By T. Eric Nightingale, UC Master Gardener of Napa County

Finally, we have rain. While more determined gardeners may still be pursuing outdoor projects, I have set my sights on less-damp activities. Improving your indoor garden is a great way to spend a rainy day.

If you are like me, however, you are running low on places to put houseplants. One solution is to grow plants that need little to no soil.

Known as epiphytes, these plants have evolved other methods of obtaining the nutrients they need. Some accomplish this by absorbing much of what they need from the air, using specialized leaf structures called trichomes. Others have evolved to capture loose organic matter such as leaves dropped by taller plants. This organic matter decays in the plant's personal “compost pile” and provides the epiphyte with the nutrients it needs.

Classic epiphytes include orchids, bromeliads, anthuriums and a few types of ferns. Houseplant lovers would recognize the common, most easily cared for species of these plants. They have been a fixture of the houseplant section of garden centers for many years.

If you are new to growing epiphytes, these plants are the place to start. One example is Phalaenopsis, or the moth orchid. Species of this genus are the orchids most often seen in stores and homes. Compared to more finicky orchids they are easy to care for and bloom regularly.

You may also recognize bromeliads from the Aechmea genus. They are large-leaved, urn-shaped plants with dramatic blooms arising from the center.

Anthuriums are popular around the holidays, as their bright red, shield-shaped flowers contrast nicely against their green leaves.

Once you have mastered these popular epiphytes, investigate some less-common options. Orchids come in innumerable sizes and shapes. Some of them I find so mesmerizing that I have difficulty walking away.

Many people choose to grow epiphytes in pots filled with loose, airy bark. But there are a few other ways to make creative use of available space. Epiphytes are easily secured to boards of attractive wood, with some sphagnum moss placed around their roots. This construction can then be mounted to a wall like a piece of art. Attaching an orchid or bromeliad to a piece of driftwood or grape trunk is a great way to make a table centerpiece.

Recommended care for these plants varies, so research the exact species that you have. Generally, orchids and anthuriums prefer to be watered once a week. Use only as much water as needed to wet the medium around the roots and let it dry completely between watering.

Most bromeliads like water poured into their cup-shaped center structure. Keep the cup full but drain and refresh it about once a month.

Air plants (Tillandsia) are another low-maintenance houseplant option. Like bromeliads, to which they are related, most air plants are epiphytes, living their lives anchored to another plant. A few are known as aerophytes. These have almost no roots and will roll freely around their native desert sands.

Tillandsia are native to North and South America and cannot tolerate cold temperatures. Most also do not thrive in full sun in summer but can tolerate the cooler sun of fall and winter. Like many houseplants, they prefer bright, filtered light. Their long, thin leaves covered with fine, water-collecting fuzz give them an artistic look that makes them ideal for home decor. Their blooms are stunning pink or purple flowers that pop against the grey-green foliage.

Air plants can live almost anywhere in the home, as they do not need soil. I place mine on top of books on my bookshelves and on end tables. I have also used florist wire to secure them to the sides of shelving and railings, as well as to the trunks of some of my larger houseplants.

If your living space is generally cool and humid, your air plants will need watering less often than in a hot, dry home. Some people keep their air plants in globes or terrariums. These are stylish and also increase the amount of humidity around the plant, reducing the need for frequent care.

Most homes are fairly dry due to air conditioning. Air plants in an air-conditioned environment should be watered two to three times a week. Simply collect your Tillandsia and drop them into a bowl of water. Leave them in the water no more than 15 to 20 minutes. Shake excess water from between the leaves. Water in the crevices can promote rot if it does not evaporate quickly. For that reason, I usually leave my air plants upside-down in a dry location for at least an hour. If your plants do not dry out completely within four hours, they will eventually rot.

Tillandsia rarely need fertilizer. If you suspect your plants do need a feeding, you can find appropriate fertilizer at most garden centers. It is sold in small containers, as it should be applied conservatively, no more than once a month.

The UC Master Gardeners of Napa County are volunteers who provide UC research-based information on home gardening and answer your questions. To find out more about upcoming programs or to ask a garden question, visit the Master Gardener website (http://napamg.ucanr.edu) or call (707) 253-4221 between 9 a.m. and noon on Mondays, Wednesdays or Fridays.

By Denise Seghesio Levine, U. C. Master Gardener of Napa County    

Many years ago, I spent a memorable Mother's Day weekend at a lovely bed and breakfast just outside of Mendocino. Sited on the west side of the highway, we could hear the waves crashing and knew our lodging was near the water, but it was too dark to see much when we arrived.

When the sun rose the next morning, we poured our hot coffee into big white mugs and walked out our door into the small private garden. We were intending to trek across the grass to see the sea when a glorious and amazing display of foxglove greeted us.

We saw a forest of nodding, bell-shaped blossoms climbing up waving stalks, rising from the large, flappy leaves surrounding the base of these whimsical plants. The tallest were adorned with abundant blossoms of deep purple with spotted throats. Others were colored soft apricot. More towers of bell blossoms were pure white while others were soft variations and blends of pinks, whites, lavenders and deep purples. 

Remembering this magical place and thumbing through one of my garden manuals, I was reminded that it is time to plant foxglove in the garden for flowers next spring.

Foxglove (Digitalis) is a biennial. Traditionally, a gardener would sow foxglove seed in the spring, or existing plants would self sow. Over the first year, the plants would develop their root systems and strong stems with basal leaves, rewarding the gardener with blooms the second summer.

To start foxgloves, scatter the tiny seeds on the surface of potting soil and keep moist until they germinate. Transplant carefully into individual pots and tend until spring when you can place them in your garden.

Now is a good time to wander the perennial aisle of your favorite nursery to get a head start with foxglove seedlings. Many varieties and colors are available in six-packs to plant for your own nodding forest next summer. Sizes range from over six feet tall to a small garden-friendly three-foot size.

You can also wait until spring, when you will find new hybrids that bloom the first year or seedlings that will bloom next summer.  But plants that go into the ground now will have all winter to develop root systems. Your planning will result in stronger, healthier, showier plants next year.

Read the label directions for spacing when you bring your plants home. Usually a spacing of 12 to 18 inches between plants provides enough room for foxglove to reach optimum size. Foxglove prefers acidic soil, and three to four hours of sun a day is typically enough to produce a showy display. Foxglove can be grown in dappled, shaded forest areas or bring interest and color to darker areas of the cottage garden or wild garden. They are deer proof, a bonus for many Napa Valley gardeners.

Native to the Mediterranean, other parts of Europe, Asia and the Canary Islands, foxglove are remarkably pest resistant. All parts of the plant are poisonous if ingested, which may have something to do with their resistance to creatures that munch.                                         

Wild foxglove is rarely bothered by pests. It is a very tough plant. But newer varieties can be susceptible to powdery mildew, mealy bugs, slugs and aphids. To avoid mildew, space plants far enough apart to provide air flow. Crowded plants are more likely to suffer. Remove dead leaves and debris from around plants to avoid slugs. If you find aphids, simply wash them off with a spray of clean water.

Foxglove readily self-sow if open pollinated and naturally grow in clumps or patches. That habit gives us a clue about how to plant them in our gardens. Taller specimens benefit from staking, although if they are healthy and protected from wind, staking may not be needed. Shorter varieties rarely need it.  

After most of the blooms are spent on the initial stalk, cut the stalk down. It will likely produce colorful side shoots.

Foxglove appreciate a generous application of mulch. (Think forest floor.) Add compost or feed shortly after planting and give them a booster of nutrients after the first bloom to reward them for a show well done.

When our first killing frosts arrive, remove any blackened leaves to eliminate hiding places for insects and slugs over the winter. If hundreds of seedlings start to appear after the first rains, thin or transplant extras. Crowded foxglove plants will be disappointing. 

And for the curious, digitalis comes from the Latin word for fingers. A blossom slips easily over a finger, like a little glove. Of course, if you are a fox, your whole paw should fit.

 The UC Master Gardeners of Napa County are volunteers who provide UC research-based information on home gardening and answer your questions. To find out more about upcoming programs or to ask a garden question, visit the Master Gardener website (http://napamg.ucanr.edu) or call (707) 253-4221 between 9 a.m. and 12 noon on Mondays, Wednesdays or Fridays.

By Susanne von Rosenberg, UC Master Gardener of Napa County

If you've ever bought gardening items from a catalog or website, odds are that you are starting to receive seed catalogs for 2020. Seed catalogs are awe-inspiring, kind of like a fitness magazine is for the average person.

Because seed catalogs are so enticing, it's important to read them with a bit of a critical eye. Feel free to dream and enjoy. Then, when you're ready to go from fantasizing about all the amazing things that you could grow (if only you had more time, or garden space, or maybe a different climate) to what would actually be right for you and your garden, here are some things to consider.

First, where does the seed catalog originate (and where are its trial gardens)? I've received seed catalogs from New England, New Mexico, the Pacific Northwest, the upper Midwest, Missouri, Central California and more. When seed companies describe how their varieties perform, not only are they giving you information that reflects optimal growing conditions for that variety, they are also reflecting the results that they see in their trial gardens. Which seed company is most likely to have seeds that will do well in my Napa garden, and whose description of the plants' performance will come closest to what I can expect?

Second, does the catalog give you all the information you need to make a good decision? Many catalogs skimp on important information. They are doing a terrific job painting a picture for your imagination, but you need more than a lovely vision to make a good decision for your garden.

At minimum, for plants you are already familiar with, you need to know the days to maturity (or flowering period), the mature size of the plant, its disease resistance, and whether that particular variety was developed for a specific climate.

Many of us regularly grow tomatoes and understand the conditions they prefer. But when we decide to grow a new variety, it's important to know whether it takes 60 or 90 days to mature from transplant; whether it is a determinate variety that will stop growing at four feet or less, or an indeterminate type that will keep growing; and, of course the size of the full-grown tomato. It's also helpful to know if this new variety is resistant to soil-borne diseases like verticillium wilt and fusarium wilt.

But it's equally important to know if that particular tomato was developed for a specific climate, such as foggy San Francisco or hot and humid Florida. The less you know about a specific variety or type of plant, the more information you need to make the right decision.

A good seed catalog will tell you the plant family or provide the scientific name. The catalog description should also indicate whether the seed is hybrid, open-pollinated or organic; the minimum number of seeds in the packet; the typical planting dates for various parts of the country; frost tolerance; sun or shade requirements; how thirsty that plant is; and whether it has any special needs.

Some seed companies certify that all of their seeds are GMO-free. If the seed catalog doesn't provide enough information, you'll need to do some research to fill in the blanks.

Note what the seed catalog fails to mention. If the description goes on and on about the appearance but is silent about the productivity or taste, you may have a plant that has superb or unusual color but produces only a few of the desired flowers or vegetables. Or it could be tasteless or finicky about growing conditions.

What a catalog description doesn't say can be revealing about a variety's weaknesses. Taste is subjective, and my idea of a tasty tomato may be different from yours, so look for a detailed description. It can be quite entertaining to figure out what is not being said.

Finally, be aware that the plant described in the catalog was probably grown under optimal conditions. For vegetables, that means that your days-to-harvest will almost always be longer, and you may not get the same yield. For ornamental plants, it may mean later flowering or less-showy blooms than you see in the catalog. Be skeptical about that ubiquitous term “up to,” as in “up to six feet tall” or “up to two feet long.” Again, that's under optimal growing conditions. While it's possible you'll grow a 2-pound tomato or a 16-foot-tall sunflower, it's likely that most of your tomatoes will be smaller and that your sunflowers will be too.

So, enjoy your seed catalogs and your dreams of lush plants-to-be. Then bring on your inner investigator when it comes time to actually choose seeds.

The UC Master Gardeners of Napa County are volunteers who provide UC research-based information on home gardening and answer your questions. To find out more about upcoming programs or to ask a garden question, visit the Master Gardener website (http://napamg.ucanr.edu) or call (707) 253-4221 between 9 a.m. and noon on Mondays, Wednesdays or Fridays.

By Susanne von Rosenberg, UC Master Gardener of Napa County

When I first moved to Napa 14 years ago, autumn rains arrived fairly reliably around the middle of October. As we are all painfully aware now, autumn rains have been starting later and later…and sometimes not at all.

There is no rain in the near-term forecast, and the National Oceanographic and Atmospheric Administration (NOAA) Climate Predictions Center foresees a 33 percent chance of below-normal rainfall through November coupled with a 60 percent chance of above-normal temperatures. The longer-term prediction for our area is for slightly below-normal rainfall.

The change in rainfall pattern we've been experiencing, with rains coming later than they used to, is consistent with what climate-change models predict. While we can expect roughly the same amount of rain, we will wait longer for it and it will come in fewer, more intense events.

So we need to get used to longer dry seasons. On the other hand, we need to be prepared for heavy rains. How should we adjust our gardening practices to address this change?

Let's talk about an extended dry season first. It's definitely a good idea to continue all the water- conservation practices that we instituted during the last drought. Choose drought-tolerant plants, including natives that are adapted to summer-dry climates. Install proper irrigation systems, such as drip irrigation, to water only those plants that truly need it and in the amount they truly need.

Adjust your watering according to the season. With cooler, shorter autumn days, plants require less water, even if it isn't raining. Mulch your plants to keep the soil cool and reduce evaporation.

We also need to reconsider our fall watering habits. It used to be possible to stop watering trees by late August and many other plants by mid-September. With the change in climate, you now need to continue to water until the rains finally arrive. Also consider our fall heat and low-humidity periods. Look for signs that your plants need water. Drooping leaves and/or dull leaves are two primary indicators. Get to know how your plants show they are thirsty.

How much and how often should you water with this new climate? For annual plants, simply test the soil with your finger. If the soil feels moist one to two inches down, you do not need to water yet. Keep checking and you'll soon have a sense how much water your plants need in this cooler season and how quickly they dry out when we get Diablo winds.

For trees, you can either dig down six inches to see if the soil is dry (this is the best way to check), or simply extend the time between watering. If you were watering your trees once a month in the summer, you might wait five to six weeks for the next round, and then six to seven weeks (mid- to late November) for the next round. Still no rain by New Year's? It might be time to water again! Even our native and other drought-tolerant plants may need supplemental water when rains are delayed.

More frequent heavy rains are another outcome of climate change. We will need to be able manage more rainfall on our properties. Heavy rain can damage soil structure, wash away topsoil and produce standing water in low or poor-drainage areas. You can protect your soil structure by mulching. (Yet another benefit of mulching.) Observe how water flows on your property during a heavy rain. Your goal is to slow down the flow, which you can do by spreading it out, and also by including areas where you intentionally allow the water to pool and infiltrate. Overall, the better your soil, the more rainfall it can absorb and the more water it can hold. Organic mulches do wonders to improve your soil – so, yes, keep mulching.

After a heavy rain, you may see water pooling in areas where you don't want it. In that case, you need to improve the drainage in that area. The best approach is to divert water from that area and to create additional opportunities for water to drain away. You can raise the soil level, dig small swales or create shallow berms. Small changes can make a big difference. You may also find, as I have, that as you improve the soil, your standing-water problem will diminish and eventually disappear.

Gardeners are a resilient and persistent bunch. With preparation, we can manage some of these climate-change challenges.

The UC Master Gardeners of Napa County are volunteers who provide UC research-based information on home gardening and answer your questions. To find out more about upcoming programs or to ask a garden question, visit the Master Gardener website (http://napamg.ucanr.edu) or call (707) 253-4221 between 9 a.m. and noon on Mondays, Wednesdays or Fridays.