• The Spring Celebration Festival is Saturday at the Utah Botanical Center in Kaysville. (It's part of the complex that includes the Utah House). Classes are from 9 a.m.—2 p.m. at the Botanical Center's greenhouse, 150 East Sego Lily Drive (725 S. Frontage Road). The class schedule: Small Space Gardening, 9 a.m.; Pruning Grapes & Raspberries, 10 a.m.; How to Have a Great Landscape with Poor Soil, 11 a.m.; Landscape Design, noon; and Designing Fabulous Spring Perennial Gardens for Utah, 1 p.m. Get more information at utahbotanicalcenter.org/

• The Bonsai Club of Utah will hold its annual spring show at Red Butte Garden, April 29-May 1. Hours are 9 a.m.-7 p.m April 29 and 30; and 9 a.m.-5 p.m. May 1. Admission is included in garden admission, except for Friday, when admission to the garden and the show is free because it's Arbor Day. Demonstrations will take place throughout the day Saturday and Sunday. For information on the show or club meetings, contact club president Aaron Penrod at 801-455-5423 or publicity chairman Yvette Ungricht at 801-278-9316.

• Red Butte Garden will host an Arbor Day Celebration Friday, April 29, from 9 a.m.-3 p.m. Activities include the State Arbor Day Ceremony and poster contest award ceremony (10 a.m.) as well as activities for youth and families to explore the world of trees. Admission to the garden is free that day.

• Meet Red Butte Garden's conservation biologist Jena Lewinsohn and learn about Utah's rare native plants and endangered plants. April 30, 10 a.m.-noon. Admission free, and no registration is required.

• Red Butte Garden will host a lecture by artist Robert Wick, who will introduce his work and discuss how he incorporates living plants with his sculptures as a symbol of "our effort to sustain life on this planet;" April 30, 11 a.m. Information:581-6464 or online at www.redbuttegarden.org.