- Author: Cindy Kerson, UC Master Gardener of Napa County
As the lead of the “Low-Maintenance, Low-Water Garden” at the Las Flores Learning Garden at Napa's Las Flores Community Center, my job is to keep the plants heathy and appealing. This includes seasonal pruning and, at this time of year, weeding, weeding and weeding.
As Master Gardeners know, a weed is any plant that is not where you want it to be. That would include the volunteer tomato plant that's growing between the cracks on your front steps, already flowering. You'd have to move it to your vegetable beds to promote it from weed to plant.
The low-maintenance, low-water section of the Learning Garden was the first to be planted and is now in its fifth year. The plants we chose for this area thrive with little care. Unfortunately, the surrounding soil isn't familiar with the idea. Weeds, weeds, and more weeds appear in all their glory, especially in the spring, encouraged by the warm, moist soil.
With my Master Gardener teammates and our fancy weeding tools, we've weeded three times already this spring. Some of us bring our Hori Hori garden knives; others prefer what is commonly known as “Grandpa's weeder,” a metal pole with a lever on the bottom that will take out the root along with the weed. You can find these implements easily online. It's important to dig up the root so the weed doesn't come back. It's equally crucial to remove weeds before they flower and spread their seeds around.
It has been interesting to see the variety of weeds this year. Weed seeds are transported by many methods: by animal droppings, by the wind and by people who carry seeds on the bottoms of their shoes. Given that Master Gardeners are the only people allowed to work in the garden, I guess we are somewhat to blame.
Nurseries are also culpable. Weeds can lurk in the pots of plants you purchase, so inspect carefully before you replant. Creeping woodsorrel (Oxalis corniculate), that pretty little dark-leaved ground cover with the yellow flowers, rode into the Learning Garden with the glossy abelia. We know this because it's rampant under the abelia and it is spreading.
Oxalis is a hard one to eradicate. Its survival mechanism is to scatter its seeds whenever it's agitated. And we agitate it when we pull it up or walk on it; the wind also spreads it. Unfortunately, no organic herbicide will kill it. As Master Gardeners, we always favor integrated pest management (IPM) practices to care for landscapes. That means no inorganic chemical use, if possible.
This year, we had a vast array of weeds in the Learning Garden, so we asked our Master Gardener weed identifier extraordinaire, Patty Jordan, to help us name them. She did, and she admitted she relies on the UC IPM weed photo gallery. Young plants can look different from mature ones, and this site shows the weeds at different stages.
Our weed collection included many we've come to know over the past years, such as the common sow thistle and prickly lettuce. But we also welcomed some new ones, including prickly lettuce and bedstraw. While these are not uncommon in Napa Valley, they had not shown up in the Learning Garden before.
We also came across a couple of arbutus sprouts, which we could have taken home and potted to make more of those beautiful trees. Remember, a weed is just a plant in the wrong place.
The most intriguing weed was the oyster plant (salsify), found on the outer rim of three of our ten pink muhly grasses (Muhlenbergia capillaris). Maybe the rains woke up the seeds this year. This weed is taller than the muhly grass and has a different leaf structure, so it's clearly not a part of it. The purple flower is beautiful.
It was hard to extract the oyster plants, not because they were deeply embedded but because they were so pretty. Not knowing how invasive they might be, we decided not to take a chance. Out they came.
Weeds aside, the low-maintenance garden is just that. Seasonal moderate pruning and shaping is all that's necessary. The low water feature is also appealing, especially considering our current climate. Alas, weeds do not distinguish between high- and low-maintenance gardens.
Workshop: Join the UC Master Gardener of Napa County Rose Team for a workshop on “Summer Rose Care” on Saturday, May 4, from 10 am to noon, at University of California Cooperative Extension, 1710 Soscol Avenue, Napa (rear entrance). After the first spring blooms have faded, many rose bushes begin to show stress. Do you have black spot, rust, mildew or aphids? The Rose Team will provide research-based answers about all aspects of rose care. Attendees will be invited to join a hands-on workshop at Fuller Rose Garden in Napa on May 9 to practice what they have learned. Registration required.
Workshop: Join the UC Master Gardener of Napa County for a workshop on “Growing Olives” on Saturday, May 11, from 10 am to noon, at a private grove in Napa. Learn about olive varieties and how to plant, fertilize, irrigate, and prune these trees. Olive pests and diseases will also be discussed. Register to receive the workshop location.
Help Desk: The Master Gardener Help Desk is available to answer your garden questions on Mondays and Fridays from 10 am until 1 pm at the University of California Cooperative Extension Office, 1710 Soscol Avenue, Suite 4, Napa. Or send your questions to mastergardeners@countyofnapa.org. Include your name, address, phone number and a brief description.
- Author: David Layland, UC Master Gardener of Napa County
I find great pleasure in planting and growing perennials. In contrast to annuals, perennials are the vines, bushes, trees, and other plants that come back year after year.
Planting in spring, the season of rebirth, is particularly gratifying. Your new plants are joining the perennials that are waking up from their winter nap and sprouting new growth.
Recently I planted four fruit trees. They won't produce any fruit for a few years, but the anticipation will hold my interest as they establish themselves. I also planted raspberry and boysenberry vines and am already envisioning the fresh fruit they will yield in a few years.
Planting is a relatively easy process if you pay attention to a few factors, like site selection. If you plant a sun lover in a shady spot or situate a plant that needs good drainage in a low spot, you'll probably be replanting next year.
The area where I wanted to plant my fruit trees is the lowest spot on our property. After digging a hole, I saw ground water accumulating. This wasn't a game-ending discovery but rather a warning sign that I had better do something. My solution was to create a 15-inch berm as a planting site. The elevation would keep the roots out of harm's way.
Just because you've planted something doesn't mean you're done. Getting plants to grow is much more of a challenge. Perennial plants, bushes and trees require attention every year, such as pruning and fertilizing. You also need to watch for pests and diseases that could prevent your new plants from performing at their best.
In 2000 my wife and I planted a small Syrah vineyard that produced great fruit. However, a few years ago, the vineyard became infected with Pierce's disease, a bacterial malady spread by leafhoppers. We had to tear out the vines and either replant or find another use for the land.
With the vineyard gone, we had a large open field that was good only for growing weeds. In the warmer months, it required constant mowing. However, to quote Alexander Graham Bell, when one door closes another one opens.
Today, where Syrah vines once thrived, we now have 13 goats. This development is thanks to a chance meeting with a local family that had the goats but no home for them. I miss the Syrah made from our grapes, but going through a birthing season with the goats has given me a new appreciation for anyone raising livestock.
After grapevines, olive trees have been my biggest challenge. They aren't difficult to grow, but they do have some issues. I have 22 mature trees that, fortunately, don't require fertilization. I apply a few inches of compost, which doesn't cost much, and the trees are happy.
However, olive trees are susceptible to the olive fruit fly and require application of GF-120 NF Naturalyte Fruit Fly Bait to protect them. According to Napa County's agriculture commissioner, this product is the most popular and effective pesticide registered for olive fruit fly control.
A few years ago, we lost our entire olive crop to this little pest, so we are diligent about protecting our trees. Purchasing GF-120 is painful. For 22 trees I need at least two gallons, which costs about $700. That's a giant “ouch” in my book. You need a back sprayer for application so that's yet more expense.
In 2023 we had some good news and some bad news. The good news was that we had a record olive crop and very little fruit-fly damage. The bad news was that we didn't realize the actual size of the crop until after we had picked the olives and were starting to prune the trees. That's when we saw, hidden high up in the trees, even more olives than we had already harvested. It has been painful to harvest overripe olives that immediately went into the yard-waste can.
How did that happen? For various reasons, we couldn't prune our olive trees for two years. They had become overgrown, and by overgrown, I mean way too tall and too thick with branches. There's an old saying that a sparrow should be able to fly through an olive tree. There was no chance of that with our trees. Today, thanks to a few professional pruners, almost any size bird can fly through our olive trees.
We took our olives to a local olive mill on “community day.” They were crushed for oil along with all the other olives delivered that day. We paid 85 cents a pound to mill the olives plus the cost of plastic containers, so it cost us about $300 for 3-1/2 gallons of olive oil.
Add the fruit-fly spray to that and you have some of the most expensive olive oil in existence. If we wanted to save money, we could drive to Corning and purchase a few gallons of olive oil from a local mill, then stop for a nice dinner at Buckhorn Steakhouse in Winters.
A stroll around the garden shows our perennials are waking up and ready for another year. Plants are blooming, vines are growing, and our olive trees are ready to bloom. All in all, a good spring in the garden.
Workshop: Join UC Master Gardeners of Napa County for a “Worm or Backyard Composting Workshop” on Saturday, April 27, from noon to 2 pm, at City of Napa Senior Center, 1500 Jefferson Street, Napa. Learn about composting in your own backyard, hot composting, cool composting, or worm composting—choose your own adventure. For those taking the backyard portion, after concluding the workshop, you may purchase a discounted compost bin for $20 (one bin per household). Worm class attendees will receive a free worm compost tool kit, including the worms that you will set up with the UC Master Gardeners to take home. Register here.
Workshop: Join UC Master Gardeners of Napa County for “Irrigation for Low-Water Gardens” on Saturday, April 27, from 10 am to noon, at Las Flores Learning Garden, 4300 Linda Vista Avenue, Napa. Get instruction on how to create an efficient system for your garden. Presenters will also show how the drip system at the Las Flores Learning Garden was created. Register here.
Help Desk: The Master Gardener Help Desk is available to answer your garden questions on Mondays and Fridays from 10 am until 1 pm at the University of California Cooperative Extension Office, 1710 Soscol Avenue, Suite 4, Napa. Or send your questions to mastergardeners@countyofnapa.org. Include your name, address, phone number and a brief description.
- Author: Natasha Mantle, UC Master Gardener of Napa County
In the gardener's view of the world, vacationers can be divided into two categories: those who sit around the pool and those who scurry around taking copious pictures of unfamiliar plants.
As a Master Gardener, I belong to the second category. So, when my husband and I flew to Puerto Vallarta to get away from the atmospheric river rains, there was one thing on my mind: tropical plants.
PuertoVallarta used to be a humble fishing village. It became a vacation destination sometime in the 1960s, after Sir Richard Burton (accompanied by Elizabeth Taylor) went there to film “The Night of the Iguana.”
The town is practically wedged into the Sierra Madre tropical jungle, which spills out into the city in the most enchanting ways. Step one street away from the main drag and you are likely to encounter a mind-boggling mix of tropical, Mediterranean, and desert flora: thickets of bougainvillea, cocoa and cinnamon trees, mountain coffee, heavily scented lemons and oranges, Mexican blue palms, tamarind, banyan, fig, and rubber trees, to name a few that will make your head spin.
Seeds from these plants are lying everywhere, tempting visiting plantaholics to take them home. Don't even think about it. To protect the state's agriculture, California has strict laws about bringing in living plant material. Fortunately, I got that urge out of my system long ago, after a handful of seeds I brought back from Palm Springs grew into a sizable fan palm grove that altered our backyard in unexpected ways. As my husband dryly noted, defying an old gardening adage, “No, there isn't always room for another plant.”
Sometimes it's better to leave plants where they are and enjoy them in their natural habitat, which brings me to the highlight of our trip: Vallarta Botanical Garden.
The garden was founded in 2004. For many years, it has been a leader in nature conservancy, discovering, studying, and preserving native Mexican plants. It has a “sister garden” relationship with San Francisco and Santa Barbara Botanical Gardens. American Public Garden Association ranked it third on a list of the “Top 10 Best Botanical Gardens.” I suspect that they did not take into consideration the garden's delightful restaurant overlooking Río Horcones and serving great margaritas. Otherwise, it would have been number one.
The garden covers 79 acres, so it is impossible to see it all in one day. Most visitors spend their time in the manicured main area and do not venture into the tropical forest outside which has a vast living collection of oaks and Mexican magnolias. The Aztecs revered magnolias for their beautiful scent and shape as well as their medicinal properties.
Inside the main area are three notable attractions: orchids, a pollinator garden and a collection of succulents and cacti. The latter are part of a whimsical display featuring Mexican pottery, statues of various beasts and many ingenious plant stands.
The pollinator garden is really an alley with lush, blooming plants on both sides and the constant buzz of insects flying from one border to another. Walking through it, you almost feel like an outsider eavesdropping on nature's most intimate activity.
Although bees typically get the most credit for pollination, Mexico has a tremendous variety of beetles and flies that often perform specialized tasks due to their size, such as pollinating tiny cocoa flowers. The butterfly family (with everybody's favorite, the monarchs) is the fourth largest pollinator group.
The most important project in the garden is conservation and propagation of Mexican orchids. In contrast to Napa Valley, where virtually all the orchids for sale in stores are the same species, Mexico is home to 1,300 orchid species. Some are unique to Mexico and found nowhere else. Unfortunately, even though they grow mostly at high elevations, they are still endangered due to deforestation, poaching and climate calamities.
Replicating the orchid's natural reproduction process in a lab is a complicated affair. Consider the rare Mexican orchid, Vanilla pompona, one of the most valuable spices in the world. Its pod contains over 3,000 seeds. To successfully propagate, a single seed needs specific light, temperature, humidity, and nutrient conditions, including the presence of certain fungi that will nourish the baby orchid for its first three years.
Learning about new cultures, plants and ecosystems is always inspiring, but by the end of our trip, I was ready to head home to Napa and my own garden. Luckily, my husband was happy to oblige. We said goodbye to Puerto Vallarta but vowed to return: him to the pool, and me, back to the jungle.
To learn more about pollinating plants, visit Las Flores Learning Garden in Napa, home to more than 60 pollinator-attracting plants. In April, it will be buzzing with insects.
Tomato Plant Sale: UC Master Gardeners of Napa County holds its annual tomato plant sale on Saturday, April 13, from 9 am until sold out, at 1710 Soscol Avenue, Napa. Choose from 25 varieties grown by Napa County Master Gardeners. Plants are $5 each, cash or check only.
Workshop: Join UC Master Gardeners of Napa County for “Growing Tomatoes” on Sunday, April 14, from 2 pm to 3 pm, via Zoom. We'll discuss types of tomato plants and how to care for them, including soil and watering needs, staking, pest prevention and more. Register to receive the Zoom link.
Workshop: Join UC Master Gardeners of Napa County for “Irrigation for Low-Water Gardens” on Saturday, April 27, from 10 am to noon, at Las Flores Learning Garden, 4300 Linda Vista Avenue, Napa. Get instruction on how to create an efficient system for your garden. Presenters will also show how the drip system at the Las Flores Learning Garden was created. Register here. Help Desk:
The Master Gardener Help Desk is available to answer your garden questions on Mondays and Fridays from 10 am until 1 pm at the University of California Cooperative Extension Office, 1710 Soscol Avenue, Suite 4, Napa. Or send your questions to mastergardeners@countyofnapa.org. Include your name, address, phone number and a brief description.
- Author: Penny Pawl, UC Master Gardener of Napa County
Mark your calendars for Saturday, April 13, the UC Master Gardeners of Napa County annual tomato sale. The popular sale is as much a sign of spring as the first robin is. Seedlings will be available from 9 am until sold out, so arrive early to get the varieties you want. Bring cash or your checkbook, no credit cards, please. The address is 1710 Soscol Avenue in Napa, near the Central Valley Hardware.
All the seedlings have been grown organically by Napa County Master Gardeners. Some varieties were chosen because they were favorites from past sales. Other varieties are new to the sale this year. Review the options before you come so you can head straight for the varieties you want. You'll find the complete list here. Each tomato is photographed and described; you can almost taste them. I was introduced to ‘Kellogg's Breakfast' at last year's sale, and it became my new favorite.
The descriptions also indicate whether the variety is determinate or indeterminate. Determinate tomatoes stop growing at a certain height and then start producing fruit. Indeterminate types keep growing even after they start to bloom.
Tomatoes need support from a cage, trellis, or stake to keep the fruit off the ground. It's wise to put the support in place when you plant the tomato. I've grown some tomatoes so vigorously that I had to put a cage around a cage. Once they set fruit, tomato vines can get heavy, so be sure your supports are sturdy.
Even if you find the tomatoes of your dreams at the plant sale, don't rush home, and plant them. The soil is still too cold, and we could still get a frost. Wait to plant until the soil temperature reaches at least 60°F. I have a soil thermometer and I check the temperature at a depth of 3 to 4 inches. The soil is usually sufficiently warm by late April or early May.
By the time the soil is warm enough to plant, your tomatoes will have grown taller. Pinch off the lower leaves and plant the tomato so that only the top 3 to 4 inches is above ground. The seedling will form roots all along the buried stem. You can find detailed tomato planting instructions here, including directions on how to acclimate your seedlings to their new outdoor home.
Choose a sunny area for your tomatoes and do not plant them in the same spot you used last year. Tomatoes can carry soil-borne diseases like verticillium wilt. Rotating their location on a three-year cycle helps keep these diseases from getting established in your soil.
Once my tomatoes start to bloom, I walk around in the morning and evening and give the plants a shake. Tomato flowers have both male and female parts so they are self-pollinating but shaking them can help move the pollen from the stamen (the male part) to the stigma (the female part) of the plant. And thus, tomatoes are born. Bees will do this job for you, but I believe in using assisted reproduction to get more tomatoes to my table.
During the Master Gardener tomato sale, there will be several mini demonstrations: “Planting in Containers” at 9:30 am; “Companion Planting” at 10 am; “Tomato Problems” at 10:30 am; and “Dealing with Gophers” at 11 am. There will also be staffed booths focused on education, compost, soils, and Master Gardener recruitment.
One of the main tomato pests is the hornworm. When people first see this creature, they want to stomp on it or feed it to their chickens. I, however, encourage people to let these creatures survive. They don't eat that much.
When I see hornworms, I pick them off and put them in open garden soil with a large jug or container over them. Then I feed them a few tomato leaves every day. This is usually their last stage before digging themselves into the soil, pupating and emerging as a large sphinx moth. We don't often see these moths because they fly at night, but they are a pollinator. And we need all the pollinators we can get.
So, make your tomato shopping list and bring it with you to the sale, where you'll find about 7,000 seedlings awaiting new homes.
Tomato Plant Sale: UC Master Gardeners of Napa County holds its annual tomato plant sale on Saturday, April 13, from 9 am until sold out, at 1710 Soscol Avenue, Napa. Choose from 25 varieties grown by Napa County Master Gardeners. Plants are $5 each, cash or check only. Workshop: Join UC Master Gardeners of Napa County for “Growing Tomatoes” on Sunday, April 14, from 2 pm to 3 pm, via Zoom. We'll discuss types of tomato plants and how to care for them, including soil and watering needs, staking, pest prevention and more. Register to receive the Zoom link. Help Desk: The Master Gardener Help Desk is available to answer your garden questions on Mondays and Fridays from 10 a.m. until 1 p.m. at the University of California Cooperative Extension Office, 1710 Soscol Avenue, Suite 4, Napa. Or send your questions to mastergardeners@countyofnapa.org. Include your name, address, phone number and a brief description.
- Author: Peggy McConnell, UC Master Gardener of Napa County
Gardening provides lots of benefits to the gardener: great exercise, fresh air, and the personal satisfaction of beautifying the landscape. For me, gardening has been a lifelong hobby, but as I age, my body complains about it. I can't garden for hours as I once did. My back is angry at the end of an hour. I no longer have the strength in my hands that I need for digging or for opening bags.
As a retired occupational therapist, I have learned several tips that I use and recommend to others who want to continue gardening as they age.
First, an ounce of prevention is worth a pound of cure. Some light stretching will keep your body limber, reduce soreness, and help you garden longer. Sunscreen and a sun hat are a must. So is staying hydrated when gardening. I keep a bottle of water in my garden bag and take frequent water breaks.
Gloves prevent injury. Buy a good pair of short gloves, then wear them. Long gloves are important if you have thorny bushes, such as roses. Being pricked by thorns may lead to bacterial or fungal infections. Sunglasses not only protect your eyes from the sun but also from thorns and sharp branches. For large pruning jobs, such as fruit trees, protective glasses are a good idea.
Being organized helps conserve your energy. You can reduce the number of trips back and forth to your gardening shed if you first gather all the tools and supplies you need for the project. I keep all my hand tools in a bright green bag so if I lose the bag in my garden, I can easily find it. It holds my spade, shears, tape, and tool sharpener.
Plan your heavy work when you have the most energy, probably in the morning before it gets too hot. Take breaks between tasks. Conserving your energy allows you to garden longer. Keep chairs close to your garden beds so you can rest, hydrate, and admire your garden. An alarm on my cell phone reminds me to take breaks and/or switch tasks. A kitchen timer works as well.
Repetitive tasks, such as pruning roses, weeding or trimming for long stretches, can lead to a bad back, tendonitis, or sore muscles. Use the timer to switch tasks every so often. If you are sitting, try standing and vice versa. It gives your muscles a stretch. You will be able to garden longer and won't be as sore later.
Ask for help with tasks such as hauling heavy bags of dirt, shoveling compost, or carrying trays of plants. Use a wagon or wheelbarrow to transport heavy items if you don't have help.
Using lightweight tools instead of heavier metal ones can also help reduce back problems and conserve your energy. Use lightweight leaf bins and fill them only half full before dumping. I use a collapsible garden bag that is lightweight and folds to 3 inches to save on storage space. Lightweight plastic trugs are another option and they come in a range of sizes.
I hated wrestling with hoses, so a couple of years ago I switched to a lightweight cloth hose. It is easy to maneuver and winds without kinking. Invest in a good one as they can rip.
Ergonomic thumb-controlled sprayers are easy to use and require very little pressure. If you have a limited range of motion in your shoulders, consider investing in a long-handled hose wand to extend your reach and avoid straining to access plants.
Bending is hard on our backs. Look for a sturdy no-bend weeder (sometimes called a stand-up weeder) with good reviews.
Sitting while gardening has helped me garden longer. I bought a swivel seat online that fits on top of a five-gallon bucket. Now I can sit while pruning and place my tools inside. Another popular option is a small, foldable padded bench that can be turned over and used as a padded kneeler with handles to help you stand.
Elevated raised beds really minimize bending and they come in a variety of heights. Place outdoor chairs near them so you can rest and hydrate.
Vertical gardening with hanging baskets or growing plants on fences, walls and trellises eliminates a lot of bending. Container gardening on your patio minimizes the trek from the house if you want to snip some parsley or tarragon for dinner. I love to have fresh herbs close by when cooking.
Arthritis takes a toll on hand strength and flexibility. Choosing large-handled tools can help minimize the strength required. Lightweight aluminum tools may be a good investment. I have used pipe insulation to enlarge the handles of some tools.
If you have carpal tunnel or wrist problems—or want to avoid them—look for ergonomically designed tools that keep your wrist in a straight line. You want to minimize bending your wrist to decrease pain.
Keep your tools sharp. I keep a sharpener in my garden bag to sharpen my pruners and clippers as I go. Sharp tools conserve strength. With the right tools and tips, we can continue to enjoy gardening into our ripe old age.
Workshop: Join UC Master Gardeners of Napa County for “Home Vineyards: Important Information for a Successful 2024,” on Saturday, March 30, from 9 am to 12:30 pm.
Learn the latest about irrigation and treating viruses and mildew. Get up to date on climate change, soil health and structure, increasing soil organic matter and what happens in the vineyard post pruning. Workshop will be held in a barn at a private home vineyard near Napa. Attendance is free but you must register to get the address and additional details. https://surveys.ucanr.edu/survey.cfm?surveynumber=42128
Library Talk: Join UC Master Gardeners and Napa County Library for a talk on “Growing Tomatoes in Small Spaces” on Thursday, April 4, from 7 pm to 8 pm, via Zoom.Learn how to grow fabulous tomatoes in containers— on patios, on decks and in other small Register to receive the Zoom link.
Tomato Plant Sale: UC Master Gardeners of Napa County holds its annual tomato plant sale on Saturday, April 13, from 9 am until sold out, at 1710 Soscol Avenue, Napa. Choose from 25 varieties grown by Napa County Master Gardeners. Plants are $5 each, cash or checks only.
Workshop: Join UC Master Gardeners of Napa County for “Growing Tomatoes “ on Sunday, April 14, from 2 pm to 3 pm, via Zoom. We'll discuss types of tomato plants and how to care for them, including soil and watering needs, staking, pest prevention and more. Register to receive the Zoom link.
Help Desk: The Master Gardener Help Desk is available to answer your garden questions on Mondays and Fridays from 10 a.m. until 1 p.m. at the University of California Cooperative Extension Office, 1710 Soscol Avenue, Suite 4, Napa. Or send your questions to mastergardeners@countyofnapa.org. Include your name, address, phone number and a brief description.