Many of us think of August as a time to harvest tomatoes. I'd like to suggest that August and September are also the ideal planting time for fall, winter and spring crops.
In our mild-weather valley we can plant cool-weather vegetables as late as October. How lucky are we to be able to harvest fresh vegetables from our garden almost year round? Put in a few ‘Bibb' or ‘Butterhead' lettuce seeds now and 45 days later you will have plants that can make salads all winter long if you harvest a few outer leaves at a time.
Cool-weather vegetable gardens require much less attention than summer gardens. Because our rainy season coincides with our mild winters, soil dries out slowly. Often very little watering needs to be done.
Moist soil buffers the impact of any frost because the soil doesn't get as cold as the air. Although most vegetables will not survive prolonged severe cold, cool-season crops will survive a few days of 25ºF lows and some will even survive down to 15ºF. The University of California keeps historical frost records that suggest that Napa has only a 10 percent chance of frost at the beginning of November. But the likelihood of frost rises to 50 percent in early December. You have plenty of time to plant now and have thriving plants before winter cold sets in.
Be aware that some cold-weather crops won't grow much during the winter. Root crops such as carrots, beets, radishes and parsnips will hold at maturity in the garden until you are ready to eat them. It's almost like having an extra refrigerator. Kale, cabbage and broccoli will grow slowly but do need to have a good start before the cold sets in.
When choosing cole family crop varieties (kale, broccoli, cabbage), note if they are labeled “early” or “short season.” These varieties are less hardy than those labeled as good for overwintering. Early-harvest varieties were bred for areas with winters too severe for vegetables to survive. They need to reach maturity quickly. Hardiness has likely been bred out of those plants.
Besides being able to harvest over a longer time, you will find another advantage to planting overwintering varieties of carrots, beets, spinach and kale. When these vegetables are exposed to frost, they undergo a process sometimes called cold-sweetening. The plant stores glucose and fructose to guard against frost damage. Sugar dissolved in a plant cell makes it less susceptible to freezing in the same way that salting roads reduces ice. So a little frost often makes these crops taste sweeter.
Many gardeners prefer to plant seeds for these crops directly in the ground. However, if you start seeds inside, you can pop the seedlings into ground that you are now using for a warm-weather crop, allowing you to make optimal use of valuable garden space. Local nurseries and garden centers will also have seedlings available.
Don't forget to give your soil some extra TLC. Because you are utilizing the soil year-round, remember to dig in fertilizer and organic matter more than just once a year. Twice would be good.
When deciding where to plant cool-weather vegetables, don't overlook areas of your garden that are too shady in warm weather. The sun traverses a different path in the sky in summer and winter. So new planting areas may be available. Keep in mind that salad greens and leafy vegetables require only four hours of full sun every day.
I plan to add an extra warm glow to my holiday meals by harvesting and serving vegetables from my own garden. Now that you know how easy it is, maybe you will join me.
Do you want to become a UC Master Gardener of Napa County volunteer?
To obtain an application you must attend one of the information meetings. For meeting dates, location and times or to learn more about the program and volunteer commitment see our website.
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.
My ‘Meyer' lemon tree was a casualty. I was stumped as to why it didn't survive as I had faithfully covered it every night. I have since found out that covering your plant is not the total answer to frost protection.
To minimize frost damage, try to choose plants that are not frost sensitive. If you simply must have a plant that is frost tender, at least put it in a location that gives it a fighting chance in cold weather. Identify your garden's warmest sites, perhaps an area with western or southern exposure or a spot against a western-facing wall. The wall stores the sun's heat during the day and releases it at night.
Fertilization and pruning also play a role in frost tolerance. Discontinue fertilizers and refrain from pruning after late August. The nitrogen in fertilizers promotes growth, as does pruning, and this tender new growth is sensitive to low temperatures. Citrus trees are an exception. Consult resources like Sunset's Western Garden Book to understand your plant's fertilizer requirements going into the cold months.
I was not aware of how important it is to keep plants watered during weather extremes. A thirsty plant is already stressed. Add a frost and you have a deadly combination. If nature gives us rain in winter, your plants are hydrated and less stressed. No rain? Get out there and water your landscape.
Succulents are an exception and should be somewhat dry going into a frost. I had turned off my sprinkler system and was thoughtless as to my garden's condition. When cold weather arrived, my water-deprived and stressed garden was hit hard.
Keep the soil clear under your plantings. Mulch or debris under the plant prevents the soil from absorbing daytime heat, so it remains cold. Keeping soil cleared also helps to prevent disease and discourage pests. Cleared soil warms up faster and can release that warmth back into the air. Replace mulch in the late spring or early summer to help keep the shallow roots cool and reduce water loss in hot weather.
Frost injures plants by causing ice crystals to form in plant cells. This makes water unavailable to plant tissues and disrupts the movement of fluids. Frost-damaged leaves appear burned and shriveled and turn dark brown or black.
So how does one prepare for cold weather? Many plants can survive short periods of below-freezing temperatures. You may see some blackened branch ends and dieback but nothing life threatening.
Prolonged low temperatures cause most of the problems. If frost is forecast and it hasn't rained recently, water your landscape. Citrus and other frost-sensitive plants require further protection. Cover these plants with a lightweight, breathable fabric like floating row cover. Other commonly used materials include old sheets or bed covers. Build a structure to keep the cover from touching and burning the plant.
Tomato frames can provide support for frost cloth. Remove the cover during the day so plants can enjoy the sunshine and air. Recover at dusk. Lighting under the covers will supply heat, but make sure to use only lights and extension cords rated for outdoor use.
If you didn't heed the frost warnings, you may now have damaged plants. Resist pruning the dead or damaged foliage as it will protect the plant from further damage. Force yourself to leave the plant alone until it sends out green shoots. You have been forewarned. The frost months are fast approaching so make preparations now.
Workshop: Napa County Master Gardeners will host a workshop on “Saving and Sowing Seeds to Sustain School Gardens” on Wednesday, January 21, from 3:30 p.m. to 5:30 p.m. This workshop will introduce basics of seed-saving with children, along with simple activities for seed exploration and observation. We will demonstrate the best seed sowing methods. Participants will start late spring/early summer crops, which Master Gardeners will tend until they are ready to leave the greenhouse for school gardens. Location: Connolly Ranch Education Center Greenhouse, 3141 Browns Valley Road, Napa. This workshop is free but registration is encouraged. Click here to register: http://ucanr.edu/2015schoolgardens
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. Napa County Master Gardeners ( 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.
Whenever I encounter myths about gardening, I realize that I may be guilty of believing in some of them. As a Napa County Master Gardener, I’ve been trained to research information and to offer only science-based advice to home gardeners. So when I read something about gardening that sounds questionable, I always ask myself: fact or fiction?
Gardening myths and old wives’ tales come from many sources. Even researching this article, I found that experts have differing opinions about the validity of many firmly held beliefs.
Myth: When you can sit on the ground comfortably with a bare bottom, it’s time to sow seeds.
Truth: Taking the temperature of the soil before planting seeds or seedlings is important. For most vegetables, the soil should be between 55°F and 60°F when measured three inches deep. This warm soil helps roots to grow. But before the invention of soil thermometers, how was a gardener to know? According to folklore, farmers used their bare posteriors or their elbows to test soil warmth.
Myth: Placing gravel or pot shards in the bottom of a container improves drainage.
Truth: For many years, I planted pots this way. But during my Master Gardener training, I saw an experiment that demonstrated that soils had to be saturated before moisture would go to the next level. Putting some plain newsprint or a fine weed block in the bottom of your pot will keep soil from falling out or slugs from moving in, but gravel or shards won’t affect drainage.
Myth: For a plant to bear fruit, you must have both male and female types.
Truth: While that statement is true for some species, many plants and trees are self- pollinating. Tomatoes are a good example. The flowers contain both male and female parts and just need to be jostled a bit or buzzed by bees to move the pollen around. I usually shake the plants daily as I pass by.
Pomegranates and most varieties of Asian persimmons are also self-pollinating. For small gardens, that’s an advantage because you need only one tree to get fruit. In contrast, sweet cherries and kiwis will not produce fruit unless you have both a male and a female plant. Some apple varieties may be listed as self-fruitful, but you’ll get more fruit if you have a second variety to cross pollinate.
Most garden vegetables, including summer squash and pumpkins, produce both male and female flowers. Bees make sure the pollen gets spread around. If the spirit moves you, you can help the process along manually.
Myth: Clay pots are better for container plants than plastic pots.
Truth: It depends what’s in the pot and whether you are conscientious about watering. Clay pots do not retain moisture as well as plastic pots, and they tend to wick moisture away from the roots. Clay also is heavier than plastic and more breakable. If you tend to forget to water, then plastic may be the better choice for you.
Myth: Bleach is the best product for sterilizing garden tools.
Truth: Your garden tools need to be kept clean and sharp. Some people sterilize garden shears between each cut to avoid transmitting disease from one plant to another. Yet bleach will pit the metal on your tools, and bad guys can live in those pits. Alcohol is probably a better choice for disinfecting. However, do not clean plant wounds with alcohol as it may be toxic to them. You can also use Lysol to clean cutting tools.
Myth: After pruning a tree, treat open wounds with a wound dressing.
Truth: University research suggests that is it not necessary to put tar or other wound dressing on a pruned or injured tree. In fact, it may be counterproductive. The tree has the ability to heal itself. Using dressings can delay the healing or even cover up plant diseases. If you want to cover your tree cuts and wounds, use black paint.
Free Workshop: Napa County Master Gardeners will conduct a free workshop on “Edible Landscaping” on Wednesday, February 13, from 6 p.m. to 8 p.m. Learn how to incorporate edible plants into your landscaping, how to harvest and store fruits and vegetables for best flavor, and how to handle edibles safely. Location: University of California Cooperative Extension (address below). Online registration. Phone registration, please call (707) 253-4143
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. Napa County Master Gardeners (http://cenapa.ucdavis.edu) 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?/h4>/span>/h4>/h4>/h4>/h4>
- Author: Denise Seghesio Levine
Time for last-minute holiday shopping, and if gardeners are on your list, you are in luck. Gardeners are some of the easiest people to shop for. There is always something a gardener can use.
Gardener-friendly finds range from tiny seed packets, garden clogs and bare-root roses to big-ticket items like greenhouses. So if you are still pondering last-minute gifts, consider some of these for inside and out.
More gardeners every year are embracing old-fashioned culinary skills and learning how to preserve their harvests. Canning jars, canning supplies and cookbooks about preserving and canning are more available than ever and welcomed by new and seasoned canners alike. Responding to the renewed interest in home preserving, merchants now stock beautiful jars, BPA-free canning lids and a plethora of pickling and preserving books. Little items like decorative labels for pantry jars are fun and useful, too.
For gardeners and cooks who are ready to move beyond basic water-bath canning, consider surprising them with a pressure canner. These devices process low-acid foods that cannot be safely preserved by the water-bath method. For example, you can process plain tomatoes with salt and lemon juice in a water-bath canner, but you need a pressure canner to process tomato sauce with onions or mushrooms. Pressure canners are easy and safe to use and expand the gardener’s ability to safely stock the pantry with produce from the garden. Regardless of what kind of home preserving you or your gardening friends do, follow the directions and processing times recommended by the USDA onits website and in its publications.
Compost buckets for collecting kitchen waste are now as fanciful and decorative as cookie jars—a good choice for any home composter tired of fruit flies hovering over the scraps on their way to the compost pile. Sure, there are utilitarian metal buckets, but you can also find ceramic compost keepers in a wide palette of colors, or more whimsical buckets that look like heads of romaine lettuce. Simple compost keepers are just good-sized lidded containers, while more expensive versions have replaceable charcoal filters to help keep odor down.
Compost thermometers can help dedicated composters monitor the temperature of their compost piles. Keeping a pile hot is essential for breaking down pathogens and killing weed seeds in compost. You can find these thermometers in garden-supply and hardware stores. For an aspiring composter, consider purchasing a home compost system. There are many types to choose from.
Every gardener can use another good reference book in his or her library. Noteworthy possibilities include one updated classic and a new local publication.
Sunset has recently reissued its popular Western Garden Book. First published 80 years ago, this gardening bible has been completely revised and updated for the ninth edition. Sunset has refreshed and expanded its compendium to meet gardeners’ evolving needs. This ninth edition includes new sections on edible landscapes and fire-wise gardens, as well as information on wall and roof gardens.
Field Guide to Mushrooms of Western North America by R. Michael Davis, Robert Sommer and John A. Menge (University of California Press) will be treasured by wild-mushroom enthusiasts. Davis teaches plant pathology and mushroom identification and culture at the University of California at Davis. Sommer and Mengeare emeritus professors at Davis. The three have compiled primary descriptions and illustrations of 300 species of mushrooms, plus text-only descriptions of many more. For “shroomers,” this is a helpful new addition to the field-guide section of the bookshelf.
Of course, a wonderful gift for Napa Valley gardeners is A Month-by-Month Guide to Gardening in Napa County, written by U. C. Master Gardeners of Napa County. For tree lovers or anyone re-doing a landscape, consider Trees of Napa Valley by John Hoffman and illustrated by local Master Gardeners. Hoffman, now deceased, was a professional arborist and Napa resident. You can order both books online at http://ucanr.edu/sites/ucmgnapa/Gardening_Books/Our_Books/.
For gardeners who anxiously await the first hint of spring to start their gardening season, consider a soil thermometer. These devices take the guesswork out of when to plant. Just insert the thermometer into the soil as directed to know if your seeds are likely to sprout, or rot waiting for warmer soil. The same gardeners might also appreciate some floating row cover to extend the season or a mini-hothouse to get a jump on planting.
Ask Master Gardeners what they want for Christmas, and quite a few will tell you they would like a truckload of compost. I know that is what I am getting. I just don’t know if there will be a bow on it.
Master Gardeners are volunteers who help the University of California reach the gardening public with home gardening information. Napa County Master Gardeners (http://cenapa.ucdavis.edu) 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, 707-253-4221, 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?