California's ongoing water situation has produced many suggestions for dealing with drought conditions. One pertinent idea is permeable hardscapes. Permeable means that a material allows liquids or gases to pass through it.Hardscapes are the non-living or man-made sections of an outdoor area such as driveways, walkways and patios.
Traditionally a lot of the hardscapes in our yards have been made of non-permeable materials, such as concrete. Non-porous materials in a city or town environment encourage the runoff of possibly polluted waters and the overflow of the storm sewers which at times may cause flooding. Additionally because the water is unable to penetrate the surface the soil dries out and moisture is unavailable to hydrate nearby plantings,increasing the need for irrigation in the dry season.
Permeable materials allow the water to slowly percolate through. The filtering of the water by the permeable material,as well as chemical interactions with soil and soil organisms, removes a large portion of the pollutants and allows the water to return to the aquifers much refreshed. The soil is also able to store the water for the use of nearby plants so you do not have to supplement their water needs as much.
If we had cemented the area I probably would not have gone to the labor and expense of removing it. At one point we did take out a section of concrete from another area in our yard, and it was a lot of heavy work. Rather than send the concrete to the land fill, I was able to recycle it into a retaining wall. Reused concrete chunks are sometimes called “urbanite”.
I decided to check out permeable hardscapes to see what the costs were and just what materials were available out there. The selection of cement pavers, decomposed granite, gravel, mulch and so on is legion. You can also use a product called pervious concrete, which looks and acts like concrete in the landscape but allows water to pass through.
The pavers, permeable concrete, and similar products need a good base and mostly professional installation. The flagstone I liked but car traffic would probably crack the slabs. I thought of decomposed granite (DG) but the installation I found was labor intensive. I love the cobbles I have in other areas of my yard but their uneven surfaces would not work at this location.
The side yard had been filled with pea gravel for a dog run at one time. Over the years the gravel had been joined by silt and soil to create a hard packed material and it had become a haven for difficult to remove weeds. I decided just to refresh with that same material. Pea gravel is permeable. When the gravel is loose, it is easy to remove the occasional weed with a stirrup type hoe, and if you have pets the removal of pet feces is simple.
I dug the area down about 4 inches and removed the gravel/soil to another location. It made a fine walking surface around my raised beds.We then computed the amount of pea gravel needed and had it delivered. Because the location was right on the street the delivery truck was able to dump it right where it needed to be. This was super convenient as now all I had to do was spread it around with no wheel barrow involvement at all. After a few hours of hard, sweaty labor the area looked refreshed and new.
Both the cost and labor commitment fulfilled all my expectations. It looks great and more importantly it is permeable. The only downside is that the pea gravel tends to spread and needs frequent sweeping to return it to the designated area. Overall, though, I am happy with the entire project.
If you are choosing hardscapes for your yard, it is worth the time to check out permeable material options. You can beautify your landscape and conserve some of our precious water at the same time.
Garden Tour: The UC Master Gardeners of Napa County invite you to attend their sixth garden tour, “Down the Garden Path,” on Sunday, September 13. On this self-guided educational tour, you will see seven gardens by Master Gardeners in and around the City of Napa. These gardens illustrate how Napa County Master Gardeners use University of California research-based horticultural information to develop and maintain their own gardens. Tickets: $30 advance / $35 day of event. Purchase tickets here: http://ucanr.edu/ucmgnapa Or you can purchase tickets at the Master Gardener office (address below). For more information, call 707-253-4143.
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. UC Master Gardeners of Napa County ( http://ucanr.org/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.
I don't even have to walk down the street to see striking trees. From the front porch of our home, I can look a block away and see what I now know to be a deodar cedar (Cedrusdeodara) that is easily 50 feet tall standing in front of a still taller Mexican fan palm (Washingtoniarobusta).
But my fascination with the trees of Napa didn't really begin until the day I spied what looked like spiky, green bowling balls beneath a tall, pine-like tree in Fuller Park.
“What's that funny-looking tree?”
“Bunya bunya.”
By this time, I'd followed my sister-in-law and wife into the University of California Master Gardener program. To help me identify the local trees, I was directed to Trees of Napa Valley written by John Hoffman, a respected local arborist and one of the original UC Napa County Master Gardeners.
This book spurred me to pay more attention to the trees around me. I read the section on the bunya bunya (Araucaria bidwillii) and learned that it, along with most of the trees in Fuller Park, was not native to the Napa area. This prehistoric tree hails from tropical Queensland, Australia, and appears to be little changed in appearance from fossilized remains dating back to the Mesozoic Era.
The large cones that so interested me can weigh up to 15 pounds. Seeds from the cones are larger than almonds and prized as a food source by Australian aborigines. Another fine specimen of the bunya bunya can be found not far from Fuller Park on the grounds of the Bali Hai Apartments in the 1700 block of Pine Street.
The dawn redwood (Metasequoiaglyptostroides) is another “living fossil” growing in Fuller Park. This remarkable tree was planted in the park by the Browns Valley Garden Club in 1954 and is reported to be the oldest tree of its species in California. A plaque at its base identifies it as being planted in memory of Herman J. Baade, a University of California farm advisor from 1914 to 1951.
John Hoffman writes of a tree thought to be extinct whose fossilized remains were found in many areas of the world. The fossil leaves and cones look much like those of the California Coast redwood (Sequoia sempervirens). In 1941 a Japanese botanist placed the fossils into genus Metasequoia.
Coincidentally, in the same year, a Chinese forester discovered a new type of deciduous conifer in a remote area of China. It was subsequently identified as the thought-to-be-extinct dawn redwood. Its seeds were propagated and seedlings were distributed to institutions all over the world, including Kew Gardens in London. That tree, planted in 1949, still stands today.
These are just two of the many interesting trees on view in Fuller Park. Purchased by the City of Napa in 1905, this former orchard and site of bygone playing fields has become a repository of trees from around the world.
The originalTrees of Napa Valley is no longer in print. However, the UC Master Gardeners of Napa County have recently published an updated version, Trees to Know in Napa Valley, with technical editor Bill Pramuk. A certified consulting arborist and long-time local columnist, Bill has an extensive knowledge of our local trees.
This book includes fold-out maps detailing tree walks in Fuller Park and downtown Napa, a collection of John Hoffman's original essays about some of the finest trees in the area, a tree-selection guide for home landscapes, and information about Napa's Registry of Significant Trees.
Guided tree walks in Fuller Park will be offered in the future by UC Master Gardeners of Napa County. For information on upcoming tree walks and other research-based information to aid the home gardener in Napa County please visit: http://ucanr.edu/ucmnapa/
Garden Tour: The UC Master Gardeners of Napa County invite you to their sixth garden tour, “Down the Garden Path”, on Sunday, September 13. On this self-guided educational tour you will see seven gardens by Master Gardeners in and around the City of Napa. These gardens illustrate how Napa County Master Gardeners use University of California research-based horticultural information to develop and maintain their own gardens.Tickets: $30 Advance/ $35 Day of Event. Purchase tickets at http://ucanr.edu/ucmgnapa. Or you can purchase tickets at the UC Master Gardener office (address below). For more information, call 707-253-4143.
Workshop: Join UC Master Gardeners of Napa County for a workshop on “Vegetable Vexations” on Saturday, September 12, from 9:30 a.m. to 11:30 a.m., at the University of California Cooperative Extension office, 1710 Soscol Avenue, Napa. Understanding pests and blights that affect your vegetables is key to managing them. Squash that doesn't grow, tomatoes with peculiar markings, artichokes full of earwigs, plants that fail to thrive—all these and more will be discussed. Bring your own vegetable vexations to show and tell, and see how integrated pest management techniques and Master Gardeners might help.Online registration (credit card only); Mail-in registration (cash or check only).
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. UC Master Gardeners of Napa County ( http://ucanr.org/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.
For the Napa Valley, El Niño refers to a weather pattern in which warming sea surfaces cause heavier-than-average winter rains and wind with warmer-than-normal temperatures.The U.S. Climate Prediction Centerhas predicted 65 percent likelihood that we will feel the effects of El Niño as summer ends, with that probability rising to nearly 80 percent by the end of the year. The National Oceanic and Atmospheric Administration says that this weather pattern usually continues for nine to twelve months.
Because of the current drought, the idea of a wet winter is welcome to me. The coming rains are too late for a number of my trees and shrubs, which are either dead or have dead branches. And the high winds that accompany El Niño storms could blow any of these trees down. Clearly I need to trim dead branches and trees and make sure weak plants are staked properly.
El Niño storms often dump massive amounts of rain in a short time, creating flash floods and heavy water build-up in yards. You can find some good suggestions on how to handle storm water as well as how to collect it for future use at www.countyofnapa.org. In the search box, type “slow it spread it sink it” to find an online reference guide by that name.
Since good drainage is extremely important to plant health, my other pre-storm chores involve clearing a place for the rain water to go. These tasks include clearing weeds from the run-off ditches in my yard as well as cleaning out rain gutters and spouts.
Highly saturated soils make it hard for plants to survive. In wet soil, t is almost impossible for roots to take up all the oxygen that the plant needs, which causes the roots to decay. Deep roots are the first to rot. If the condition continues shallower roots will also be damaged. Even plants that don't appear to be flooded may have problems during extended wet weather. And you may not see the damage until next summer. One of the best defenses for your winter vegetable garden is to make sure you have well-drained soil and to plant in mounds.
After an El Niño season, everything may appear normal in your garden until summer temperatures top 90°F. After the 1997-98 El Niño season, Napa County farm advisor Dean Donaldson warned Master Gardeners about this phenomenon in the group's newsletter. “Sometimes tree growth is simply stunted,” wrote Donaldson. “Usually, however, people observe their beautiful trees and shrubs suddenly turning from green to yellow or reddish brown. Usually it is the entire tree and it happens within a few days of hot weather. Insects are attracted to those weakened trees and often get the blame. If the whole tree dies, you can blame El Niño.”
When those record-breaking El Niño rains subsided and weather warmed up, fungal and bacterial pathogens emerged on foliage. Many trees and shrubs evidenced phytophthora root and crown rot. Slime molds appeared on soil surfaces, and snails and slugs proliferated.
Anthracnose, fire blight, and powdery mildew all thrive after a mild, wet spring. When you see evidence of these diseases on plants, cut out and discard the affected material immediately. Sanitation is the number-one way to keep these diseases from spreading. Iron chlorosis may also be a problem in wet soils.
The best thing we can do for our gardens before an El Niño-influenced winter is to create good drainage. Afterward, watch for symptoms of root rot, fungus or bacterial diseases.
Garden Tour:The UC Master Gardeners of Napa County invite you to their sixth garden tour, “Down the Garden Path,” on Sunday, September 13. On this self-guided educational tour you will see seven gardens by Master Gardeners in and around the City of Napa. These gardens illustrate how Napa County Master Gardeners use University of California research-based horticultural information to develop and maintain their own gardens.
Tickets: $30 Advance/ $35 Day of Event. Purchase tickets at http://ucanr.edu/ucmgnapa. Or you can purchase tickets at the UC Master Gardener office (address below). For more information, call 707-253-4143.
Workshop: The UC Master Gardeners of Napa County will host a free workshop on “Worm Composting” on Saturday, September 26, from 9 a.m. to 11 a.m., at the Napa Valley Museum, 55 Presidents Circle, Yountville. Explore worm composting, an ideal solution for composting kitchen scraps and returning the nutrients to your soil, especially when outdoor space is limited. Co-sponsored by Napa Recycles! Free Online Registration.
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.org/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.
- Author: Denise Seghesio Levine
Freesias are a member of the Iridaceae family. They were first found in Cape Province, South Africa, about 200 years ago by a German physician named Friedrich Heinrich Theodor Freese. Most of the varieties that thrive in California descend from just two of the many hybrids Dr. Freese discovered.
Freesia blooms grow along one side on a slightly branched stem with tuft-like narrow leaves. Most varieties reach about one foot in height.
Many flowers have ancient myths attached to them, but freesias, being of recent discovery, leave no tales in their wake. In modern florist language, freesias symbolize innocence and friendship and are the commemorative flower for the seventh wedding anniversary.
Like other plants indigenous to Mediterranean climates, freesias do best where winters are wet and summers are dry. Many favorite plants in Napa County gardens—perhaps some you grow—originated in southern Africa.
Freesias look best planted in groups or masses rather than in tidy little rows. They bloom pretty dependably 10 to 12 weeks after planting, so with careful planning, you can have blossoms in beds and pots throughout dreary winters and rainy springs. Read the labels at the nursery, however, because some propagators pre-force corms to provide blooms as early as five to eight weeks after planting.
While gardeners in most areas wait until March to plant freesias, Napa County has warm-enough winters to give us a jump on these colorful, fragrant blooms. You will see freesia corms in local nurseries this month.
Freesia corms are fragile, and the fresher, the better. Know where you intend to plant them before you head to the nursery to pick them out. For the most robust blooms, get them in the ground or into pots as soon as you can.
To plant in beds, prepare the soil about a foot deep. Make sure the bed drains well since standing water will rot the corms. Freesias prefer full sun or light morning shade but have done well almost everywhere I have planted them. Plant the corms two to four inches apart and two inches deep, then water the bed well.
Freesias also thrive in pots. Just fill the pots with good potting soil and plant the corms about an inch deep with their pointed ends up. Keep the soil moist but not soaking wet. Six corms will fit comfortably in a five-inch pot. Be sure to plant them where you can enjoy the sight of their arching, trumpet-shaped flowers and catch their wonderful scent.
Once foliage emerges, keep the beds or pots moist. Do not let the soil dry out until the flowers have faded and the foliage begins to yellow. You can deadhead the blossoms so your garden looks neat, but leave the foliage to die back naturally. The leaves provide the energy for the corms to store for next season's blooms. If your freesias are in pots, you can move them to a resting spot, out of sight, until they are ready to bloom again.
You can experience freesias indoors in two ways. You can force bulbs in dishes or pots, or you can enjoy the blooms as cut flowers in vases.
To grow freesias indoors, plant fresh corms an inch deep, pointed end up, in regular potting soil. Water well and find a sunny, south-facing window to perch them in. Expect your bouquet in 10 to 12 weeks.
When the show is done, let the pots dry out and start over. A favorite ceramic pot full of freesias is beautiful on a desk, on a kitchen windowsill, or in a sunny bathroom.
Long-lasting freesias are a lovely choice when you are ordering a bouquet from a florist for friends or family. With a change of water daily and a little floral preservative, freesias can look fresh and smell divine for up to three weeks.
Workshop: The UC Master Gardeners of Napa County will host a free workshop on “Worm Composting” on Saturday, September 26, from 9 a.m. to 11 a.m., at the Napa Valley Museum, 55 Presidents Circle, Yountville. Explore worm composting, an ideal solution for composting kitchen scraps and returning the nutrients to your soil, especially when outdoor space is limited. Co-sponsored by Napa Recycles! Free Online Registration.
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.org/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.
- Author: Denise Seghesio Levine
If you are patient and forgo harvesting tasty green spears the first two years after planting, a properly sited asparagus bed can pay off in bountiful spring harvests of asparagus for the next 12 to 15 years. Some well-tended asparagus beds still produce after 25 years.
Asparagus is a hardy perennial that adapts to a variety of temperatures. But it is happiest in a climate like ours, where winters are cool and the ground might freeze just an inch or two.
When you are looking around for the best place to plant asparagus, keep a few things in mind. The vegetable wants plenty of sun and good drainage. And because asparagus beds last a long time, put them where they will not be bothered.
Even if home-grown asparagus won't grace your table the first two seasons, the plants provide beauty and interest in your garden. Asparagus makes a beautiful screen with soft, ferny foliage and red berries. But it is tall and can shade other plants, so plan accordingly.
If you prepare your asparagus bed correctly, you will not be digging it again for a long time. Break up the soil 18 to 24 inches deep. Add organic matter to feed the plants and provide good drainage. Aged manure, bone meal, blood meal, wood ashes, compost, worm castings and leaf mold are all good choices.
Dig in these amendments before heading off to the nursery. Asparagus crowns do best when you get them into the ground and watered soon after purchase.
You can start asparagus from seed—more economical than buying crowns—but you will need to wait an additional year before harvest. That's why most gardeners plant one-year-old crowns. At the nursery, choose plump, grayish-brown crowns that look healthy. Remove any rotten or dried roots. Plant crowns 12 inches apart; measure and mark the planting spots before you head to the nursery.
To plant, dig a trench 18 to 24 inches wide and set that amended soil aside. Return 2 to 3 inches of the amended soil to the trench spreading it along the bottom of the bed. Gently spread the roots of each asparagus crown over the mound so the crowns are slightly above the roots. Cover the crowns with 2 to 3 inches of amended soil and firm it well. As the asparagus begins to grow, add more amended soil to the trench to cover the exposed crowns until the trench is filled. Water as needed if nature doesn't.
To maintain your asparagus bed, weed thoroughly in the spring. Pull weeds gently instead of hoeing to avoid damaging the fragile new growth underground.
Do not harvest the first year after planting. The second year, harvest only lightly. Newly planted asparagus grows long storage roots. These pencil-thin, fleshy roots store the carbohydrate synthesized from sunlight that the ferny foliage captures all summer long. The following spring, this energy pushes up through the earth in exuberant growth. It is an amazing thing to see fresh asparagus spears push toward the light, sometimes growing a foot a day.
When it is time to harvest, snap off 6- to 8-inch spears at or below the soil surface. The plants can get away from me, and I am not averse to using spears that are up to 18 inches tall. But the stalks still have to snap off to make it to my kitchen; if they don't, they aren't fresh. Harvest daily in season and use immediately, or refrigerate in a plastic bag for a few days. Asparagus freezes well and can be steamed, baked, braised, grilled and used in cold and hot soups. Pickled asparagus is wonderful for appetizers or Bloody Marys.
After the harvest, let the ferny foliage grow. Female plants set attractive red berries. When the ferns start to yellow and die, or if there is an early freeze, cut the foliage back to 2-inch stubs.
Some people have a reaction to eating asparagus; it's harmless but hard to ignore. We will not talk about that, however. You know who you are.
Workshop: The U. C. Master Gardeners of Napa County will host a workshop on “Drought-Tolerant and California Native Plants” on Saturday, October, 3, from 9 a.m. to 11 a.m., at Pope Valley Fire Station, 5880 Pope Valley Road, Pope Valley. Learn about drought-tolerant and native plants and discover the elements that help them thrive in our Mediterranean climate. Learn how to use them in your own garden to replace some of your thirsty ornamentals. You will also learn about irrigation modifications to make your water use more efficient and effective.ONLINE REGISTRATION
This is a free workshop but pre-registration is requested. A minimum of 10 attendees is required or the workshop will be canceled.
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.org/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.