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.
I remember ending last month’s to-do list with a promise that December’s garden to-do list would be shorter. What was I thinking?
There is actually a lot to do in the garden in December. If you planned ahead and were industrious in late summer, you are probably harvesting Brussels sprouts, cabbages, broccoli, kohlrabi and kales. Harvest individual Brussels sprouts from the bottom, or cut off the entire stalk and store somewhere cold while you use them. We have two upright, full stalks of bright green Brussels sprouts resting in our cool pantry, and I pop off a potful of sprouts as needed.
Beets, carrots, scallions, radishes and lettuces of all varieties are easy to grow in fall and winter. Micro-greens and Asian greens also thrive in cool and even cold weather. It is easy to fill your salad bowl from the garden at this time of year.
When the weather gets really cold and my lettuce freezes, I have found that if I do not touch the leaves until they thaw, they will often be fine. Touching them damages fragile cells, which causes the leaves to deteriorate when they thaw in the morning sun.
Carrots and radishes can be sown now, as can English peas, sugar peas, sweet peas and spinach. Perhaps you are harvesting some of these crops now if you planted them in late summer. Pomegranates seemed to ripen a little early this year, but you might have a few of those left to pick, too. Complete your olive harvest if you haven’t already. University of California Extension has instructions for curing olives in several ways.
You can plant fava beans now. They are a popular cover crop in Napa Valley, preventing erosion during the winter rains. Plowed into the soil in spring, they contribute nitrogen and biomass, replenishing fertility.
However, if you grow fava beans for the table, wait to harvest them until the beans swell inside the fuzzy green pods. After shelling them, you can eat the beans raw or cooked, peeled or unpeeled. Italians enjoy young fava beans peeled and raw, with olive oil and salt for dipping, crusty bread and a glass of red wine. You can also let the pods mature on the plant and harvest the dry beans to use for soup.
If you plant radishes right now, you may have some fast-growing varieties ready by Christmas or New Year’s. Consider crisp red ‘Cherry Belles’ or long white daikon types. Smooth- or curly-leaf spinach varieties, chard, parsley, and sets of shallots and garlic can still go in.
Because a gardener’s work is never done, you will already find transplants at the nursery for spring harvests of broccoli, cabbage, cauliflower, lettuce and arugula. Shop for rhubarb and artichokes early; nurseries offer them on a first-come, first-served basis. When the supply runs out, you won’t see them again for a year.
Nurseries may still have a few bulbs for spring bloom. Their blossoms are lovely in the garden, but consider forcing bulbs for indoor color, too. Many bulbs are sold with directions for forcing. Some instructions may recommend chilling bulbs before planting outdoors. Follow the directions and enjoy the results.
Get out your floating row covers to extend the harvest of some crops as the temperature drops. You can also use this material to keep aphids and other insect pests off broccoli and cauliflower. If you have done your winter garden cleanup and eliminated piles of debris, lumber, pots and other hiding places for snails and slugs, you won’t find many pests. If you are still finding a lot of slugs, you might need to tidy up the garden a bit more.
December brings more gray days, but it is still possible to have lots of garden color in protected spots and in pots and baskets. If blue or purple flowers cheer you, then head for the pansies and violas. Violas in yellows and oranges make a wonderful contrast in sunny baskets.
Remember to stay off your garden soil when it is wet to avoid compacting it. If you expect to plant bare-root roses, fruit trees or vines this winter, try to get the planting holes dug before heavy rains begin. Lay plastic sheeting over the planting holes to prevent them from getting too wet to work.
Begin pruning your deciduous fruit, nut and shade trees now. Do not prune evergreen shrubs, roses or vines. Pruning evergreens stimulates new growth that could be vulnerable to a cold snap. Cover your compost pile when it rains so you do not drown your hard-working microbes. Bundle up and enjoy our Napa Valley winter. January’s to-do list will surely be shorter.
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.
The first thing that struck me was here was someone who had just lost their source of income, but they had also gained something they may not have had before and that is time. Now she could prepare more time-consuming but less expensive, more nutritious food for her family. Yet she had chosen to purchase food that required minimal preparation time, was costly and for the most part lower in nutrition.
The second thing that struck me was that this woman now could have the time to devote to gardening for food to feed her family. I don’t know if she had a yard with room for a garden, had access to a community garden plot or had a friend or relative with room for a garden but if she did, then gardening for food was right for her. She could feed her family fresh veggies and also preserve some of the bounty of the garden for later consumption. Eating more nutritious food at a lower cost is a win/win situation. This is especially true as the bounty of summer gardens begins to fill our tables.
I’ve been gardening for food for many years, not because I can’t afford to buy processed foods but because I want the freshest, most nutritious organic and non-genetically engineered food possible. I want to know where my food comes from, how it was grown and I want it year round. I started with several 4 ’x 8’ raised beds and every year I added one or two more until I now have 32 raised beds. No one needs 32 raised beds for a family of two, so much of what I grow is given away and I take great pleasure in being able to do this.
Gardening for Food includes home-grown veggies such as tomatoes, summer squash and eggplant that you plant in the spring to eat in the summer plus winter-planted veggies such as garlic, onions and potatoes that can be stored and enjoyed months after harvest. The garlic we grow usually lasts for almost a year. Onions will last for months and we never have to buy potatoes between June and December.
Another spring or early summer veggie I love are shell beans as they last forever, and when you grow your own and get used to eating beans that are less than a year old you realize how much more flavorful they are at a young age. A few years ago we started growing Floriani Red Flint Corn, which is widely planted in Italy for grinding and making polenta. You’ve never had polenta as rich and flavorful as that made with your own Floriani Red Flint Corn.
Last but not least are the veggies that are planted in late summer to early fall. These include broccoli, cabbage, cauliflower, kale, kohlrabi, chard and lettuces. It’s very rewarding to watch them grow and be available to you.
Gardening for food also includes preserving some of the harvest through canning, freezing or drying so that you can enjoy the production of your garden months later. In our house, there is no such thing as too many tomatoes. Some of what isn’t eaten fresh is skinned and seeded, becoming first tomato sauce and then catsup, chili sauce, BBQ sauce, marinara sauce or reduced until it becomes tomato paste. Other tomatoes are canned whole or chopped up and canned as salsa. Chile peppers are roasted and then frozen for use later in many southwestern dishes. We dry chiles, tomatoes and herbs for use as seasonings year round.
It’s been over five years since I saw this story on the news, but I haven’t been able to get the woman out of my mind. My hope is that one person will read this article and start gardening for food and then tell another person until we have everyone eating less expensive and more nutritious food day in and day out.
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. Learn how to 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. Cost is $15 per person ($10 for Yountville residents). Class size is limited and pre-registration is required. 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 on the first Thursday of every month, from April through October, from 10:30 a.m. to noon. Master Gardeners will be on hand to answer questions. Connolly Ranch is at 3141 Browns Valley Road in Napa.
