Here’s a plan for Saturday, the fifth of May: Buy a bike at a bargain price; pedal on over to the California Raptor Center for its spring open house, or to the arboretum’s Storer Garden for the Romance and Legend rose tour; get your design on at the Oh! Design open house; and celebrate Cinco de Mayo at La Gran Tardeada. (Plus a bonus event for good measure.)

1. Bike auction — Abandoned and unclaimed bicycles are going up for auction once again. The bike preview starts at 8 a.m., and the sale at 9 — in the west entry parking garage (so this event goes on, rain or shine).

The Bicycle Program holds auctions every fall and spring. Prices in the most recent sales averaged $30 to $40, said David Takemoto-Weerts, coordinator of the Bicycle Program.

More than 400 bicycles are typically on the auction block: all sizes and types — cruisers, mountain bikes, road bikes, BMX and even a few children’s bikes — with most in the “fixer-upper” category, Takemoto-Weerts said.

The sale continues until all of the bikes have gone up for bid. The Bicycle Program accepts cash, check or major credit card with proper identification. Parking is free.

2. California Raptor Center — A Hawk Walk is only the beginning of a great day when the center presents its annual spring open house.

Meet at the gate at 8 a.m. for the Hawk Walk (and bring binoculars). Otherwise, drop by from 9 a.m. to 2 p.m. for the open house; the museum will be open, and special presentations on raptor biology and ecology are scheduled for 10 a.m. and 2 p.m.

The Hawk Walk and the open house are free, but, according to a news release, donations will be gratefully accepted during this time of budget cuts.

The center, a program of the School of Veterinary Medicine, provides care for injured raptors (eagles, hawks, vultures and owls), rehabilitating them and, whenever possible, releasing them back to the wild. Birds that cannot be released are trained to take part in the center’s education program.

Directions: Take the UC Davis exit from Interstate 80 and turn south on Old Davis Road. Cross the railroad tracks and continue until just before the Putah Creek bridge. Turn left onto the paved levee road. Follow it for two-tenths of a mile and keep on the pavement as the road veers left, taking you down off the levee. Then make a quick right turn into the free parking area.

3. Rose Day — A combination workshop and two-day plant sale, open to the public both days. Each person attending the workshop will receive a free 4-inch Cinco de Mayo rose, recognizing the fact that this year’s Rose Day, the fifth annual, falls on Cinco de Mayo.

The workshop opens at 8 a.m. with the Romance and Legend rose tour (in English and Spanish) in the arboretum’s Storer Garden. (This tour is also open to nonworkshop participants, free of charge.)

The workshop continues at Foundation Plant Services for breakout sessions with rose breeding experts Jacques Ferare and James Sproul, followed by lunch. The program concludes with two tours: the All-American Rose Selection Testing Garden and the Foundation Plant Services Rose Collection.

The plant sale runs from 2:30 to 5:30 p.m. Saturday, May 5, and noon to 5 p.m. Sunday, May 6. Roses will sell for $25 per plant, $22 each for five or more, $18 each for 10 or more — with proceeds benefiting horticulture education at UC Davis.

Tours of the eight-acre rose collection will be offered from 2:30 to 3:30 p.m. Saturday, May 5, via shuttle bus from the plant sale.

Registration and more information.

4. Oh! Design — “Reconnect with faculty, staff, students, friends and alumni, visit our new building; and celebrate our departmental status,” the invitation reads.

The new department is the Department of Design, and the event is an open house, from 1 to 5 p.m. in Cruess Hall. The invitation states: "We will remember Walker Hall and the beginnings of our department, showcase the work of students, faculty and alumni, celebrate our accomplishments, and look forward to the continued growth of design at UC Davis."

The program includes guest speakers and alumni speakers and a timeline of the department's history, and provides an opportunity to network with professionals, and meet faculty and staff, past and present. Refreshments with a Cinco de Mayo theme will be served, the organizers said.

Studios and labs will be open, along with the Design Museum (the open house comes on the last day of Design by Design — the annual exhibition of students' work in a juried competition).

5. La Gran Tardeada — A family event that comes at the end of La Raza Culture Days. La Gran Tardeada, from 11 a.m. to 6 p.m. on the Quad, features entertainment, Children’s Fair, Health Fair and Immigration Clinic, and food booths.

The Cuauhtemoc Run, hosted by MEChA, starts at 7 a.m. near the Music Building, along the arboretum waterway east of Mrak Hall. Participants are welcome to run or walk 5 or 10 kilometers around the arboretum.

Bonus event: Benefit concert at the Mondavi

The Mondavi Center for the Performing Arts is the venue for a May 5 benefit concert by classical pianist Tien Hsieh, in support of Medicos: The Kenya Project, an exchange program involving the UC Davis and University of Nairobi medical schools.

Each year, UC Davis sends students to Kenya, where they work with University of Nairobi students and physicians in urban slums and rural villages, providing free care, especially to women and children who have been affected by HIV and AIDS. Several University of Nairobi students then come here, to work on rotations at the UC Davis Medical Center — and the concert will help pay for their trip.

Other proceeds will be used to buy medications to be used in Kenya, and to hire health workers there — physicians, medical officers and pharmacists.

The Hsieh concert, featuring music by J.S. Bach, Lizst and Mozart, is set to take place in the Mondavi Center’s Vanderhoef Studio Theatre. A reception and silent auction are scheduled for 3:30 p.m., and the concert at 4:30.

Hsieh is a critically acclaimed pianist who has won several international competitions and performed across the United States and around the world. She is a recipient of the Roy M. Rubinstein Award from the Manhattan School of Music, and the Li-Ching Cultural and Educational Foundation Grant.

Tickets ($100 each or $25 for students) are available through the Mondavi Center box office: online; by telephone, (530) 754-2787 or (866) 754-2787; or in person, noon to 6 p.m. Monday through Saturday. For more information, or to reserve tickets, send an e-mail to medicoskenya@googlegroups.com.