* Today: Talk on new camellias from China, 7:30-9 p.m. at Descanso Gardens, 1418 Descanso Drive, La Canada Flintridge, (818) 952-4401. $13. Reservations required.
* Saturday: Demonstration on rose care (10-11:30 a.m.) and pruning (noon-1 p.m.), Fullerton Arboretum, 1900 Associated Road (at Yorba Linda Boulevard), Fullerton, (714) 278-3404. $7. Will be postponed until Jan. 30 if it rains.
* Saturday: Workshop for children (ages 6 and older) on building their own garden weather stations, 9-11:30 a.m. at the Huntington Botanical Gardens, 1151 Oxford Road, San Marino, (626) 405-2272. $10; includes all materials plus admission for one accompanying adult. Reservations required.
* Saturday-Sunday: Camellia show and sale, 1-5 p.m. Saturday, 10 a.m.-4 p.m. Sunday at the South Coast Botanic Garden, 26300 Crenshaw Blvd., Palos Verdes Peninsula, (310) 544-1948. $5, adults; $3, seniors and students; $1, children.