Marin IJ Articles
Hummingbirds in the garden
|February 16, 2004|
Hummingbirds in the garden
by Charlotte Torgovitsky
I’m always happy to have company in my garden, and probably happiest when those visitors are feathered friends. Numerous species of seed-eating birds flock to my densely planted borders and the bird feeders, and others take advantage of the rich diversity of arthropods present in my organic habitat garden.
But sometimes I wonder, who is really the visitor here? Does this garden belong to me or to the male Anna’s hummingbird scolding me for the disturbance I’m causing as I do some light pruning in his territory? These tiny birds are pugnacious and very entertaining as they aggressively confront all intruders. They choose and defend territories that are rich feeding sites, chasing off all other males that try to feed. Females are allowed to forage, and during breeding season, the male will attempt to mate with any female that enters his territory. Females are also territorial, but choose areas that provide good nesting sites.
Hummingbirds are found only in the Western Hemisphere, with the vast majority of the 320 species resident in the tropics of South and Central America. There are about 15 species that inhabit the western United States. Here in northern California only Anna’s hummingbird is a resident year round.
Hummingbirds are important pollinators, and have coevolved with many of the plants native to the Americas. Flowers are adapted to attract hummingbirds as pollinators; they are specially designed with narrow, rigid, tubular shapes leading to deep nectaries producing copious amounts of nectar. Expansive petals are unnecessary, as these little birds hover while they feed, and scent is also unimportant, as most birds have poorly developed olfactory senses.
Hummingbirds consume about one and one-half times their body weight in nectar each day. This rich source of carbohydrates meets their tremendous energy demands, but arthropods are also an essential part of the diet, providing protein, vitamins, and minerals. The hummingbirds will actually hunt insects, sallying out from a perch to catch them on the wing. Many others are eaten when they are found amongst the flowers. A diet rich in arthropods is very important when the young are being raised, and in fact, the nesting materials are often held together with spider webbing.
Each flower species that the hummingbird pollinates has anthers positioned in such a way that the pollen is deposited in a particular place on the bird’s head, neck, throat, or bill as it feeds. The stigma, too, is positioned to receive the pollen specifically from that place on the hummingbird as it forages, usually from a cluster of flowers of the same species. Thus flowers are cross-pollinated in exchange for the energy rich nectar that the hummingbird relies upon.
There are many species of Salvia indigenous to the Americas, and by growing both California natives and species from Central and South America, nectar rich flowers can be provided in succession throughout the year for Anna’s hummingbird. Salvia iodanthe, a blaze of bright magenta flowers all winter; replaces the foraging opportunities provided by Salvia leucantha, Mexican sage, and Salvia elegans, pineapple sage, both of which bloom from fall to winter. Salvia melissadora blooms in early spring, and in summer our native shrubs, Salvia clevelandii, fragrant Sage, and Salvia spathacea, hummingbird sage produce nectar for these birds in exchange for the service of pollination.
Other California native plants that provide foraging opportunities for hummingbirds are manzanitas, Arctostaphylos species, which bloom in winter; California fuschia, Zauschneria californica, blooming in summer; and our various Mimulus species, which are in bloom from spring to fall. Columbines and penstemons, both native and exotic species, also provide nectar from spring to summer.
Iochroma blooms in my Larkspur garden nearly the whole year round. Frost is rare here, since we are close to the water; so this South American native, with clusters of tubular maroon flowers, has grown to a massive fifteen-foot shrub. The flowers are favored forage, and the shrub also provides perching sites with a good vantage point of the hummingbird’s territory.
To learn more about the plants that can create a rich feeding territory in your garden join us on Saturday, February 28th at the Marin Art and Garden Center to hear Lisa Van Cleef talk about “Mexican Cloudforest Plants—Visiting the Hummingbird Locus of the World.” Lisa is a certified permaculture designer, with a fun and practical approach to sustainable and organic gardening. Her garden designs have been featured on HGTV “Landscape Smart” and KRON “Henry’s Garden” programs. Lisa also writes the Green Gardener column for the San Francisco Chronicle online edition: www.sfgate.com.
The FREE slide show and presentation begin at 1:30 p.m., Saturday, February 28, and take place in the old Barn, at the Marin Art and Garden Center in Kentfield. No reservations are required. Please park in the main lot and follow the signs to the Barn.
This article appeared in the Marin Independent Journal on February 16, 2004.