Many people were busy this week planting trees or other land-based plants in celebration of Earth Day. Earth Day comes at a time of year when the snow (hopefully) has melted and the ground has thawed enough to do some planting and to uncover dormant plants to prepare for warmer weather.

But spring isn’t just when lawns and parks begin to turn green for the season. It’s also the time when underwater vegetation is fully “leafing” out. However, while land-based plants are just beginning to get their leaves, many of Maine’s seaweeds are ready for harvest come spring. This year’s Earth Day coincides with a celebration of that harvest — Maine Seaweed Week.

This year marks the seventh annual Maine Seaweed Week, which claims the distinction as the biggest seaweed food and drink festival in North America. It begins April 25 and continues through the weekend until the end of next week, ending May 4. The event is hosted by Portland’s Heritage Seaweed, a shop featuring all things seaweed; Maine Sea Grant; and the Maine Seaweed Council. There are details about events as well as a list of participating restaurants and galleries and links to many seaweedy recipes at seaweedweek.org.

While many of the events are located in the Midcoast or Portland area, the event is statewide and includes art exhibitions and cooking classes as far away as Ellsworth. Food and drink are at the center of much of what is planned for this week, with restaurants offering dishes ranging from Standard Baking Company’s seaweed croissants to Belfast’s Marshall Wharf Brewing Company’s seaweed saison brew. Those are just a couple of the more than 70 participating restaurants and eateries. For those not interested in consuming seaweed, there are also plenty of other events to enjoy.

There are educational events like seaweed identification workshops, art demonstrations like making your own kelp prints, along with artists’ exhibitions at a variety of art galleries. There is also a marketplace of more than 40 different vendors showcasing products made with or inspired by seaweed, including everything from jewelry to chocolate to pet food. The marketplace is part of the culminating day, Seaweed Saturday (April 26), which will be held from 11 a.m. to 4 p.m. at the Gulf of Maine Research Institute. It is free and open to the public. In addition to the marketplace, there will be educational panel discussions, cooking and art demonstrations, and kids activities including an interactive kelp line and touch tanks. Food trucks will also be parked outside with picnic space on the waterfront lawn.

Maine is home to an abundance of seaweed species ranging from the smaller red varieties like Irish moss (Chondrus crispus), which can be used as a thickener in desserts like puddings; to the more delicate Dulse (Palmaria palmata), which can be smoked and fried up as a bacon-like topping; to the larger brown species like winged kelp (Alaria esculenta) and sugar kelp (Saccharina latissima), which can be used in broths or dried and powdered into seasoning blends, among many other uses. Many of these species can be cultivated or wild harvested. In addition to being nutritious food sources, seaweeds are incredibly valuable to other marine life in their production of oxygen, role as a food source and as habitat. They also absorb a large amount of carbon dioxide as they photosynthesize, which helps to reduce the acidification in ocean waters — something that is problematic for many species.

So, while celebrating Earth Day this week, consider not just what you can do on the land-based side of things but also what makes an impact in the coastal environment. Supporting and celebrating the local seaweed industry is a fun and easy way to make a difference.

Susan Olcott is the director of strategic partnerships at Maine Coast Fishermen’s Association.