By T. Eric Nightingale, U.C. Master Gardener of Napa County
Gardening and a love for nature is on the rise these days. Many people I know would like to garden more but believe they can't because they live in an apartment or have only a small yard. That's not so. While they may not be able to have massive oaks or cultivate long rows of tomatoes, there are still many ways to grow plants.
The first task in any small space, be it a balcony or yard, is to understand the microclimate. Small yards are often protected from the elements by overhanging roofs and fences, while balconies may be more exposed to wind and rain. Study where sunlight hits your growing space. Spend a day at home watching the patterns of sun and shade as the day progresses.
Even if you have only a small yard, you can increase your growing capacity by using containers. Because they're mobile, you can “go vertical” and put them on shelving or place them in spots that would normally be impractical as a growing space. Think creatively
about where your containers can go.
Most plants, properly cared for, will do well in a container for a while at least, but they may require extra attention to keep them healthy. From personal experience, I recommend firm resolve and objectivity during the plant-selection phase. It can be easy to talk yourself into attempting to grow a cactus on a shady patio or a fern on a baking-hot balcony. In the end, both you and the plant will be unhappy with the situation.
When planting in containers, choose an appropriate potting mix. Soil pulled from your yard or garden will likely be too dense. Commercial potting mixes contain perlite and other porous ingredients that enhance aeration and drainage. If you fill a container with garden soil, the soil will settle over time and become compacted, eliminating pore space.
I have seen container gardens that incorporate old charcoal grills, rubber boots, teapots, pasta colanders and paint buckets. If it can hold soil and you can make a hole in the bottom, it can be a planter. For food production, look for food-safe containers. Certain plastics, metals and even woods may leach small amounts of chemicals. This may not be a problem with an ornamental plant, but it is undesirable for edibles. Otherwise, you are limited only by your imagination. Of course, no one will criticize you for just using terra cotta pots.
Compared to in-ground gardening, container gardening presents a few unique challenges, Plants in containers tend to need more frequent watering. Extreme weather conditions also take more of a toll. Plants in containers are more exposed and can't rely on the warmth and water reserves that soil-grown plants can access. In winter I move most of my potted plants against the house to a provide a little more shelter and warmth. Keeping them well watered and covered with frost cloth is also important during harsh winter nights.
One aspect of container planting that caught me by surprise is the issue of water quality. Over time, minerals in the water build up in the soil, sometimes to excess. This buildup is more likely when a plant is not getting thorough watering. To prevent the buildup, deep-water container plants occasionally, watching for water to flow from the bottom of the pot. This tactic will help flush out excess salts and minerals.
If you have a garden hose fed by an in-home filtration system, you may not experience mineral buildup. But if you are using softened water, you may have more problems than expected. Water softeners add salts, which quickly affect plants. One sign of excess salts and minerals in a container is a whitish crust on the soil surface.
I see this buildup in my houseplants, which are lightly watered and never exposed to rain. Poor plant health also signals soil problems. Excess salts can cause a pH imbalance, which can keep the plant from absorbing nutrients. Adding fertilizers, which contain salts, may only make the problem worse. In fact, fertilizer can also build up in containers and should be occasionally flushed as well.
Container gardening offers flexibility and the potential for creativity. It's a hobby anyone can enjoy.
Workshop: Napa County Master Gardeners will hold a workshop on “Culinary Herbs and Cocktail Garnishes” on Saturday, June 23, from 9:30 a.m. to 11:30 a.m., at Central Valley Hardware, 1100 Vintage Avenue, St. Helena. The workshop will be repeated on Sunday, June 24, from 1 p.m. to 3 p.m., at Yountville Community Center, 6516 Washington Street, Yountville. Plant a plethora of herbs to add color and delight to your plate and to your beverages. Cilantro, basils, thymes, mints and their flowers, nasturtiums, roses, pansies, borage and calendula are only the beginning. Learn to grow these useful plants. Demonstrations and hands-on activities add to the fun. Online registration (credit card only); Mail-in/Walk-in registration (check only or drop off cash payment). To register for the Yountville workshop, call the Parks & Recreation Department at 707-944-8712 or register online.
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.