Freezing food is common – but freezing plants could help save them from extinction. Across the globe, rare and endangered plants are disappearing, and many can’t be preserved through traditional seed banks. That’s where cryopreservation comes in.
This technique involves freezing tiny parts of plants at extremely low temperatures, keeping them alive in a state of suspended animation. Later, they can be thawed and grown again.
Take Magnolia wolfii, a tree discovered in a Colombian rainforest in 1985. Only six adult trees are known to exist. Its seeds can’t survive normal storage in seed banks – they burst. So scientists like Raquel Folgado, a cryobiologist at the Huntington Botanical Gardens in California, turn to cryopreservation instead. They remove shoot tips smaller than a grain of rice, treat them with protective chemicals, and freeze them. Each frozen tip holds the potential to grow into a new plant.
Why is this important? Over a third of critically endangered plants either don’t produce seeds or have seeds that can’t survive long-term storage. Yet fewer than 1% of these plants are currently cryopreserved. Each species requires a unique freezing method, making the process costly and slow.
There’s also a major challenge: thawed plants still need a healthy ecosystem to survive. If the environment they came from no longer exists, bringing them back won’t work. That’s why scientists emphasize a two-part strategy – protect natural habitats now and freeze what we can for the future.
Cryopreservation has already helped save banana, potato, and blueberry species used in breeding stronger crops. One day, it may help bring back plants like Magnolia wolfii. Thanks to these “ice gardens,” lost pieces of our planet may get a second chance.