For gardeners in July, water is the thing. If you have a drip system, visit your garden and check in with each plant. Make sure all emitters are free of dirt and debris and that water can flow freely. Adjust water timers so plants are not watered at night; many plants are susceptible to mold and fungus, and a long, damp night can encourage disease. Better to water in the early morning, when the rising sun will dry the leaves, and the roots will be hydrated for the heat of the day.
Citrus trees, stone fruit and flowering trees will appreciate a deep watering every week or two through the hottest months, but remember to cut back on water before harvest to intensify the flavor of stone fruits, and avoid peaches and nectarines that are watery and tasteless.
Check hanging baskets and potted plants under eaves. Are they getting enough water to look their best? The July sun can be pretty brutal. Occasionally soak your potted and hanging plants to completely hydrate, especially if water seems to run off quickly when you water, and the soil is dry if you prod a few inches down. Move suffering potted plants to cooler locations until temperatures ease.
Bougainvillea is an exception to the rule. Its flashy beauty does better when kept on the dry side, so do not water them until the soil is dry several inches down.
If you have dahlias in your garden, trim them back as the first flush blooms. They have worked hard. Deep water and fertilize to encourage another bloom.
If you planted zucchini, winter squash, beans or cucumbers early, you can plant them again in July. Planting another hill of zucchini or other summer squash, or cucumbers and early melons can extend your season after your original spring planting is spent. Pull out the used-up plants. Work in some new compost, water well and think about what you want to plant there next.
For fall gardeners, your choices to plant from seed are many; bush beans, beets, broccoli, cabbage, carrots, cauliflower, green onions, peas, spinach, and turnips. Winter squash and winter greens can also be planted. Kale, basil, spinach, bulb fennel, well-watered radishes, lettuce and mesclun mixes can also be sown now. Just water regularly and never allow new seedlings to dry out.
Remember when you plant seeds that the beginning is the most important. After germination, if that fragile little seedling dries out just once, it will not grow.
If you notice that your plants start to lose their vibrant green and look a little yellow around the gills, they are trying to tell you they have used up all the energy in the soil. Following the instructions on your jug of fish emulsion, or the labels on other amendments or fertilizers can help green them up and help them produce abundant crops. When your crop is harvested and the bed is empty, replenish with compost and other organic matter or plant a cover crop to furnish the nutrients your next plants will need.
Remember your garden hygiene. Keep fallen fruit and overripe vegetables picked up off the ground to avoid attracting rodents, raccoons, skunks and other pests to the garden. Rake plant material up and add to your compost pile.
After you harvest your blackberries, raspberries or ollalieberries,cut this year's spent canes all the way to the ground to refresh your plants for next year, and tie up the new canes as they begin to grow.
You can start new perennial plants from cuttings now. Choose 5-inch long shoots of fresh growth with no flowers or buds of plants including dianthus, Shasta daisies, geraniums, salvias, verbenas and many other herbaceous perennials. Choose a rooting hormone at your local nursery or garden center, and follow the directions for using it. Rooting hormone greatly improves your chances of successes with many cuttings. Use seed starting mix or succulent mix for your cuttings or make your own mixture of half perlite or vermiculite, and half peat moss. When your plants are rooted, transplant to the garden or a container with a nutritious potting soil or mix.
Whether your chores are simply picking tomatoes and watering the zucchini, or getting your greenhouse in full swing for your fall crops, take the time to look at all you have accomplished since spring. Or, if the early planting season got away from you, vow to have your first cool season garden this year. The main thing is to enjoy July. It is summertime.
UC Master Gardeners of Napa County is recruiting for the Class of 2015! Applications are available at two information meetings:
Friday July 11, 12.30-2.00
Tuesday July 22, 6-7.30
At 1710 Soscol Ave.; Suite 4; Napa, CA 94559
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.
If so, maybe these plants were trying to tell you something. Your soil may require some help providing the structure and nutrients that plants need to thrive.
You can't just put your plants in dirt and expect them to flourish. Remember: there is a difference between soil and dirt. Dirt is what you get on your clothes and hands while working in the soil. Soil is made up of elements that have been decomposing since the earth was created.
Soil is composed of bedrock and mountain stones broken down over eons by wind and rain. Since Napa Valley is in a volcanically active area, much of our soil is made up of volcanic matter deposited by the river. In addition, plants, animals and bacteria contribute to the composition of our soils. We have heard a lot about how chemicals used in the garden do not break down in the soil but remain in our streams and rivers. Natural materials are a better choice.
Consider having your soil tested to see what minerals it contains, what minerals it lacks, and how much fertilizer you need. Online merchants sell bacteria and mycorrhizae (beneficial fungi) that can help restore life to your soil. Adding manure from cows, horses or other grain-eating animals will improve the soil, but be sure the manure has been aged to kill any weed seeds. Otherwise you can expect a major weed crop wherever you spread the manure.
I live on the valley floor, where the soil includes a lot of silt deposited by the Napa River during flooding. This silt, which is clay like, creates a hard layer on top of the soil when it dries. Where the river floods its banks, this layer can be two to three inches deep or more.
Clay soils hold a lot of water but don't provide much opportunity for plants to grow. The soil particles are tiny. For comparison, if a clay particle were the size of a penny, then a particle of sand would be the size of a house. The area between soil particles is where air and water reside, and plants need both to grow. Plants in soggy soil often die of root rot.
One of the easiest ways to improve clay soil is to add compost and other organic matter. Compost is composed of organic matter that has broken-down to form humus. It has little nutrient value but it does aerate the soil and improve drainage. In contrast, worm compost (vermicompost)—the castings produced by worms that eat food scraps and other organic matter—is a nutrient-rich soil amendment. Earthworms happily munch on kitchen scraps, lawn clippings, newspaper, even cardboard.
If you would like to learn more about composting, attend one of the nine composting workshops that will be conducted this year by Napa County Master Gardeners in conjunction with partnering agencies. One workshop is entirely devoted to worm composting, and the workshop on April 12 will be conducted in Spanish. Register online at www.cityofnapa.org/compost. You can help your soil produce the healthiest plants in town. To learn more about the soil food web, I recommend the book Teaming with Microbes: The Organic Gardener's Guide to the Soil Food Web by Jeff Lowenfels and Wayne Lewis.
Workshops: Napa County Master Gardeners will conduct a workshop on “Warm-Season Veggies” on Saturday, March 15, from 9:30 am to 11:30 am, at the University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Prepare now for your most successful vegetable garden ever. Learn what to plant from seed, how to choose transplants, and when to plant for a bountiful harvest from spring into fall. Online registration (credit card only)
Mail in registration (cash or check only)
Napa County Master Gardeners will conduct a workshop on “The Small Home Vineyard” on Saturday, March 29, from 9:30 am to 11:30 am, and from 12:30 pm to 2:30 pm. at the Yountville Community Center, 6516 Washington Street, Yountville. The morning session will focus on bud break to harvest. Learn the basics of managing a small vineyard including grape physiology, canopy management, vine nutrition, fertilization, irrigation and cover crop. The afternoon session will focus on identifying and managing the most common vineyard pests, especially powdery mildew. To register,call the Parks & Recreation Department at 707-944-8712 or visit its web site.
Napa County Master Gardeners welcome the public to visit their demonstration garden at Connolly Ranch on Thursdays, from 10:00 a.m. until noon, except the last Thursday of the month. Connolly Ranch is at 3141 Browns Valley Road at Thompson Avenue in Napa. Enter on Thompson Avenue.
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.
This column addresses the role of humidity and ventilation, proper feeding and pest control. For more advice, consult the University of California’s California Garden Web site (http://cagardenweb.ucanr.edu/Houseplants/), gardening books at a local library, or the staff at nurseries with a large houseplant selection. Consider investing in a comprehensive indoor gardening guide to help you learn about the plants in your care.
Most houseplants are native to tropical areas, where conditions are warm and humid. To increase the humidity easily, place pebble trays under houseplant containers. As the moisture around the pebbles evaporates, relative humidity increases. Grouping plants also helps a bit. Surprisingly, misting the leaves does not affect humidity much, although I find that some tropical plants with large leaves seem to benefit.Other plants will rot if spritzed with water, so be sure you understand each plant’s needs.
When feeding houseplants, follow package directions to the letter. More is not better.Excess fertilizer can kill a plant.
Houseplants need nitrogen (N), phosphorus (P) and potassium (K) as well as very small amounts of other minerals, called micronutrients. Most fertilizers contain a blend of nutrients in varying proportions. Foliage plants need more nitrogen, while flowering plants need more phosphorus.
Fertilizers come in several forms, from liquid to granules to sticks. Although roots take up the most nutrients, leaves can also absorb them. However, ordinary fertilizers will scorch foliage, so be sure to select a foliar fertilizer if you intend to treat the leaves.
Common houseplant pests include aphids, fungus gnats and spider mites. There are many types of aphids, and they can increase at an alarming rate. They feed by sucking plant sap. Infestations typically appear on soft, young growing shoots and around flower buds. If you catch them early,you can vanquish aphids by pinching off affected shoots or gently washing off the aphids with tepid water. You can also spray aphids with insecticidal soap, which smothers them. After spraying, wipe them away.
Fungus gnats are tiny, dark gray flies that flit about on top of the soil. The larvae feed on rotting vegetation in the soil. Plants growing in severely infested soil appear weak, grow poorly and often lose older leaves.
To combat fungus gnats, allow the soil to dry out between each watering. Use sticky yellow traps to catch adults. Alternatively, repot the plant in fresh soil. If these measures fail and the plant is large and worth saving, you can drench the soil with Bacillus thuringiensis(Bt),a safe and effective organic pesticide.
Spider mites are probably the most dreaded houseplant pest. They pierce the leaves and suck out plant juices.They hide on the underside of leaves and may go unnoticed until the plant is seriously infected. Affected leaves may show numerous yellow pinpricks, or they may be dry and limp although still green. If uncontrolled, spider mites can kill one plant and then move on to others.
Dry conditions encourage spider mites. Keep plants humid by placing them on beds of pebbles. If only some parts of the plant are infested, clip off those parts and dispose of them in a sealed plastic bag. Treat the remainder of the plant with insecticidal soap at least twice at five-day intervals. Pesticides often do not provide controlas spider mites rapidly become resistant to them.
In an upcoming column, I’ll discuss common houseplant diseases, soil needs, repotting and propagation. In the meantime, bring your houseplant questions to the Napa County Master Gardener Help Desk (address and hours below).
Workshop: Join Napa County Master Gardeners for a workshop on “Rose Pruning” on Saturday, January 18, from 10 a.m. to noon, at the University of California Cooperative Extension (address below). January is the best time to prune your roses. Come learn pruning techniques from a certified rosarian. Bring your rose questions. Online registration (credit card only)
Mail-in registration (cash or check only).
Napa County Master Gardeners welcome the public to visit their demonstration garden at Connolly Ranch on Thursdays, from 11:00 a.m. until 1 p.m., except the last Thursday of the month. Connolly Ranch is at 3141 Browns Valley Road at Thompson Avenue in Napa. Enter on Thompson Avenue.
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.
Many gardeners have the same questions about caring for indoor plants. Why do the tips of the leaves turn brown? What’s the right amount of water? Why doesn’t my plant bloom? What’s that stuff on top of the soil, or crusted around the pot? Can I grow succulents indoors?
Indoor gardeners face many of the same issues as outdoor gardeners. They must choose their houseplants wisely and understand each plant’s requirements for light, water, temperature, humidity, soil and fertilizer. What’s more, indoor gardeners have to be actively involved in plant care.
Palms and spider plants, for example, benefit from bright light and even some direct sun. Succulents and cacti require fast-draining soil and infrequent watering, while the umbrella plant needs frequent watering to thrive indoors. Orchids placed in the sun will scorch. African violets prefer filtered light and even some fluorescent light in winter. The active indoor gardener takes time to learn about each plant’s ideal growing conditions.
The staff at local nurseries should be able to advise you about the houseplants you select. You may also want to purchase a comprehensive indoor-gardening guide to read more about the plants in your care. The University of California’s California Garden Web site (http://cagardenweb.ucanr.edu/houseplants/) can answer many questions.
Houseplants need light to manufacture their food through photosynthesis. Most foliage houseplants are evergreen and native to tropical or subtropical climates. In their natural habitat, they typically live under a canopy of taller vegetation, receiving plenty of indirect bright light but no full sun. In our homes, however, walls and roofs diminish the amount of light and create dark corners with little bright light.
In addition, the angle of light changes seasonally. Some areas of your home may experience direct light in winter, while summer’s sun is too high to enter the room. The amount of light in a room can vary dramatically. Take time to study the available light in your home and notice how it changes over time. Light duration, intensity and quality all have an impact on indoor plants.
As for water, plants need it for many chemical processes. They take it up by their roots and distribute it via a network of water-conducting tissues. Alas, water—too little or too much—contributes to many plant problems. The houseplant novice has the same question as the outdoor gardener: How often should I water my plants?
Two key rules govern houseplant watering: Never permit the soil to dry out completely, and never allow plants to stand in water for an extended time. Roots may die in either situation. As a general rule, a plant in a pot six inches or less in diameter needs water when the top inch of soil is dry. For plants in larger pots, wait to water until the top two inches are dry. Use your index finger to check for moisture. If the soil feels damp, do not water.
Ordinary tap water is usually fine for indoor plants. However, if your water is artificially softened, do not use it on houseplants.
Brown leaf tips may be an indication of inconsistent watering. Use a calendar or other reminder to track your watering schedule. Cacti and succulents do not need water as frequently as umbrella plants. Watering every houseplant every Saturday earns you points for consistency but may not be a good practice.
Providing a comfortable temperature is also essential to your houseplants’ health. Most indoor plants tolerate normal indoor temperature fluctuations. Foliage plants grow best between 70°F and 80°F during the day and between 60°F and 68°F at night. Indoor flowering plants, such as bulbs, miniature cyclamen, African violet and primrose, prefer the same daytime temperatures as foliage plants but lower nighttime temperatures, 55°F to 60°F. These lower evening temperatures promote recovery from moisture loss, intensify flower color and prolong flower life.
Avoid exposing houseplants to wide temperature fluctuations or to extremely high or low temperatures. These conditions may cause plant decline, evidenced by a spindly appearance, damaged foliage or flower drop. Be an active indoor gardener and move plants from windowsills and doorways when the temperature spikes or plummets.
In future columns, we’ll explore other houseplant requirements—for humidity and ventilation, fertilizer, soil, repotting, propagation and pest control. In the meantime, bring your houseplant questions or concerns to the Napa County Master Gardener help desk (address and hours below), or e-mail us your questions using the diagnosis form on our website.
Napa County Master Gardeners welcome the public to visit their demonstration garden at Connolly Ranch on Thursday mornings, from 10:30 a.m. until noon, except the last Thursday of the month. Connolly Ranch is at 3141 Browns Valley Road at Thompson Avenue in Napa. Enter on Thompson Avenue.
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.
August is my favorite month of the year. Who could not love tomatoes, peppers, corn and basil? Once again I planted too many tomatoes and peppers. The extras I will donate to the local food bank.
Two years the Napa County Master Gardeners were treated to a workshop by the Master Preservers from Del Norte County. This used to be a program available in most counties, but with budget cuts, it is no longer as popular. (Search for their website at Master Preservers, Del Norte, Cooperative Extension.) I have been putting up veggies for two years and now I make my own ketchup, tomato sauces, and can or freeze a number of veggies for use in the winter. This year I made zucchini pickle relish, and I think that it tastes better than the cucumber relish. And it uses up some zucchini!
For the home gardener, August and September can be the busiest and the most rewarding. The number one thing to remember is to watch the irrigation in the garden; keep it on track by checking the soil daily. These hot and windy days can speed up evaporation. Squash has a propensity to wilt in the afternoons; if it looks OK in the morning, then it does not need water.
Veggies do need to be fed on a regular schedule. Check the back of the fertilizer box for the recommended schedule. I use a blend of four parts compost, one part worm compost, and organic fertilizer with a low nitrogen number. Nitrogen is the first number on the box. Too much nitrogen will produce much vegetation, but little fruit, and a tomato is botanically classified as a fruit.
Weeding is an important chore right now; do not let weeds flower or their seeds will sprout in your winter garden.
If you had a viral soil problem this winter, July and August are the best times to solarize your soil. Put a layer of clear plastic over the infected soil and tuck into the soil. It takes about 60 days to get rid of the viruses, pests and their eggs. The soil will be ready to plant this September.
This is a good time to shear your alyssum and other ground covers. Water them and they will come back as new, or even better in September. Many perennial woody herbs can be cut back now. Save some cuttings and start with new, not so woody plants.
Other chores this month include: cutting back perennials after flowering; removing any spoiled vegetables or fruits before they attract pests and keeping the yard clean. The cleanup helps discourage pests this year and prevents overwintering of viruses and insect eggs.
Deep water your trees and shrubs to help them fend off borers and other pests during the stress of the hot weather to come.
To harvest, you will have tomatoes, cucumbers, eggplants, herbs, and peppers. Plant lettuce, parsley, and cilantro in the shade of other plants and you can enjoy them throughout the summer to fall. The shade keeps them from bolting so fast.
Fruits to watch for are: figs, stone fruits, pome fruits (apples and pears), and plums. Thinning these fruits will produce larger and more succulent fruit. Keep an eye out for the many pests that attack these fruits.
In the vegetable garden, watch for pests. Those pretty white moths produce larva that can damage your plants.
It is not too early to start seeds indoors for the fall and winter garden. As you pull up each plant in your summer garden; refresh the soil by adding compost and scratching it in about an inch. Research has shown that rototilling is not good for the health of your soil. The flora and fauna that inhabit the soil are disturbed by the deeper invasion of their habitat and have trouble returning. Besides, as one of the local Master Gardeners likes to say; “The noise of the rototiller gives the worms a headache.”
Invest in a Ball Blue Book to preserve some of your harvest. This is still the best book for all types of preserving. It covers safety, non-pressurized canning, freezing, and other methods of preserving your harvest.
Enjoy the fruits of your labor this month. You deserve it.
Vegetable Workshop: Napa County Master Gardeners will lead a workshop on “Cool Season Veggies” on Sunday, August 18, from 2 p.m. to 4 p.m. at the Yountville Community Center, 6516 Washington Street, Yountville. Grow your own vegetables even when days are short and nights are cold. The key is starting while weather and soil are still warm. Learn which vegetables will thrive in cooler temperatures, how to protect them from heat when they are getting started, and how to time plantings for months of harvest. $15 per person ($10 for Yountville residents). Register through Town of Yountville, Parks and Recreation: Mail in or Walk in registration (cash or check only). For additional information, call (707) 944-8712 or visit their web site.
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?
Open Garden Days: Napa County Master Gardeners welcome the public to their Demonstration Garden at Connolly Ranch every Thursday, except the last Thursday of the month, April through October, from 10:30 a.m. to noon. Master Gardeners will be on hand to answer questions and chat about plants. Connolly Ranch is at 3141 Browns Valley Road in Napa.
