Home & Garden

Why are hummingbirds flocking to UC Davis?

A hummingbird feeds on nectar from a Mexican white sage at the UC Davis hummingbird garden.
A hummingbird feeds on nectar from a Mexican white sage at the UC Davis hummingbird garden. rbyer@sacbee.com

Plant it and they will come.

That’s particularly true of hummingbirds. Grow their favorite flowers and they’ll flock to those blooms, buzzing excitedly between bushes. Tubular flowers – full of nectar and preferably red – always get their attention.

More proof can be found in the UC Davis Arboretum’s new public demonstration garden, dedicated to hummingbirds. It’s as if the university planted a bird-happy all-you-can-sip buffet.

“We planted this area in spring,” said Ellen Zagory, the arboretum’s horticulture director, as she recently toured the garden. “The birds took a little while to find everything – the flowers had to start blooming – but now, they just love it. Once the trees and shrubs mature, it will be packed.”

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An Anna’s Hummingbird samples the Mexican white sage in the new hummingbird gardem at UC Davis. Renee C. Byer rbyer@sacbee.com

Bending around the university’s new School of Veterinary Medicine student services center, the crescent-shaped hummingbird garden borders walkways leading from the Arboretum Teaching Nursery to other garden areas off Garrod Drive on the UC Davis Campus. Volunteers planted hundreds of perennials, shrubs and trees from an extensive plant list.

Thirty of those hummingbird favorites will be featured in a new UC Davis Arboretum collection, appropriately called “Pollinator Plant List: Hummingbirds.” (Profiles of those bird-friendly flowering plants start in this Saturday’s Home & Garden section.)

The garden demonstrates how well those plants perform – not just in the landscape, but as hummingbird habitat.

“We’re trying to create a whole habitat for hummingbirds and pollinators,” Zagory explained. “Eventually, it will be part of our environmental gateway to campus.”

Aerial action is nonstop in the garden, entertaining diners in the nearby Scrubs cafe. In a dizzying display, the tiny birds dart from salvia to yucca, systematically sipping nectar.

“Hummingbirds have some kind of internal clock where they know how long it takes a flower to replenish its nectar,” Zagory said. “They know how long to wait before hitting the same flower again.”

Many of these hummingbird plants were tested in demonstration gardens inside the nearby Arboretum Teaching Nursery. Anna’s Hummingbird, the colorful birds with iridescent green and red markings, are year-round Sacramento Valley residents. Five other migratory species visit the valley and foothills on their flyways.

In addition to the birds, the new garden also attracts other pollinators such as carpenter bees and butterflies, Zagory said.

Nursery manager Taylor Lewis discovered many hummingbird favorites just by observation. “I see them every day, right outside my office window,” Lewis said. “They’re truly fearless.”

The tiny birds swoop over the nursery’s plant tables, looking for nectar-filled flowers. Feeders also have been set up to record hummer activity for bird researchers on campus.

During public plant sales (such as the season finale this Saturday), the hummers occasionally dive-bomb customers who attempt to purchase plants the birds like best. (Watch out around the California fuchsia!)

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A hummingbird dives from a nearby oak tree into the UC Davis hummingbird garden. Renee C. Byer rbyer@sacbee.com

“I know what the birds like,” Lewis said. “My favorites depend on the season; there’s something different every month. The important thing is to have something blooming every season, so the hummingbirds that stay here year round have nectar to eat.”

Along with nectar, hummingbirds also eat small insects for protein, Zagory said. They love aphids (another big plus for hummingbirds).

Hummingbird habitat needs a few specifics, she added. “They have to have a nearby tree or some shelter to fly into to protect them from predators. We have quite a few hawks out here and the hummingbirds need a place to hide.”

Hummingbirds like to perch on naked twigs – either in trees or shrubs, she noted. They prefer running water (such as from a fountain) to bird baths.

Most importantly, they need nectar. A hummingbird, which weighs less than nickel, needs to consumer double its body weight every day. That equals hundreds of flowers and aphids. Feeders help (especially in winter), but the birds prefer fresh flowers.

And red is definitely their favorite color.

“Birds see differently than we do,” Zagory said. “Red gets their attention. But once they discover a plant is a good nectar source, they’ll go to other colors, too. For example, they love the purple flowers on the Mexican white sage.”

Once hummingbirds find a garden, they provide endless entertainment, she added.

“I like to come out here and sit quietly, just observing – and trying to get a photograph,” Zagory said. “They forget about you after a while and just do their thing. They’re so much fun to watch.”

Debbie Arrington: 916-321-1075, @debarrington

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