By Penny Pawl, U. C. Master Gardener of Napa County
I just built an African keyhole garden and I'll bet you are wondering what that is. The African keyhole garden was designed by CARE in Zimbabwe during the mid 1990s to encourage people to grow their own food. The design relied on materials that were close at hand—such as bricks, stones, branches, hay, ashes, manure and soil—to create an easy-care garden for disabled people.
The plan became so popular that many Africans began growing kitchen gardens. A so-called keyhole garden bed has a dead end opposite the opening. At the dead end is a compost bin. More than 20,000 of these have been built in Africa.
The Texas Master Gardener Association has held a number of workshops to promote this type of garden. They have also standardized the plans. Their version is a six-foot-wide garden bed with a twelve-inch-wide bin made of chicken wire in the middle. The gardener fills the bin with compostable material such as moistened newsprint, cardboard, dead plants, kitchen waste and red wiggler worms, the same components of a worm bed. The concept is that the worms will gradually decompose the material and their castings will nourish the soil and plants around the bin.
For mine, I decided to use an old garbage can with holes drilled in it. The garbage-can lid keeps out pests and any creature looking for a warm nest. I created the planting bed with building blocks set three high and cemented in place.
Alas, I had a big problem with gophers, and I needed to win that battle. So this fall, when it was time to rework the soil, I put a layer of hardware cloth on the bottom. The hardware cloth helps to keep the gophers out. It won't last forever, but it will foil the varmints for a few years. Then a mixture of clean cardboard and soil was placed over the hardware cloth. Since the bed was already in a square keyhole shape, I added the garbage can and put soil around it to hold it in place.
I fill this garbage can with the same things I put in my worm compost beds, including red wiggler worms. I have been watering it and feeding it for a few weeks to try to get it working. Eventually, the liquid and castings from the worms and other insects will work its way into the new bed areas and fertilize the soil from below rather than from on top.
Tall garden beds that have compost bins built into them are called "banana circles" by permaculture specialists. I plan to incorporate banana circles in future garden beds.
When you plant your keyhole garden, aim for variety of plants in small groups as opposed to a single crop. Some vegetables do not do well in this type of situation, such as tomatoes, potatoes, peppers, eggplant, corn and squash.
I like the concept of the keyhole garden so much—relying on a compost bin in the middle to feed the plants around it—that I plan to try it in beds without the keyhole and see what happens. These beds will need to be cleaned out and refilled every four to five years.
Keyhole gardening techniques are often used in permaculture design. For more information, consult the North Carolina State University Extension site (https://content.ces.ncsu.edu/extension-gardener-handbook/appendix-d-permaculture-design) or the Nifty Homestead site (https://www.niftyhomestead.com/blog/keyhole-garden/). You will also find more advice and books on the topic online.
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 T. Eric Nightingale, UC Master Gardener of Napa County.
"Feed me, Seymour," is a quote that often comes to my mind when I see the most famous of carnivorous plants, the Venus flytrap. This particular plant sparks the imagination because of the several small, jaw-like structures it uses to catch insects. While it may be the most recognizable of carnivorous plants, the Venus flytrap is only one of many. This mysterious form of fauna often makes me wonder just how and why carnivorous plants eat what they do.
Despite their exotic, almost alien appearance, many carnivorous plants are native to North America. They live in swampy areas where water moves constantly and slowly over sandy, nutrient-poor soil. While these plants get plenty of sunshine, their environment nonetheless would leave them malnourished if not for their clever dietary adaptions.
Carnivorous plants lure their prey using a variety of techniques such as attractive colors, smells and even ultraviolet-light emissions. Once an insect lands on the plant, the creature is usually either trapped or stuck to the leaves.
Once captured, all hope is lost. The plant excretes enzymes that slowly digest the bug, leaving behind only a crunchy mass of limbs and exoskeleton. The nutrients, particularly nitrogen, are absorbed into the plant, helping it survive its inhospitable environment.
Scientists have found that the enzymes used by the plant in this process are similar to those used by other plants to protect them from insects. They theorize that over millennia of evolution, the plants have adapted the enzymes to better serve their needs.
You may be wondering, "If these plants eat insects, how do they reproduce? Don't they need pollinators?" Yes, they do.
Carnivorous plants often employ special tactics to avoid accidently eating a friendly insect. They may vary the type of lure they use (a lure that attracts flies but not bees, for example); the timing of their bloom (such as flowering before opening for business); or simply by growing their flower structures far away from their traps. Even with these efforts, mistakes are sometimes made, and a houseguest inadvertently becomes dinner.
Perhaps because of Halloween, I found myself absorbed in morbid curiosity about these plants. Wondering about their history and how they evolved brings strange images to my mind. I like to imagine ancient carnivorous plants as big as cars, trapping and consuming large ancient animals.
While fun to think about, this scenario is unlikely. How carnivorous plant evolved remains something of a mystery as few fossils have been found. Their delicate structures do not fossilize easily. Most of our current knowledge has been gleaned from the discovery of ancient seeds and pollen.
What we do know is that carnivorous plant species evolved separately all over the world in response to similar environmental factors. This process is called coevolution. While these species may appear to be closely related, they are not.
One particularly large carnivorous plant is Nepenthes rajah, the giant montane pitcher plant. Native to Borneo, this bulbous plant lures shrews with its sweet-tasting nectar. While the shrews eat, they defecate into the pitcher, feeding the plant nutrients it needs. Nepenthes raja is usually content with this form of feeding, but will gladly dine upon any rodent that is unlucky enough to slip into the pitcher.
This information led me to wonder if carnivorous plants could be employed for pest control in our gardens. I picture a wild yet peaceful garden, guarded against intruders by an army of carnivorous plants. Flies, mosquitoes and even rats would find no comfort there, leaving me free to enjoy the fruits of my labor.
Alas, while it's easy to grow carnivorous plants (with the right preparations), they make poor exterminators. The quantity of insects they require to sustain themselves is low compared to the number of pests we wish to remove from our gardens.
Nonetheless, carnivorous plants can be a fun and enriching addition to your life. While many people think they can only be grown successfully indoors under controlled conditions, they can in fact thrive outside.
The key is to recreate their natural habitat: sunny, wet and nutrient-poor. They are so accustomed to poor growing conditions that they may die if watered with tap water. The minerals in common tap water can over-fertilize them; use only distilled water.
Workshop: U. C. Master Gardeners of Napa County will conduct a workshop on “Fruit Tree Selection and Planting” on Saturday, November 18, from 9:30 a.m. to 11:30 a.m. at the University of California Cooperative Extension office, 1710 Soscol Avenue, Napa. It's the perfect time to get the soil ready to plant bare-root fruit trees, or to plant from a pot into the ground. Learn about soil types, site selection, site preparation and first-year care. Prepare your garden now so your new fruit trees will thrive. Learn what fruit tree varieties perform well in Napa County so you can choose wisely. Online registration (credit card only); Mail-in form (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.
In early October, I chose fall garden cleanup as the topic for this article. Proper garden sanitation practices are an important part of successfully growing anything. I'm never one to do a project in advance of a deadline so I hadn't started writing when the wildfires struck Napa Valley. Now that the fires have subsided, the topic remains the same but the content is much different than I had planned.
Recovering from a wildfire presents challenges few people have experienced. It's also not a subject covered in Master Gardener training, so I needed to do some research.
For almost two weeks, local people sported face masks to avoid inhaling smoke and the ash floating in the air. Eventually the air cleared thanks to wind and a little rain. No longer were our treasured N95 face masks needed when venturing outside, or so I thought. The smoke and ash may no longer be obvious, but they are still with us. Ash is on the ground and on plants almost everywhere.
The ash deposited by forest fires is relatively nontoxic and similar to ash in a fireplace. However, any ash will contain small amounts of cancer-causing chemicals. The ash we're dealing with is not just from trees but also homes, cars and anything else that got in the way of a blaze.
I first encountered ash when I harvested some tomatoes shortly after the fires started, although I didn't realize it was ash. The tomatoes had a gritty coating that wasn't normal, so I washed them well before using. This was the right thing to do and what you should do with any vegetables, fruits or herbs grown in the fire zone. If you think the ash might be from a fire that burned plastics, metals or chemicals, err on the safe side and discard these edibles.
Ash deposits vary based on how close you were to the fires and how much the wind dropped. You need to remediate the ash so that it is no longer a personal or environmental risk. Consider the following practices for outdoor ash remediation:
Wear gloves, long-sleeved shirts and long pants to avoid skin contact. If you do get ash on your skin, wash it off as soon as possible.
Avoid stirring up the ash. Do not use leaf blowers or any other device that would propel ash into the air.
Shop vacuums and other common vacuum cleaners do not filter out small particles, but rather exhaust these particle into the air where we can breathe them. Do not use shop vacuums and other nonfiltered vacuums.
Get out your trusty N95-rated face mask and wear it whenever working around ash.
Lightly spray your plants with a hose to remove ash. Wash ash into landscaped areas wherever practical.
Ash on the ground will continue to generate airborne particles when the wind blows, so water the ground regularly.
Do not wash ash into storm drains or anywhere where the ash can contaminate the water supply.
Ash is typically acidic and won't harm your soil. Napa Valley soil tends to be alkaline so adding ash will even help balance the pH a little.
Ash represents the most widespread of the wildfire-recovery challenges. If your garden and landscape experienced intense heat, fire or fire retardant, then you have challenges that are largely beyond the scope of this article. Nevertheless, I will mention a few.
Erosion can occur when fire destroys fallen leaves, branches and plants with shallow roots. Protect bare soil with mulch, such as straw, to prevent erosion until leaves, branches and plants return.
Plants and trees stressed by fire will need irrigation. Water deeply to reach the roots.
Soil may become hydrophobic, meaning it won't absorb water. If this happens, loosen the soil to break up the surface and apply a layer of organic matter such as straw. This will help the soil absorb water.
I hope these recommendations will help everyone to recover from the recent fires.
Workshop: U. C. Master Gardeners of Napa County will conduct a workshop on “Fruit Tree Selection and Planting” on Saturday, November 18, from 9:30 a.m. to 11:30 a.m, at the University of California Cooperative Extension office, 1710 Soscol Avenue, Napa. It's the perfect time to get the soil ready to plant bare-root fruit trees, or to plant from a pot into the ground. Learn about soil types, site selection, site preparation and first-year care. Prepare your garden now so your new fruit trees will thrive. Learn what fruit tree varieties perform well in Napa County so you can choose wisely. Online registration (credit card only); Mail-in form (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.
(We're catching up. What with one thing and another, we are a bit behind posting to our blog. Thanks for sticking with us!)
Parsley, by Denise Levine, UC Master Gardener of Napa County.
Parsley. Is it the frilly, dark green garnish on your plate that goes back to the dishwasher at the end of your meal? Or is it the first herb you add to everything from omelettes to soup? Either way, parsley planting season is upon us.
Parsley (Petroselinum crispum) is a cold-tolerant biennial that easily grows through our relatively mild Napa County winters. Once established, parsley is pretty hardy, and I can attest to its willingness to come back from mild neglect. Still, for abundant bunches to cut for your kitchen through long seasons, parsley grows best in rich, evenly moist, compost-rich soil in garden beds or pots.
Parsley seed can be slow to germinate and normally takes at least 18 days. You can hasten germination by soaking parsley seeds overnight. Sow seeds ¼ inch deep and keep moist until you see germination.
If you directly sow your seeds into garden beds or boxes, sow parsley one to two inches apart in a row with quicker-germinating lettuce or radishes so you know where the seeds are. By the time you are harvesting lettuce thinnings and radishes for your fall salads, you can be thinning your now visible parsley.
Other gardeners favor planting four or five seeds in each small pot or seed block to nurture through germination. Set transplants three to four inches apart in the garden when large enough. Parsley grows up to one foot the first year and can double in size in year two.
Parsley does fine in full sun with ample water but thrives in partial shade. Keep small plants evenly moist and weed early and often to help it get established. With its deep green foliage, pretty white flowers and mostly pest-free existence, parsley can easily contribute to an edible landscaping design.
You can also purchase parsley seedlings at your favorite local nursery or garden center.
Give parsley a space where it can stay for a while. It has a two-year life cycle, but parsley self- sows easily if you let some plants flower and develop seed. At the end of the season, give the seed heads a good shake over the bed and keep moist until germination and you will soon be harvesting parsley thinnings again.
Another reason to let some parsley go to flower and then seed is to attract pollinators and birds to your garden. Parsley is in the Umbellifer family, whose decorative flowers and round seed heads are magnets for all kinds of beneficial insects. At the end of parsley's life cycle, parsley roots are prized, too. Many winter soups and stews have parsley root as their backbone, and it is often used as a substitute for turnips or parsnips. Peel them before use.
Begin to harvest outer stems of your plants when they have 8 to 10 leaves. Be sparing until the plants are established. When the parsley has filled out, harvest by grabbing a bunch and snipping it across at the stems. You will often see a new flush of tender growth. Parsley, when happy, is very generous.
I like to grow several different parsleys. Curly-leaf parsley is the darker green, frilly type that many of us think of as parsley. I like it for the deep color it contributes, minced, to grain salads or stuffed eggs. Curly parsley often finds its way into vases of flowers, too. The flat-leaf Italian varieties, both large and giant, are a kitchen staple in my house. Parsley pesto, parsley butter, parsley chopped into grain salads: there are so many ways to use parsley.
Do not wash parsley until you are ready to use it. Swish it through water to dislodge any dirt and use your salad spinner to dry, or blot with paper towels.
Fertilize parsley plants monthly with a nitrogen fertilizer, or more often if you notice leaves beginning to look less dark-green and more yellowish. Parsley is a nutritious and easy-to-grow addition to your kitchen garden. Take care of parsley, and it will take care of you.
Free Guided Tree Walk: Join UC Master Gardeners of Napa County on a fun, informational walk through beautiful Fuller Park in downtown Napa. As we meander through the park, we will talk about the park's history and introduce you to 41 different trees. Wear comfortable shoes. Water and restrooms are available and handicap accessible. Trees to Know in Napa Valley will be offered at $15, cash or check only. We are unable to process credit card payments. Meet at Fuller Park, 560 Jefferson Street, Napa. ONLINE REGISTRATION or call 707-253-4221.There is no charge for attendance and walk-ins are welcome. You can be assured of receiving a complimentary map if you sign up 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.