The Loma Prietan - November/December 2010

Gardening Green

Greening Your Garden — Literally!

story and photo by Arvind Kumar

California grape (Vitis californica) is a vigorous vine that does well draped over a pergola, trellis, or fence.
California grape (Vitis californica) is a vigorous vine that does well draped over a pergola, trellis, or fence.

You want to do the right thing for the environment by planting water-wise native plants in the garden, but you also want the garden to look appealing during the long, dry California summer. No matter the season, we humans like our gardens to look green. The color green evokes lushness, fecundity, and life. How can one make California gardens stay green through the summer sustainably, without relying on an endless supply of water?

Through a careful selection of plants, it is possible to design a summer-green native plant garden. Among California's dizzying array of native plants, there are many that stay green through summer naturally. Here is a short list of suggestions, from perennial to groundcover to shrub, vine, and tree.

Think about introducing these to your garden and, once established, cutting back on the water. For contrast, combine these with blue-, gray-, silver-, and tan-colored plants to create an inviting display in the garden.

Plants With Summer-Green Foliage

An early summer blooming perennial is the coastal gumplant (Grindelia stricta platyphylla). It grows 6 in. tall and 3 ft. wide, making it a good edging plant in full sun. With yellow daisies in June through August, this plant attracts butterflies, skippers, and other insects, and it contrasts well with large plants such as deergrass (Muhlenbergia rigens).

In a partly-shady spot, try growing Douglas iris (Iris douglasiana), the local native iris. Dark green sword-shaped leaves rise to 12 in., and are adorned by exquisite purple blooms in early spring. This drought-tolerant iris is happy with monthly summer watering. Regular pulling of dry leaves promotes new growth. Cut to the ground with the onset of rains to rejuvenate the entire plant.

Coyote brush (Baccharis pilularis) is a common upright shrub in many parts of California. Near the coast, mounding forms occur naturally and will perform well in gardens as groundcovers. Several cultivars are available in the trade. 'Twin Peaks' grows 1 ft. tall, 3 ft. wide, and is slow growing. 'Pigeon Point' reaches 2 ft. tall, 6 ft. wide. Prune upright branches to keep it at the desired height. It combines well with the gray leaves and red flowers of zauschneria (Epilobium canum) in summer. Coyote brush resents summer water.

For a year-round display of shiny, dark green leaves, nothing beats Yankee Point ceanothus (Ceanothus griseus horizontalis). This low, mounding shrub loves full sun, grows 2 ft. tall and 10 ft. wide, and forms an excellent groundcover. Prune upright branches regularly to give it a low profile. Lovely blue flowers in early spring attract butterflies, bees, and other pollinators. This shrub is bullet proof.

The Channel Islands are home to a lovely subshrub that stays green all year long. The showy island snapdragon (Galvezia speciosa) grows 2-1/2 ft. tall and wide. It does better in part shade, and sports red snapdragon flowers that attract hummingbirds eight months of the year. Easily pruned and easily propagated. Protect from frost.

Larger Plants Stay Green, Too

Among large shrubs, none is as beautiful or versatile as the evergreen toyon (Heteromeles arbutifolia). In sun, it is a dense shrub that grows to 8 ft. tall and wide; in shade, it can be a 20-ft. tall, lanky tree. Frothy white flowers in May and June lead to green berries that turn bright red by December, offering a colorful feast to winter visitors such as cedar waxwings.

For summer shade, try draping California grape (Vitis californica) over a trellis or pergola. In nature, this winter-deciduous creeper occurs near streams, clambering up trees for light. In the garden, keep it in check by holding back on water and pruning a couple of times each year. Large-seeded grapes make superlative juice. Leave some on the vine to make raisins for the birds to snack on all winter long.

Few trees are as well adapted to California summers as our native oaks. For an evergreen variety, try the coast live oak (Quercus agrifolia). This is a slow-growing tree, which for many years will remain a large shrub, frequented by birds and other critters. For a deciduous and relatively fast-growing tree, try the valley oak (Quercus lobata), which is tolerant of clay and grows faster with summer water.

This is a short list of summer-green native plants I have grown in my San Jose garden. Doubtless, there are more. I encourage you to explore and experiment and share what you learn.

Sierra Club life member and California Native Plant Society board member Arvind Kumar grows native plants in his Evergreen garden. He can be reached at arvind.kumar@cnps.org.