• The 25th annual Cardboard Boat Regatta, benefiting the educational programs of Arlington’s River Legacy Living Science Center and Parks, will be 9 a.m.-4 p.m. Saturday, April 26, at Six Flags Hurricane Harbor. $8. http://tinyurl.com/qhyu38d
• The 60th annual Flowercade, presented by the Garden Club Council, Rose Society and Iris Society, will be noon-5 p.m. Saturday, April 26, and Sunday, April 27, at the Fort Worth Botanic Garden Center, 3220 Botanic Garden Blvd. The event features flower design, horticulture and educational displays. Gardening items, hanging baskets and other plants will be sold 9 a.m.-5 p.m. Saturday only.
• See the “Lennox Woods: The Ancient Forest” art exhibit through May 8 at the Botanical Research Institute of Texas, 1700 University Drive, Fort Worth. The exhibit is a multiyear project by artist Deborah Paris involving one of Texas’ most pristine old-growth forests, located in Red River County. For hours, visit brit.org.
• Learn all about hibiscus, the topical shrub with impressive blooms, during a free clinic at 10:15 a.m. Saturday, April 26, at all Calloway’s stores. www.calloways.com.
• A spring trail series continues with a hike to Greer Island, 1:30-3:30 p.m. Saturday, April 26, at the Fort Worth Nature Center and Refuge, and on Sunday, April 27, the series continues with a hike to Canyon Ridge. You can join refuge naturalists for a leisurely wildflower survey 1:30-4 p.m. Both events are free with admission ($2-$5). Friday, May 2, join a naturalist for an “early birds” hike, 8:30 a.m. Meet at the Nature Center. It’s free with paid admission, too. 9601 Fossil Ridge Road, Fort Worth. 817-392-7410; www.fwnaturecenter.org.
• Get your gardening questions answered any weekday with a call to the Tarrant County Master Gardener Association help desk, 817-884-1944. Call 8:30 a.m.-4:30 p.m. Monday-Friday with your horticultural questions.
• Johnson County Master Gardeners answer gardening questions and give horticultural advice 9 a.m.-4 p.m. Fridays. Simply call the Johnson County Extension Office at 817-556-6370 and ask to speak to a master gardener. If a solution can’t be provided immediately, your question will be researched.
Mark your calendar …• For the Colleyville Garden Club’s 21st annual Garden Tour Promenade, 11 a.m-4 p.m. May 4. The tour includes large and small gardens, including a wedding garden, and Texas native and adapted plants. Tickets are $12, $15 the day of the tour. Find them at Foreman’s and Market Street in Colleyville, Sew-It-Up and Callaway’s in Hurst, Blooming Colors and Marshall Grain in Grapevine, and Callaway’s in Southlake. colleyvillegardenclub.org.
• For Prairie Day at the Botanical Research Institute of Texas, 8 a.m-1 p.m. May. 3. Activities include a prairie dog naming contest — names can be submitted in advance on BRIT’s Facebook page https://www.facebook.com/BRITorg or via Twitter at https://twitter.com/BRIT_org. Use #BRITPrairieDay — arts and crafts, music, food trucks, a farmers market and more. Exhibitors include Log Cabin Village, Texas Bluebird Society, Tarrant County Water District and more. 1700 University Drive, Fort Worth. brit.org
• Texas A&M Agrilife Extension’s EarthKind modular horticulture and master gardener classes will run on occasional Saturdays through December. The classes, which cover botany, horticulture and plant propagation, will be in Fort Worth and other cities in North Texas. Space is limited, so pre-registration is recommended. For more information, call 817-884-1944 and ask for Steve Chaney, or visit http://tarrantmg.org for the schedule.