Trop picks: Tulips
The Aksu-Zhabagly reserve in Kazakhstan is home to T. greigii and T. kaufmanniana (aka the “water lily tulip”), two species of wild tulips from which over five hundred species of cultivated tulips are said to originate.
T. Kaufamanniana
Both species are named after nineteenth century Russian bureaucrats, when Imperial Russia was spreading her tentacles eastward. Botanists and plant hunters often followed in the wake of military campaigns.
You’d think—or at least I do, as someone with warm weather in my bones—that the climate in this part of the world isn’t exactly conducive to flowering plants. Bitterly cold winters, dry and desert-like conditions, and short, scorching summers.
But tulips have a secret weapon: their overwintering bulbs, which store nutrition and energy underground during the cold months. In T. kaufmanniana, the bulb actually grows away from the sun in the winter, burrowing deep in the soil where it’s warmer.
These nifty evolutionary adaptations so enthralled Darwin’s grandpa Erasmus that he wrote a poem about them for “ladies and other unemployed scholars” (such as yours truly):
When o’er the cultured lawns and dreary wastes
Retiring Autumn flings her howling blasts…
In withering heaps collects the flowery spoil.
And each chill insect sinks beneath the soil.
Quick flies fair Tulipa the loud alarms,
And folds her infant closer in her arms;
In some lone cave, secure pavilion, lies,
And waits the courtship of serener skies.
In the winter, Mother Tulipa—safe to say that the Darwin family’s talents lay not in poetry—also wraps a nice warm cloak of hair around her baby—the tulip flower, leaves and all, in miniature—within the bulb.
Some tulip bulbs are so hairy, tufts of hair peek through the thin papery tunic that covers the bulb. There’s a depilation joke in there somewhere.
(You know what else has a bulb, a tunic and grows wild in the Central Asian steppes? Onions. There was a time when taxonomists thought tulips and onions were related.)
Tulips actually need cold weather to flower. Through a process known as vernalization, the cold temperatures set off a reaction that gradually represses a gene in the tulip that impedes stalk elongation (sort of like slowly taking your foot off the brakes). Once spring arrives, the stalk is long enough and rearing to go, popping up above ground along with the flower.
More curiously, a tulip that has been exposed to a particularly harsh winter will “remember” this fact (the cellular memory in tulips—like in humans—is regulated by a substance known as chromatin) and do what it needs to--that is, flower-- to ensure its survival as soon as more favourable conditions set in. The longer and harsher the winter, the earlier the tulip flowers.
