Every autumn, millions of little orange suns emerge from the dark green foliage of small trees along the Black Sea coast of the Caucasus. These are the ripening citrus fruits. However, Adjara and Abkhazia still can’t supply enough mandarins and oranges to satisfy the entire country. And in regions like Moscow or Murmansk, you can’t plant a mandarin tree; it would perish at the first frost.
Scientists have long pondered the question: why do trees freeze? And they have found an answer.
A birch branch was placed in a special chamber and cooled to minus 100 degrees Celsius. When it was brought into the laboratory and placed in a jar of water, it sprouted green leaves. An even greater cold—minus 253 degrees Celsius—was endured by a blackcurrant branch. This suggests that trees can fight against frost on their own. They just need a little help to enhance their frost resistance. This means ensuring that the cell walls of the plant are permeable to water. Biologists are confident that modern chemistry can tackle this challenge.
And then, citrus and peach orchards could thrive even along the shores of the Arctic Ocean!