I knew an artist who made lithographs showing the craggy tip of an iceberg above the water line, and the massive bulk of it spreading below the surface. Many plants are like that, too: what you see only hints at the activity underground.
The extensive root systems of many shrubby natives make them drought-tolerant or great for erosion control, but they may be less vigorous or shorter-lived if restricted to containers. Since the roots can't find their own water and the pots may get hot in full sun, container plants need a little more shade and much more frequent watering. Even plants that don't tolerate water in the ground may need a little water twice a week in containers.
Why plant natives in containers, then? It's a trade-off. If your garden is mostly natives, carrying the theme into your front-porch container plantings helps unify your landscape design. With containers you can showcase special plants, grow a variety of plants in a limited space that need different growing conditions, keep your garden portable, restrict the spread of aggressive plants, or coddle some favorites. When temperatures drop, you can move tender plants in containers to shelter.
Be careful to match the plant to the proper size container and soil. Garden soil is too heavy; look for specialty soil mixes at local nurseries or supply yards. Some natives require especially fast-draining soil mix.
Small containers (under five gallons) are suited to annuals, bulbs, succulents, ferns, and some small perennials.
Bulbs grown in containers won't fall prey to gophers, and you can move the containers away after bloom. Calochortus, triteleias, wild hyacinth, or single-leaf onion can be mixed with annuals such as desert bluebells, globe gilia, farewell to spring, or baby blue eyes. Tap-rooted California poppies will bloom in pots, though they won't be as large as in the ground. I've used plants that are aggressive in small gardens, such as hummingbird fuchsia, in pots.
Pete Veilleux of East Bay Wilds has played around with container growing for several years. At his nursery in Castro Valley, he often features a few interesting plant forms and combinations in containers, and he's used many containers in his landscape designs.
Pete adds lime to ferns once a year, and he often puts a big rock in the container to shade the roots. Ferns he has grown in containers include coffee fern, bracken fern, lady fern, giant chain fern, lace fern, and western sword fern.
Meadow rue, heucheras, and wallflowers work well in small to medium containers, Pete says. He has experimented with growing native trees, such as valley oak and bristlecone pine, as bonsai specimens in small pots, and he's cultivated novel forms of other trees, such as a pillow-shaped California bay.
Grasses add bling to the garden when their flowering plumes catch the light. Pete recommends Cape Mendocino reedgrass and red fescue for containers. Most other grasses quickly outgrow containers.
In larger containers, Pete has grown bigberry manzanita, nevin barberry, vine maple, huckleberry, and various native buckwheats.
© 2007 Tanya Kucak