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

A seed packet of Rainbow Floral Strain Mix of coleus is on my table and that is pretty exciting.  Better than a box of mixed chocolates, this non-caloric envelope of a potential rainbow of eye candy is waiting to be sown and nurtured. Living foliage kaleidoscopes will be my winter color project.

Coleus (Plectranthus scutellarioides) is actually a member of the mint and dead nettle family. As I look at the shape and texture of the leaves, I can see the resemblance.

Coleus is considered a shade plant, but many darker colors can handle some sun and some varieties are very happy in bright light. Varieties that like sun are called sun coleus and include Premium Sun Crimson Gold, Lime Delight and Chocolate Symphony.  

I recently returned from a trip to Louisiana where coleus in lime green, lemon yellow, flamingo pink and chocolate brown in wonderfully varied heights and shapes tumbled over each other in lush beds. They grew in bright, steamy sunlight throughout most of the day.

I do not know if coleus make it through the entire year in Louisiana, but in Napa Valley, coleus should be grown as an annual or dug up when temperatures get cold and brought inside to grow as a houseplant. In protected areas and some of Napa Valley's banana belts, coleus may survive winter outdoors.

You will get the most vibrant color from coleus that receive morning sun and afternoon shade, but there are coleus choices for most light conditions. While most coleus like shade, too much shade can cause plants to become weak and spindly.

Coleus are easy to propagate from cuttings, but I like the grab-bag surprise of planting from mixed seed and seeing what I get. Coleus seeds need light and warmth to germinate. Sow seeds on top of damp soil or seed starting mix, press them gently into the soil and do not cover.  

Place the pots on a heating pad, seed-starting mat or cozy window sill to get them started and keep between 70ºF and 75ºF. When your plants get two real leaves, gently transplant them into their own little pots if they are not in individual cells. As plants develop multiple leaves and branches, pinch them right above a branching junction to shape and stimulate growth. Transplant to larger containers as needed.  

When I read reviews from other gardeners who have sown these seeds, it seems that one of the hardest tasks is deciding which seedlings to thin out when all the colors and patterns are so enticing. Planting individual seeds in their own cells eliminates the need to toss fragile thinnings.

Put plants near a sunny window for the winter or plug in grow lights if natural light is scarce. Cut coleus back when they begin to bloom to keep them compact. Leaving flowers depletes the energy of the plant, and besides, the foliage is the tar, not the flowers.

If you want to grow coleus outside, grow them through the winter as houseplants or in the greenhouse, harden them off and gradually get them used to outside temperatures. Transplant when the danger of frost is past and nighttime temperature are in the high 50s and 60s.

Coleus grown outdoors enjoy the same conditions as begonias and impatiens.

Because coleus like water and frequent watering can leach nutrients, feed coleus frequently with a water-soluble fertilizer such as fish emulsion. Follow dilution directions on the bottle. Too much fertilizer will suppress vivid colors so pay attention to how your plants look as you care for them.

Use a free-draining potting or soil mix for containers and plant pots or hanging baskets where coleus will be protected from wind. Coleus branches break easily.

Which brings us back to propagating plants from cuttings. Use a clean knife, pruners or scissors or just break off branches to root for cuttings in clean water or a soilless mixture. If you have a choice, choose cuttings from the top of the plant. Hormonal action is strongest there and your chances of a successful rooting will be increased. When roots have formed, pot up the cuttings and grow indoors or harden to transplant outside.

With coleus, there are just so many choices. Coleus can be upright, trailing or rounded. Leaf texture can be lobed, scalloped, frilled, twisted, elongated or duck footed. With a huge palette of colors from deep burgundy, vivid purple, chocolate brown and neon pink to fluorescent chartreuse, coleus provide you the opportunity to design a bed, pot or garden that ranges from subtle to shocking.

If you decide to try your hand at coleus from seed, you can find Rainbow Floral Strain Mix online at Baker Creek Heirloom Seeds and Swallowtail Garden Seeds.

Workshop: U. C. Master Gardeners of Napa County will hold a workshop on “Toxic and Carnivorous Plants” on Saturday, October 27, from 9:30 a.m. to 11:30 a.m., at the University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Foxglove. Lily-of-the-valley. Wisteria. These common plants and many others are toxiix. Who knew? Sundew. Venus flytrap. Pitcher plant. Carnivorous, or so we've heard. Join the UC Master Gardeners and explore the fascinating properties that plants have to protect themselves and survive in inhospitable places.Online registration (credit card only);Mail-in/Walk-in registration (check only or drop off cash payment).

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.

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

Fall is a wonderful time to be in the garden. The cooler air is reinvigorating after the long hot days of summer. Fall is also a perfect time to plant many California natives. Many have been dormant during the summer and will soon awaken and stretch their roots within the soil. These plants will grow through the wet days of winter, preparing to bloom brightly and beautifully in spring.

The soil itself seems to approve of fall planting. Once seemingly made of stone, the clay-heavy soils in our gardens will soon become manageable once again.

It is well known that native plants are hardy, often drought-tolerant options for our gardens. When considering California natives, it can be helpful to look at a more refined list of Napa Valley natives. We live in a large and ecologically diverse state, so focusing on local flora can make your gardening more successful. Napa Valley native plants include many hardy and beautiful choices, enough to provide for almost any garden need.

As winter approaches, many gardens lose much of their color. A great plant for color from summer through fall is California fuchsia (Epilobium canum). Its silver-green foliage provides an excellent backdrop for the bright orange-red flowers. It is a low shrub, sometimes prostrate, so it is ideal for bordering a walkway. California fuchsia spreads via seed and rhizomes, so you may end up with a splash of color where you hadn't planned it.

All through the winter we will be treated to the pink and white blooms of Stanford's manzanita (Arctostaphylos stanfordiana). This manzanita can be maintained as a shrub but will reach seven feet tall if allowed. Manzanita will not only add winter color to your garden but can also shade more delicate plants during the hot summer. Manzanita also provides berries and shelter for native wildlife. Look for Stanford's manzanita the next time you are out in the woodlands of Napa Valley and the surrounding area.

If you are looking for a vining plant, look no further than Dutchman's pipe (Aristolochia californica). Its unique blooms are white with red stripes and shaped like curved bells. Dutchman's pipe is a host plant for the larva of the pipevine swallowtail, a vibrantly colored yellow and blue butterfly. Wasps also like the plant, however, and will be drawn to the fruits of the seed pods. To foil them, remove the pods before they open or cover the plant with netting until you can collect the seeds. Due to the odd shape of the flowers, Dutchman's pipewas once thought to be carnivorous. This notion has since been disproven, however.

For a low-maintenance, drought-tolerant, worry-free groundcover, try purple needlegrass (Stipa pulchra). It is an unassuming yet amazing plant. This perennial grass grows readily in many types of soil, including the clay soils of Napa Valley. The roots can grow 20 feet deep, giving it incredible drought-tolerance. Purple needlegrassworks well with other native plants, but also helps to block and suppress invasive weeds. In 2004 it was designated the official State Grass of California!

My favorite native tree is the California buckeye (Aesculus californica). It grows large and sturdy, with wide, attractive leaves that provide much-needed summer shade. The blooms this tree produces are truly incredible: many small, cream-colored flowers grouped into long, impressive cones. This show will often last through spring and summer, until the tree drops its leaves as part of its summer dormancy. Toward the end of summer, large nut-like fruits will appear. While they somewhat resemble chestnuts, these fruits are inedible.

These are just a few options of the many native plants you can add to your garden. There are many helpful resources available to those new to natives. Calflora (www.calflora.org) is a website that allows you to search for plants based on criteria such as shape, native ecosystem and lifespan. The Napa Chapter of the California Native Plant Society maintains a list of native- plant gardens and nurseries (www.napavalleycnps.org).

I heartily encourage you to investigate the possibilities of native plants. By including them in your garden you not only benefit yourself, but also the many creatures that make up our local ecosystem.

Workshop: U. C. Master Gardeners of Napa County will hold a workshop on “Toxic and Carnivorous Plants” on Saturday, October 27, from 9:30 a.m. to 11:30 a.m., at the University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Foxglove. Lily-of-the-valley. Wisteria. These common plants and many others are toxiix. Who knew? Sundew. Venus flytrap. Pitcher plant. Carnivorous, or so we've heard. Join the UC Master Gardeners and explore the fascinating properties that plants have to protect themselves and survive in inhospitable places.Online registration (credit card only);Mail-in/Walk-in registration (check only or drop off cash payment).

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.

It's almost time to plant garlic. There are a lot of decisions to be made when choosing garlic. Hardneck or softneck? Many cloves or just a few? Mild or spicy? Comparing all the features of each variety can be a daunting task, but with a little time and access to the internet, anyone can learn enough to choose the garlic types that are right for them.

There are two main types of garlic: hardneck and softneck. Each garlic variety is designated as one type or the other based on its tendency to develop flower stalks, its hardiness, and its clove formation pattern.

Hardneck varieties develop a long flowering stem called a scape. Under ground is a single row of cloves wrapped together in a papery sheath to form the bulb. Scapes should be cut from hardneck garlic plants in early summer as they can rob energy from the plant and result in smaller garlic heads. Hardneck varieties yield cloves that are easier to peel and more flavorful than softnecks, and hardnecks have fewer but larger cloves per bulb. Hardneck varieties do not store as well as softnecks. They can begin to deteriorate and shrivel within four to six months of harvest.

Softnecks are best for warmer climates as they're not generally as hardy. They store well and will last for nine to twelve months under ideal conditions. Softneck bulbs have many cloves, not just a single row like hardnecks have. Some cloves are large, some small. They do not develop a scape so their stems stay soft and flexible, making them suitable for braiding.

Be sure to purchase garlic for planting from a garlic farm, a reputable online source or your local farmers market. Grocery-store garlic is often treated with an anti-sprouting chemical to inhibit growth. It's a good idea to plant more than one variety as some may succumb to disease or won't perform as well as expected. By growing multiple varieties, you can hedge your bets and determine which varieties you want to plant in the future.

Garlic does best when planted between October 15 and February 15, but the earlier you plant, the better. The bulbs will have longer to grow and will be larger.

Plant garlic in a spot that you have not recently used for garlic or other plants from the onion family. The soil should be fertile, with good drainage. If water collects around the roots, they can rot or become diseased. A raised bed works well. Dig several inches of compost into the bed along with 10-10-10 fertilizer. Adding kelp meal will help bulb development. Plant in an area that gets at least eight hours of sun daily.

Planting garlic is relatively simple. Separate the bulb into cloves. Plant the cloves one to two inches deep, four to six inches apart and in rows one foot apart; be sure the pointed end of the clove is up. Firm the soil and water the bed. Cover with a layer of straw, chopped leaves or grass and you are done.

When the leaves begin to grow, feed the plants with a teaspoon or two of a high-nitrogen fertilizer that decomposes slowly, such as blood meal. Work the fertilizer into the soil near each plant. You can also use a foliar spray of fish emulsion, if you prefer. Repeat every four weeks until the beginning of May. In June the garlic plants stop producing new leaves and begin to form bulbs.

Once shoots emerge, water regularly until autumn rains start. If we have a dry winter, continue watering if you want large bulbs. Stop watering in May to allow the soil to dry out.

When I first started growing garlic, I followed the above guidance and planted over 20 varieties of hardnecks and softnecks. After the first harvest we hosted a tasting so that we could compare flavors. I continued to plant 20 or so varieties for a few years until I learned which varieties did best in our garden. This year I will plant Inchelium Red, Lorz Italian and Chet's Italian as all have been consistent producers.

There you have it. Now get out there and order your seed garlic so that you can start planting in October.

Workshop: UC Master Gardeners of Napa County will hold a workshop on “Toxic and Carnivorous Plants” on Saturday, October 27, from 9:30 a.m. to 11:30 a.m., at University of California Cooperative Extension, 1710 Soscol Avenue, Napa. Are you ready for a Halloween scare? Thankfully, man-eating carnivorous plants are only in the movies. Learn why most gardeners grow carnivorous plants for their beauty, not just their novelty. Many common plants are poisonous. You likely know a few but what about the others? And while you should never eat an unknown mushroom from your garden, growing edible fungi with a kit is fun, easy and tasty. Join the UC Master Gardeners of Napa County to explore the fascinating properties plants have for protection and survival. Registration (credit card); Mail-in/Walk-in registration (cash or check only) 

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.

By Corinne Yoshihara

This article is a summary of a seminar conducted by Susanne von Rosenberg, U. C. Master Gardener of Napa County. on gardening in an age of climate change.

Greenhouse gases (GHGs) are the major human-influenced cause of climate change. GHGs warm the earth's surface by trapping heat in the atmosphere. Carbon dioxide and methane are the most important of the common GHGs in influencing climate change.

In 2016, California achieved its goal of reducing its GHG emissions to below 1990 levels. California is home to almost 13 percent of the U.S. population but produces only 6.6 percent of the country's carbon dioxide emissions. The U.S. as a whole is not doing as well. Until recently, the U.S had the highest total emissions worldwide, but China has overtaken us. The United States represents 4.4 percent of global population but 15 percent of the worldwide total of emissions.

Scientists consider four primary scenarios when projecting climate change: GHG emissions peak by 2020 and decline thereafter; GHG emissions peak by 2040 and decline thereafter; GHG emissions peak by 2080 and decline thereafter; and GHG emissions continue to increase throughout the 21^st century. If we meet the goals of the second scenario, we may be able to keep global temperature rise below 2°C, the target of the Paris Climate Accord.

Today, worldwide, there is “more energy in the atmosphere, rising air and ocean temperatures, sea level rise, reduction of icepack, ocean acidification and biological change,” says von Rosenberg. In California, “Each of the three past decades has been hotter than the one before.” The year 2014 was the warmest on record, followed by 2015, 2017 and 2016. Most notably, says von Rosenberg, “Temperatures at night have increased more than during the day.”

In the Bay Area, the sea level is rising 3 millimeters per year and that rise is accelerating. This increase in the rate of change is mainly due to the increased rate of melting of Greenland and Antarctic ice. There is also a greater loss of snowpack in the Sierra Nevada and increased runoff.

There are also biological changes occurring due to climate change. Humans are experiencing more heat-related illness and mortality and more health issues related to air quality. Recent droughts and wildfires have killed trees and wildlife. Species distribution is changing. Animal and plant behaviors, such as bird migration patterns and fruit-tree maturation, are also changing.

These changes will affect us adversely. We will experience more intense storms, greater potential for floods and droughts, reduction in sea ice and effects on infrastructure and property value, not to mention loss of vegetation and wildlife.

Gardeners will have to grapple with higher overall temperatures, higher night-time temperatures, longer and more frequent extreme weather events and increased precipitation variability. Higher overall temperatures will mean higher water needs, earlier bloom times and increased insect activity. Higher night-time temperatures will result in more humid nights and potentially faster growth or fruit production. Excess heat over a long period can reduce yields. Extreme weather events mean more drought and fewer, more intense periods of rain.

What can we do? We can reduce our GHG footprint, advocate for renewable energy and educate others. In our own gardens we can conserve and manage water, be flexible, be fire-wise, be proactive with insect and disease control, pay attention to microclimates, plant the right plant in the right place and reduce our garden's carbon footprint. (Removing lawn is one place to start.) Whether we are gardeners or non-gardeners, we can all help.

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.