The antonyms for the word "root up" could be words like plant, seed, sow, establish, or cultivate. These words denote actions that involve growing or planting something, as opposed to pulling it out or destroying it. When we root up a plant or tree, we are essentially uprooting it and removing it from its natural habitat, which can lead to negative consequences for the environment. Instead, by using antonyms such as plant or cultivate, we are promoting growth and nurturing the earth, which is essential for the well-being of our planet. Using these antonyms can help us cultivate a healthier relationship with nature and promote sustainability.