In observance of Earth Day, April 22, the Delaware Department of Natural Resources and Environmental Control encourages Delawareans to take part in the activities across the state.

— Party for the Planet Earth Day Celebration: 10 a.m. to 1 p.m. April 20, Brandywine Zoo, 1001 N. Park Drive, Wilmington. Learn what to do to help save species and make every day Earth Day during this special event. Free.

— Down to Earth Hike: 11 a.m. April 20, Cape Henlopen State Park, 15099 Cape Henlopen Drive, Lewes. Celebrate Earth Day with a hike searching for early spring plants and animals. Dress to explore outside. For ages 7 and older with an adult. Free. To register: 645-6852. Event free of charge.

— Earth Day Volunteer Project: 10 a.m. to noon. April 20, Killens Pond State Park, 5025 Killens Pond Road, Felton. Meet at the nature center and give back this Earth Day. Wear close-toed shoes, bring a water bottle and dress for the weather. Gloves and tools will be provided. Fre. Register at destateparks.com/volunteer. 900-1423.

— Earth Day Coast-to-Coast Clean-Up: 10 a.m. April 22, Delaware Seashore State Park, 25039 Coastal Highway, Rehoboth Beach. Help keep Delaware Seashore clean from coast to coast. Meet at the Indian River Life-Saving Station for a staff-led beach clean-up, then travel to Savages Ditch to clean up debris found in the salt marsh. Free. Must register: 227-6991.

— If These Trees Could Talk Walking Tour: 10 a.m. to 3 p.m. April 22, First State Heritage Park, Dover. Travel around The Green and experience some natural history, tree identification, and hear some of the events to which these trees have borne witness. Walking tours leave from the John Bell House on the hour and last approximately 45 minutes. Free. 739-9194.

— Earth Day Hike: 5 p.m. April 22, Trap Pond State Park, 33587 Bald Cypress Lane, Laurel. Join a park naturalist at the nature center for a hike to celebrate Earth Day. Free. 875-5153.

— Earth Day Hike: 5 p.m. April 22, Brandywine Creek State Park, 41 Adams Dam Road, Wilmington. A leisurely hike through the park. The meadows will be blooming and birds will be chirping. Hike will be approximately one hour. Event free of charge; park entrance fees in effect. 655-5740.

— Stroll with the Superintendent at Yorklyn Bridge: 10 a.m. April 24, Auburn Valley State Park, 3000 Creek Road, Yorklyn. Join Auburn Valley State Park Superintendent Laura Lee to explore the historic Yorklyn industrial district. Meet at the Yorklyn Bridge Trail parking lot. Free. 239-5687.

— Pre-Order Compost Bin Sale Distribution: 8 a.m. to noon April 27, Blue Hen Corporate Center, 655 S. Bay Road, Dover. DNREC’s Recycling Program is offering compost bins that can be pre-ordered online at a discount price of $50, half the retail price of the bins. The bins must be picked up by the purchaser at in Dover, Lewes and Delaware City. The Dover pickup is on April 27, while the other pickup locations are later in spring and early summer. enviroworld.us/delaware, 739-9403.

— Wild About Whales Earth Week Program: 11 a.m. April 27, DuPont Nature Center, 2992 Lighthouse Road, Milford. In honor of the 2019 Earth Day theme, “Protecting our Species,” learn about whales and how they are interconnected with many ocean species and ecosystems. Free. To register: 422-1329, lynne.pusey@delaware.gov.