Researchers can now tell when Earth's last plant will die; reveal the planet's surprising green future

Picture a world without the lush forests, colorful blooms, or blades of grass. The planet that once was blanketed by greenery throughout millions of years could eventually become a lifeless Earth in which not even the most resilient plants will be able to thrive. However, is it something that can happen suddenly and unexpectedly as an impact from outer space or any other disaster? Most likely, not.

The study examines how the Sun's gradual brightening, alongside changes in atmospheric carbon dioxide, could eventually limit plant life on Earth. In fact, according to one of the studies conducted in 2026, scientists tried to determine how much time our vegetation could survive with those conditions slowly changing.

The Sun is slowly changing Earth's future

The Sun becomes increasingly bright as it ages, meaning there is more energy that comes into Earth. After a long time, such increased energy might make Earth become hotter than is sustainable for plant life.

On the other hand, Earth's geological carbon cycle can affect the availability of carbon dioxide within the atmosphere. Plants depend on this gas for photosynthesis, using sunlight to convert carbon dioxide and water into sugars that fuel their growth.

The scientists Jacob Haqq-Misra and Eric Wolf of Blue Marble Space and the University of Colorado Boulder examined how both those factors might affect the Earth's vegetative biosphere in the future in their article Maximum Lifetime of the Vegetative Biosphere published in Journal of Geophysical Research: Atmospheres in 2026.

Two possible futures for Earth's vegetation

Using a three-dimensional climate model, the researchers examined different combinations of rising solar energy and changing atmospheric carbon dioxide. They considered two possible scenarios.

In one, geological weathering removes carbon dioxide from the atmosphere while helping keep temperatures relatively stable. Under the conventional threshold of 10 parts per million of carbon dioxide, the researchers estimated that the limit for C4 photosynthesis could arrive in about 1.35 billion years. However, certain plants may survive at lower concentrations, potentially extending the biosphere's lifetime to around 1.84 billion years.

In the second scenario, carbon dioxide remains relatively stable while temperatures rise as the Sun brightens. Under these conditions, most land plants could become unable to survive after approximately 1.68 billion years, with conditions eventually becoming too hot for all land plants around 1.87 billion years.

These figures are model-based estimates, not fixed deadlines for every plant species.

Could life continue after the last plants disappear?

Implications go far beyond forests and vegetation. The projected timeframe by the authors is to the point when Earth could possibly have no more oceans because of increased solar radiation and become less and less suitable for the existence of terrestrial life as it exists today.

However, that would not automatically imply that every living being on Earth will perish at once. There would be microbial organisms capable of surviving in certain conditions.

The researchers note the possibility of evolution and technology in preserving Earth's biosphere. Still, neither can be predicted for sure.

The findings concern Earth's distant future, not an imminent extinction event caused by today's climate change. They offer a reminder that the planet's habitability depends on a delicate relationship between its atmosphere, geology and star—and that even this relationship will not remain unchanged forever.