Foster Botanical Gardens, 522-7060: Spring plant sale, 9 a.m. to 4 p.m. May 10. Sponsored by the Friends of Honolulu Botanical Gardens. Free. Call 537-1708.

Halawa Xeriscape Garden, 527-6113: "Native Plant Propagation Class" by Mary Wickenden, 10 a.m., May 10. Registration required.

Free admission to garden of dry-land plants at Halawa Industrial Park 10 a.m. to 2 p.m. Saturdays and Wednesdays. Call 527-6113 for an appointment.

Hawaiian Botanical Society, 3190 Maile Way, 956-3925: David Hopper of the U.S. Fish and Wildlife Service will speak on "Pollination of Hawaiian Plants by Hawaiian Bees," 7:30 p.m. May 5, University of Hawaii-Manoa, 3190 Maile Way, St. John Hall 011.

Ho'omaluhia Botanical Garden, 233-7323: Volunteer training program for people interested in becoming nature tour leaders, 9:30 to 11:30 a.m. Saturdays, through May 17.

Orchid Society of Manoa, 537-3071: Orchid show and plant sale, 8:30 a.m. to 6 p.m. tomorrow and 8:30 a.m. to 4 p.m. Sunday Noelani School Cafetorium, 2655 Woodlawn Drive. Saturday, Edwin Oka will give tips on general orchid culture, 10 a.m.; Clifford Mito on dendrobiums (hono hono) at 2 p.m. Sunday, Wally Nakamoto talks on cattleyas, 10 a.m. Call 537-3071.

Pearl City Bonsai Club: Bonsai exhibit and plant sale, 9 a.m. to 3 p.m. tomorrow, Pearl City Hongwanji, 858 2nd St. Bonsai demonstrations at 10 a.m. and 12:30 p.m. Call 262-5873.

Waipahu Orchid Association, 453-6566: Orchid-care demonstration and plant sale, 10 a.m. to noon May 10, Pearl City Library meeting room.