Roman Ivannikov has spent around 30 years pampering orchids, azaleas and figs at Ukraine's National Botanical Garden, but power cuts triggered by Russian strikes are threatening to freeze his cherished collection of tropical plants.
Moscow has been pummeling Ukrainian energy sites with drones and missiles, plunging thousands of households into darkness during the harshest winter since it started its invasion four years ago.
The almost-daily barrages, paired with the cold snap, have put lives at risk and created an unprecedented threat for Ivannikov's pride and joy: a collection of almost 4,000 species.
"Our children grew up on the paths of this garden. We have poured our lives into this," Ivannikov, 51, told AFP, struggling to fight back tears.
The temperature in the garden's main greenhouse was 12C.
"It's not even the lower bound of normal," Ivannikov said.
The temperature dipped even lower on four nights over recent weeks, when the heating cut off entirely.
Wearing a thick navy jacket over a wool sweater, Ivannikov, the head of the department of tropical and subtropical plants, picked up a leaf that had just come rustling down.
"You can see how many fallen leaves there are... Perfectly healthy leaves that could have kept feeding the plant and functioning for months are falling down," he said.
The plant, he explained, was optimizing energy needs and shedding part of its leaves in the lower tiers so it can keep the leaves at the top and "survive in these conditions".
He, fellow staff and scores of volunteers were shuffling between tasks like firing up stoves and spreading protective covers on a collection of smaller plants, like orchids.
Volodymyr Vynogradov, 66, has signed up to help cut firewood used to heat the greenhouses.
"There needs to be heating for the azaleas," he told AFP, his cheeks rosy from cold and a pile of split logs scattered around.
"Physically, it's a little bit of a warm-up... That's why I decided to help somehow. For myself and for the sake of flowers."
The garden's collection has been laboriously reassembled after it had perished during World War II -- through decades of purchases, exchanges and numerous scientific missions that took Ivannikov's senior colleagues across several continents.
They "used to go to places and bring back plants from areas where those forests are no longer there", making those replanted at the Kyiv garden susceptible to "irrecoverable losses".
"Those plants have been preserved with us, and that underscores their uniqueness: if we lose them, we won't be able to restore them," Ivannikov said.
Individual specimens have already wilted, but the scale of damage is impossible to assess -- the destructive impact of the cold could only start to show in weeks or even months to come.
"Flowering intervals will change, plants will bloom but won't be able to set seed for a year or two. Or, for example, they'll set seed, but it won't be viable -- it will be dead," Ivannikov, who is trying to stay hopeful, said.
"We just have to hold on until summer, until spring -- make it through however many days are needed."
His dream, he said, is to create a "large national bonsai collection", something he had already begun laying the groundwork for.
The institution meanwhile offers organized tours and works with military servicemen and displaced Ukrainians who find solace in gardening work.
"They feel alive and want to see what comes next. They see a future, they want to keep living -- and that's our mission."
