GARDENING Events This Week IRRIGATION WORKSHOPS. Tucson-Pima Public Library (Bear Canyon). 8959 E. Tanque Verde Rd. Hands-on drip irrigation tips are offered on Saturday, August 24 from 9 a.m. to noon and information on irrigation timers is available from 1 p.m. to 3 p.m. Take one or both free workshops. Pre-registration is required. Call the Pima County Cooperative Extension at 622-7701.