that preserving it reinvigorates your interest.

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.

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.

In recent years, the plight of the honeybee has made international headlines due to alarming colony losses. When many folks hear the term pollinator, the honeybee quickly comes to mind. While honeybees are indeed an invaluable pollinator resource, there are many other pollinator species with interesting stories.

For example, Syrphid flies (Syrphidae) are intriguing garden guests. Also known as hoverflies, they are contenders for second place after native bees as important pollinators. In fact, many look remarkably like bees and wasps and reveal their identity only upon close inspection.

Attracting hoverflies to your garden has an added benefit: many of their larvae are important in controlling aphids. Peaches, plums raspberries and strawberries are just a few of the edible crops they pollinate.

Moths are another important pollinator. When bees retire at the end of the day, many species of moths take over the night shift. With a preference for light-colored and fragrant flowers, they are top-notch pollinators for gardenias, tobacco and morning glory. 

Many moth species rival butterflies when it comes to beautiful markings. To help keep them in your garden, reduce or eliminate unnecessary bright lights, which can disorient them.

Bananas, mangos and peaches are a small sample of fruits that bats might pollinate. Like moths, bats work the night shift. Several species of pollinator bats inhabit the southwestern

U. S. and Mexico, and some agave and California desert cacti depend on them for pollination. 

The bats in Napa County are mostly insect-eating species. Some can easily consume several hundred insects, including mosquitos, in an hour.

Few people know that mosquitos are also a pollinator species. We malign them for spreading disease and causing itchy bites, but actually only the female bites. Males drink nectar—as do females—and transfer pollen in the process.

Wasps are critical pollinators for some fig trees, which are popular in our mild Mediterranean climate. While some modern fig cultivars can produce fruit without wasps, traditionally the fig wasp is the main pollinator. The female wasp lays her eggs in what will become the fruit and in doing so transfers pollen she has collected. She then dies and is resorbed by the fruit as it matures.

One other pollinator species often gets overlooked: humans. Yes, in many instances, we do the job by hand. Vanilla is perhaps the best-known example. However, some plants grown in greenhouses—such as tomatoes—are gently touched with an electric toothbrush to simulate the “buzz” pollination of bumblebees and release large amounts of pollen. This is an excellent way to boost production in your own garden. 

Giant pumpkins—or any squash for that matter—can also be hand pollinated. While the method is a bit more involved, hand pollination can also be used to keep desired strains pure or to increase the likelihood of getting a crop at all. 

Beetles, lizards, ants and even snails and slugs are all known pollinators, among many others. Planting different species of plants and growing flowers with different bloom periods can provide food and habitat for these essential creatures. 

Also, planting natives and flowers known for nectar or pollen is a good strategy for attracting pollinators. Decreasing or eliminating your use of pesticides will also help. With summer weather in full swing, take a closer look at your garden. You might just find a few of these pollinators are already present.

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.

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.

The drought is now officially over and Yosemite National Park is in its full glory with profuse waterfalls. But we all know that California's water resources are fragile.

In the garden, plants cannot grow without sun and water. We have no control over daily sunshine, but we can influence water supply somewhat by making a self-irrigating pot. Such a container provides some assurance that your plants are getting the water they need with less labor on your part.

You can buy ornamental pots for gardening, but if you are growing edibles seriously at home, you may want less expensive, larger-capacity alternatives. Some stores do carry self-irrigating trough containers intended for vegetable growing, but they can be costly. You can create your own with less investment.

Self-irrigating pots and raised beds reduce watering needs dramatically, sometimes to zero in locales that get rain. You do not need to set up a drip-irrigation system. In Napa Valley's Mediterranean-type climate, a self-irrigation pot (SIP) system may still require occasional watering, but depending on your micro-climate, once every few weeks or once a month may be sufficient. In short, a SIP system simplifies your life and reduces watering chores drastically.

For a small SIP system, start with two plastic 5-gallon buckets. For ornamental plants for indoor or patio gardening, choose decorative store-bought pots. For edibles, you can use any kind or size of planter, but 5-gallon plastic buckets have built-in handles and are relatively lightweight even when filled with soil and plants.

Some people use 2-gallon soda bottles with great success, but they generally lack UV (ultra- violet) protection and may leach harmful chemicals. Painting the bottles may solve the UV problem, and the filtering effect of the soil may neutralize harmful chemicals, but plastic buckets are simpler and easier and can water a larger planting area.

Here's how to convert two 5-gallon plastic buckets into a SIP:  

With a 3-inch hole saw, drill four 3-inch holes in the bottom of Bucket #1.

Purchase four 3-inch net cups or use four 3-inch plastic drinking cups and drill a dozen ¼-inch holes in each.

Fill the net cups or drilled plastic cups with potting soil. These cups will serve as water wicks. Put the cups in the holes you drilled in Bucket #1.

Drill at least two ¼-in overflow holes in Bucket #2, where the inserted bottom of Bucket #1 lines up.

Place Bucket #1 inside Bucket #2;

Fill Bucket #1 with potting soil. Water the soil until the water reservoir of Bucket #2 is filled and water leaks from the overflow holes.

Plant the edibles of your choosing in Bucket #1. Refill the water reservoir in Bucket #2 only as needed.

For your SIP to be successful, you must establish water wicking between the water supply and the soil. The overflow holes prevent drowning of the roots.

You can build a self-irrigating raised bed using the same principles, but it takes more steps, work, materials and care—a topic for a future article.

Workshops: 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 COMPLETELY FULL AND REGISTRATION IS CLOSED.

U. C. Master Food Preservers will teach a workshop on “Food Preserving: Canning, Drying, Freezing” on Saturday, July 15, from 10 a.m. to noon, at University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Learn the equipment required and hazards to avoid in this demonstration with recipes provided. The emphasis is on microbial food safety but biotechnology, food quality and food security will also be addressed. 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 publi 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.