Why we should plant ocean trees to reverse climate change

Elsa Monteith

A coastal realm of roots and branches, mangrove forests are fast becoming a lifeline for the mission to reduce carbon emissions.

Image © Octavio Aburto

Elsa Monteith

Image © Octavio Aburto

Green trees planted firmly in the deep blue

Spanning extensive stretches of shore across the equatorial belt, ocean trees, called mangroves, cluster on the perimeter of tropical and subtropical coastlines. A marshy meeting of land and water, these dense tangles of ocean trees grow in the wetlands of five different continents and offer a canny solution to the climate crisis in more ways than one.

The Gambia · Curioso Photography

A living, breathing network of tree trunks and roots

Ocean trees make up one part of the “big three” of marine ecosystems, together with salt marshes and seagrass. A naturally innovative “carbon sink,” they absorb carbon dioxide from the air and then cleverly store it in their web of roots and branches. Their remarkable aptitude for absorbing and storing carbon is estimated by the UN to reach over 4 billion tons, equivalent to the combined annual emissions of the U.S. and China.

Galyna Andrushko

Protective force of nature

Mangroves are salt-tolerant trees, flourishing where freshwater intermingles with seawater and sediment. Over 80 different mangrove species nourish a rich biodiversity of sea creatures whilst shielding and stabilizing the shore. Ocean trees are five times more cost effective than human-made infrastructure designed to protect coastal communities, reducing wave heights by up to 60% and tsunami flood depth by 30%.

Raja Ampat, West Papua · Shawn Heinrichs

A future in the hands of mangroves

Restoring, replanting, and replenishing our ocean forests will change more than just the scenery, it will nurture a bountiful underwater ecosystem and help reverse climate change. Whilst mangroves make up around only 1% of forested land globally, they can store four times more carbon than other tropical forests, locking it in the soil deep below their roots for millions of years.

Mahajunga, Madagascar · Eden Reforestation

The pros and pitfalls of planting

An invaluable resource above and below the waterline, ocean trees need protecting. The question is, does mangrove planting help? Every project is different, and unfortunately some do fail because of a lack of proper risk management and/or mangrove restoration expertise, for example. With the right checks and balances, however, it’s possible to supersize our impact for the planet by planting mangroves.

Eden Reforestation, one of our partners planting mangroves on behalf of Only One members, has an impressive seedling survival rate exceeding 80%. Between years three and five of growth, the young mangrove trees start producing their own propagules (new seedlings), resulting in a forest with a rapid cycle of natural regeneration. Each tree planted generates between 1.5 and 5 times more trees.


Ocean trees are undoubtedly our hidden heroes tackling the climate crisis.

Equipped with this knowledge, we can all take action to advance mangrove restoration and protection. Members of Only One are supporting two types of mangrove projects: planting 1,000,000 trees in Kenya and helping protect 2,000+ hectares of pristine mangrove forest in Cambodia. Saving the ocean and fixing the climate can truly start with just one seedling!

Matt Curnock / Conservation International

How you can help

1 Start planting ocean trees today on Only One with a monthly membership. Each month, you’ll plant between 10 and 100 mangroves! 2 Share this article with your friends and family to spread the word about extraordinary ocean solutions like mangrove planting and restoration.


Elsa Monteith

Writer, Driftime

Writing from the sunny shores of Brighton in the UK, Elsa Monteith lends her hand to words with purpose and impact, working with a selection of like-minded organizations with a shared interest in planet, people, and progress.

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