By Penny Pawl, UC Master Gardener of Napa County

The tomato hornworm that so many gardeners detest has a beautiful future if we let it be. After a winter spent underground and when it is done with metamorphosis, it will become one of the loveliest and largest of the moth species.  

We never get to see this moth because it only flies after dark. It is known as the sphinx moth or hummingbird moth. Some of them fly in a manner similar to the hummingbird.  

During metamorphosis, a caterpillar transforms into a moth. The caterpillar's internal parts liquefy, reform and a moth is born. The same happens to butterflies and it is one of miracles of nature.  

I found three of these giant worms the other day munching happily on one of my tomato plants. They blend in very well with the plant, and they are as big as my finger.  

I gently pulled them off and inspected their grinding mouth parts. Then I put them under a large overturned bowl with some tomato leaves and the tomato they had been chewing on. The bow is resting on the garden soil.

Most people get upset when they see hornworms on their tomato plants. I get excited. I hate losing my precious tomatoes to them, but by putting them in a container, I give them a chance to complete their life cycle.  

Many people agree with me. We like hornworms because they assist with Integrated Pest Management, a way of gardening and farming that relies on the good bugs to manage the bad bugs without the use of pesticides.

Hornworms eat your tomatoes, but in turn, the beneficial braconid wasp lays its eggs in many of the caterpillars. These tiny wasps develop within the caterpillar skin and eventually will kill their host. They emerge from the caterpillar looking rather like rice hulls on the back of the caterpillar.  

This same process happens in other butterflies and moth larva and helps with pest management. Anise Swallowtail caterpillars, which feed on plants in the parsley and fennel family, also have parasitic wasps lay eggs in their eggs.    

When the caterpillar completes its life cycle and transforms into a cocoon, it will drill into the soil to spend the next several months. I watched one do this and it was gone so quickly I was amazed. The following summer, when the weather warms, they will hatch and begin to fly around looking for places to lay their eggs. Tomato plants are a favorite host, but they like any plant in the nightshade family, including peppers, eggplants and potatoes

I have read that marigolds, basil, borage and mint will repel tomato hornworms if planted alongside the tomatoes. Their strong odors seem to repel the moth.  

The hornworm begins life as a small egg laid on the underside of the leaf. The larva hatches and grows quickly, and as it grows it eats more and more of the host plant. After three to four weeks, it is ready to take that dive into the soil.

I raised two hornworm larvae in the house in a container a few years ago. The hornworms spent the winter in my refrigerator in a small jar with soil. When summer arrived, I moved them to the garden, but I fear the experiment was a failure. The three giants I just collected will be on their own when they decide to go into the next part of their life cycle.

UC IPM has this Pest Note on Tomato Hornworms:

http://ipm.ucanr.edu/PMG/GARDEN/VEGES/PESTS/hornworm.html

The UC Master Gardeners of Napa County are volunteers who provide University of California research-based information on home gardening. To find out more about home gardening, upcoming events or to submit gardening questions, visit the Master Gardener website (napamg.ucanr.edu). Our office is temporarily closed to walk-in questions, but we are answering questions remotely and by phone or email. Submit your gardening questions through our website, by email mastergardeners@countyofnapa.org or leave a phone message at 707-253-4143. Master Gardeners will get back to you within a few days.   

By Penny Pawl, UC Master Gardener of Napa County

I was recently at the garden of one of my fellow Napa County Master Gardeners, Cindy Watter, and was amazed by her wonderful Brugmansias (Solanaceae) and their huge blooms.

Cindy has had these plants for several years and they continue to give her and her garden guests a wonderful floral display. Some are planted in large pots and others are in the ground.

Brugmansias are sometimes called Angel Trumpets for the large dangling flowers they produce. These flowers are scented and attract pollinating moths. One species is pollinated by hummingbirds that are able to reach deep into the hanging flowers

Cindy had given me some cuttings from her plants, and I was able to root them over the winter in my hothouse in a soil mixture created for that purpose. As winter nears, Cindy cuts her Brugmansia back to one to two feet tall. She also covers them with a fabric that protects them from cold winter nights.

We live only about 10 miles apart but in vastly different microclimates. She is in the middle of Old Town Napa and big trees grow around her garden. I live beside and behind open vineyard areas and frost can be fierce, damaging tropical plants. Brugmansia are native to Central and South America and will not survive frosts.

Napa has many microclimates. Conditions at a 200-foot elevation are different than on the valley floor.

Brugmansia no longer grow in their native areas, but because of their popularity, they have been introduced to many other areas. Some people theorize that the plants no longer grow in their native areas because the animal that spreads their seed is no longer in the area.

Brugmansia bloom in a variety of colors including white, yellow, pink, orange, green, and red. Most of these plants are hybrids, bred for various flower colors and other traits. When a test plant produces a bloom in the desired color, it is reproduced by cuttings to ensure its offspring have the same traits and flower colors. Plants grown from open-pollinated seeds often revert to their native types.

I was surprised to learn that Brugmansia are in the Nightshade family, which includes potatoes, eggplants, peppers, and tomatoes. Brugmansia are poisonous and should only be admired, not tasted. However, a tropical butterfly (Placidula euryanassa) feeds on the nectar, which makes the butterflies and their larvae taste bad to predators.

While Brugmansia are related to Datura, there are differences. Plant botanists have been debating and reclassifying these plants since the mid-1700s. Datura flowers turn up and Brugmansia blooms dangle.

Brugmansia are heavy feeders. Cindy uses a balanced fertilizer about every three weeks on the potten plants to keep them healthy and growing. Because they are native to the tropics, they also like to be kept damp. If they are stressed for water, the leaves will wilt. Plants growing in the ground don't need to be watered as often.

Planted in the garden, Brugmansia can reach 15 feet in height, but most stay under that. The flowers usually appear only on new wood above a certain height. Old wood cuttings don't flower until they have forked and reach that height. The leaves are the same size as the flowers.

Brugmansia grown in pots need to be occasionally moved to a larger container or be root-pruned while dormant, and replanted. They do well in dappled shade.

Food Growing Forum: Join Napa County Master Gardeners on Sunday, July 26, from 3 p.m. to 4 p.m., for a free Zoom forum on “Watering, Irrigation and More.” This forum on food growing will continue monthly on the last Sunday of every month, with future topics announced soon. To receive the Zoom link for the July 26 forum, register at http://ucanr.edu/FoodGrowingForum2020.

The UC Master Gardeners of Napa County are volunteers who provide University of California research-based information on home gardening. To find out more about home gardening, upcoming events or to submit gardening questions, visit the Master Gardener website (napamg.ucanr.edu). Our office is temporarily closed to walk-in questions, but we are answering questions remotely and by phone or email. Submit your gardening questions through our website, by email mastergardeners@countyofnapa.org or leave a phone message at 707-253-4143. Master Gardeners will get back to you within a few days.   

By Penny Pawl, UC Master Gardener of Napa County

Napa County Master Gardeners had many compost classes planned for last spring. Then the shelter-in-place order came through. We still wanted to tell people about the importance of composting, so we decided to collaborate with the City and County of Napa to do a public workshop via Zoom.

I had no idea what an undertaking this would be. We met to discuss how to do this event, where to produce it, what the script would be and what props we would use. We had to research our presentations and gather materials to show.

Because we would be doing the presentation from a home garden, we had to figure out where the sun would be during the live workshop so we could situate the presentation table properly.  

To test our setup, one Master Gardener managed the camera outside while another was inside checking on how the workshop would look when we went live. A third person was in an off-site office monitoring the picture and sound.

We reassembled one more time to rehearse so that the webinar would go smoothly. Prior to that, we sent an event announcement with a Zoom reservation link. Luckily, we had an audience.  

I have given a hundred or more compost presentations during my years as a Master Gardener, but I have to admit I was nervous about this one in a new-to-me format.

New Master Gardener Lonnie Payne-Clark opened the session with the argument for why people should compost. The short answer is: to enrich our gardens and keep organic matter out of the landfill. I once read an article about a study in which workers had drilled several feet deep into a New York City landfill. They came up with a 25-year-old newspaper wrapped around a hot dog. The newspaper was still readable. In a landfill, material is packed so tight that no air gets in. Without air, the material can't decay.  

Regular additions of compost improve the tilth, or texture, of the soil. Worm compost is a mild fertilizer that benefits all plants.

Following Lonnie, Master Gardener Sue Helms spoke about various methods of composting: hot compost, cool compost, the do-nothing “compost happens” method and the so-called lasagna method.    

I spoke next, about using worms to compost kitchen waste. Master Gardener Cindy Watter described how to build a pile for hot composting and other methods. She also discussed the types of bins used for composting and the various tools used to manage compost piles. We took questions at the end and then congratulated each other on a job well done.  

For help making this Zoom workshop happen, we thank Kendra Bruno from the City of Napa, Amanda Griffis from the County of Napa and Napa County Master Gardener coordinator Yvonne Rasmussen.   You can watch this workshop here.  

The following week we did a worm composting workshop and distributed worm bins to 17 people who had signed up in advance. During the workshop, we built a bin and put in a banana peel and 500 worms to get things going. The worms will be fed more once they settle in and the banana peel starts to disappear.

For further soil building guidelines, click to find credible, relevant, practical (how-to) information to help you build and protect your soils, gardens, farms, ranches, environment!

https://ucanr.edu/sites/soils/

Click here to view more Master Gardener online workshops on a variety of gardening topics.

Food Growing Forum: Join Napa County Master Gardeners on Sunday, July 26, from 3 p.m. to 4 p.m., for a free Zoom forum on “Watering, Irrigation and More.” This forum on food growing will continue monthly on the last Sunday of every month, with future topics announced soon. To receive the Zoom link for the July 26 forum, register at http://ucanr.edu/FoodGrowingForum2020.

The UC Master Gardeners of Napa County are volunteers who provide University of California research-based information on home gardening. To find out more about home gardening or upcoming programs, visit the Master Gardener website (napamg.ucanr.edu). Our office is temporarily closed but we are answering questions by email or phone. Send your gardening questions to mastergardeners@countyofnapa.org or leave a phone message at 707-253-4143 and a Master Gardener will respond. Please include your phone number in your e-mail or voice message.

By Penny Pawl, UC Master Gardener of Napa County

The UC Master Gardeners of Napa County turn 25 this year. It is hard to believe that Master Gardeners have been active in the county that long.

Dean Donaldson was the county farm advisor in 1995. He decided to launch the program to help relieve some of the demands on the UC Cooperative Extension office in Napa.

The Master Gardener program originated in Washington State in 1972 when the farm advisor there decided he was not able to handle all the calls from home gardeners. The advisor-trained volunteers were tasked with answering home gardener questions using research-based information.

Since that time the program has spread to all 50 states, and Canada has adopted a similar program. In the U.S., Master Gardener programs operate under the auspices of land-grant universities, such as the University of California. Each California county manages its own program developed for the needs of its local home gardeners and climates.  

There were 20 people in the first Napa County class. Every class since then has had between 19 and 25 students. At present, Napa County has 160 active certified Master Gardeners. More than 2,000 people have participated in the program since it began.

To become Master Gardeners, people are trained over several months. They receive 50 hours or more of classroom training by knowledgeable instructors who may be university faculty, industry professionals or even Master Gardeners with specialized knowledge. The goal of the training is to impart basic information in gardening subjects and the research skills needed to answer questions from the public.  

Initially, the main need in Napa County was for volunteers to staff a help desk, answering questions from home gardeners with gardening problems. In the early days, homeowners called the help desk or visited in person. Today, most questions arrive via e-mail. We have a large library of reference books, and we consult resources online, such as University of California publications. We are an information resource for local home gardeners; we do not visit home gardens to work or consult.

Slowly the program in Napa County grew, and Master Gardeners developed new ways of reaching the gardening public. We have staffed a table at local farmers' markets and at events such as Earth Day, and we have contributed a weekly column to the Napa Register since 1999. Occasionally, we write for other publications as well.

Napa County Master Gardeners developed a demonstration garden and expanded the types of public workshops we give. We have collaborated with city and county agencies on composting workshops and water-wise workshops that many people have attended over the years. Our first workshop on composting with worms drew only three people; today, the same topic draws 15 to 20 attendees.  

Every year, the Master Gardeners' field-testing committee tests different varieties of vegetables, fruits and flowers and records its results. This database helps local gardeners know what varieties perform well in different parts of the county. We operate a speakers bureau and our members often do presentations for garden clubs and other groups. Our mobile help desk can be found at different local nurseries in spring, when home gardeners need advice on growing the plants they've just purchased.

Napa County Master Gardeners lead a monthly discussion group on gardening and nature at Napa's Senior Center. We have a Latino outreach committee and a school garden taskforce. Our tree walks are very popular and are a direct outgrowth of the book, Trees of Napa County, written by the late John Hoffman, a professional arborist and member of the first Master Gardener class. The book has been revised and is still for sale by Napa County Master Gardeners.  

In the past, we organized a biannual garden tour for the public. Today, we host an annual Fall Faire and a popular spring tomato sale. Working in groups, Master Gardener volunteers plan and execute all these activities.  

To maintain their certification, Master Gardeners must complete 12 hours of continuing education each year and volunteer 25 hours in the community. All of these activities allow Master Gardeners to develop their own gardening knowledge and experience while helping home gardeners become more successful.

Alas, our plans to celebrate our 25^th anniversary have been put on hold, along with many of our public workshops and in-person monthly meetings. Nevertheless, we continue to educate the public through our newspaper articles, blog, Facebook page, Instagram and website, and we will continue to serve the community.  

Food Growing Forum: Join Napa County Master Gardeners on Sunday, July 26, from 3 p.m. to 4 p.m., for a free Zoom forum on “Watering, Irrigation and More.” This forum on food growing will continue monthly on the last Sunday of every month, with future topics announced soon. To receive the Zoom link for the July 26 forum, register at http://ucanr.edu/FoodGrowingForum2020.

The UC Master Gardeners of Napa County are volunteers who provide University of California research-based information on home gardening. To find out more about home gardening or upcoming programs, visit the Master Gardener website (napamg.ucanr.edu). Our office is temporarily closed but we are answering questions remotely and by email. Send your gardening questions to mastergardeners@countyofnapa.org or leave a phone message at 707-253-4143 and a Master Gardener will respond shortly.