Season-openers Get your trowels ready. The plant sale season kicks off this weekend with two big ones: The Friends School sale and the Minnesota Landscape Auxiliary sale. The Friends Sale is at the Minnesota State Fair grandstand and offers more than 2,300 varieties, including roses, vegetables, perennials, native wildflowers, shrubs, trees and rare plants. Hours are 9 a.m. to 8 p.m. Friday, 10 a.m. to 6 p.m. Saturday, and noon to 4 p.m. Sunday. Free admission. For a catalog, go to www.friendsschool plantsale.com or call 651-621-8930.

The arb plant sale features thousands of unique plants, difficult-to-find varieties, and University of Minnesota introductions, including a new pink shrub rose that blooms throughout the summer. Other sale stars are 'Liberty,' the "hosta of the year," and Brunnera 'Jack Frost,' the "perennial of the year." Herb bowls, fairy gardens and water garden plants are also for sale. Hours are 9 a.m. to 4 p.m. Sat.-Sun., 3675 Arboretum Dr., Chaska. Pick up a plant list at the Arboretum lobby desk for $1 per copy, or visit the arboretum's website (www.arboretum.umn.edu) to download a copy. Gate admission is $12 adults; ages 12 and under and members are free. Call 952-443-1400.

Hooray for public gardens The Minnesota Landscape Arboretum is celebrating National Public Gardens Day with free admission on Friday. Events include announcing the winner of the rose-naming contest, rose breeding program, a narrated tram tour along the Three-Mile Drive (small fee charged) and free guided tour of the nearby gardens. The arb also will give away sunflower seed packets, hats and T-shirts and will offer a public art mural activity on "What a Garden Means to Me." Call 952-443-1400.

Bonsai show The Minnesota Bonsai Society members will display their "trees in pots" from 10 a.m. to 6 p.m. Sat.-Sun. at the Marjorie McNeely Conservatory, 1225 Estabrook Dr., St. Paul. Free. Call 651-487-8201.