The arboretum’s plant sales are a lot like the preserve’s signature oaks — growing taller and sturdier by the year.

Friends of the UC Davis Arboretum started with iris corms in 1973, digging them up in the arboretum and selling them for 10 cents each, at a table in Davis’ Central Park, and raising $206 the first day, according to an article in the winter edition of the Arboretum Review.

In 1975, the friends organization launched its annual Plant Faire — and since then, this sale and others have grown into a widely anticipated series of events for home gardeners throughout northern California and beyond.

The arboretum gets a jump on spring with its annual Members-Only Plant Sale on Saturday, March 12. Others are scheduled April 2 and 30, and May 14, all Saturdays.

“These sales allow arboretum horticulturists to distribute beautiful, environmentally-friendly landscaping plants to the public,” the Arboretum Review stated.

The sales also provide an important source of operational funding for the arboretum — so much so, that in 2009 the university recognized the Friends of the UC Davis Arboretum as a Chancellor’s Laureate, for donating more than $1 million in accumulated gifts.

This year the friends organization celebrates its 40th anniversary — 40 years during which the members have given time, energy, money and enthusiasm to support the arboretum’s development into a world-class botanical treasure for the university as well as for the public.

“The arboretum’s programming, staffing and plant collections would not have been possible without this support,” the Arboretum Review stated.

The 40th anniversary makes this weekend's Members-Only Plant Sale even more special, a time “to honor our ‘best friends,’” as the Arboretum Review headline declared.

Everyone is welcome to attend. If you are not already a “friend,” you can join at the gate. One-year memberships: $15 student, $40 individual, $60 family-household.

All members receive a free plant (one per membership), plus a 10 percent discount.

The sale is scheduled from 9 a.m. to 1 p.m. at the Arboretum Teaching Nursery. It is on Garrod Drive, off La Rue Road (look for the nursery on the left-hand side, just past the Unitrans bus yard and across from the Veterinary Medical Teaching Hospital). The program includes music, refreshments and children’s activities, as well as free, expert gardening advice.

The organizers said the March 12 sale and the others this spring will feature the Santa Margarita foothill penstemon (Penstemon heterophyllus Margarita BOP), a native penstemon well suited to a garden environment.

The Margarita BOP is one of the Arboretum All-Stars, a tested group of 100 reliable, easy-to-grow plants for most Cali¬fornia climate zones.

On the Web

UC Davis Arboretum

Arboretum All-Stars

More at the arboretum

Folk Music Jam Sessions — Pull out your fiddles, guitars, mandolins, penny whistles, pipes, flutes, squeezeboxes — you name it! — and join your fellow musicians during the lunch hour for a little bluegrass, old-time, blues, Celtic, klezmer and other world music. All skill levels welcome. Listeners, too! Noon Friday, March 18, Wyatt Deck.

Spring in the Native Plant Garden — Learn about local native plants and see the native plant collection in full bloom. 2 p.m. Saturday, March 19, Buehler Alumni and Visitors Center.

Plant sale preview — See garden plants that will be available at spring plant sales April 2 and 30, and May 14. Preview, 2 p.m. Saturday, March 26, Arboretum Teaching Nursery.

Spring in the Storer Garden — Gorgeous spring bloom in this demonstration garden of drought-tolerant, low-maintenance perennials and flowering shrubs. Many of these plants will be for sale at the spring plant sales. 11 a.m. Sunday, March 27, gazebo.

All programs are free and open to the public; plant sale admission is free, except for the members-only sale. More information: (530) 752-4880 or arboretum.ucdavis.edu (for directions, click on “Plan Your Visit”).