The messenger of spring comes from the Middle East, was once unimaginably expensive in Holland, is attacked by viruses that make it even prettier, and is still mysterious today.
Published: 04/03/2021, 11:45 PM—
–Cultivated tulips come in all colors. They are not only created by plant pigments, but also by the shape of the cells.
Foto: Getty Images
It is the warmth that gives the tulips the signal to sprout out of the ground and quickly stretch the noble flowers into the sun – just as it should be for heralds of spring. «As soon as temperatures of 20 degrees or more are reached, the tulips stretch like crazy»says Richard Immink from Wageningen University in the Netherlands. In contrast, the length of the day seems to be irrelevant for rapid growth – different from other plants. Experiments by Immink and his team have shown this.
So the heat is enough to grow, And this can even be observed with cut flowers: in the comfortably tempered living room, tulips protrude cheekily out of the vase. Their stems can stretch by several centimeters – and only by absorbing water. The special feature: the plant cells are surrounded by a stable but elastic cell wall and filled with water inside. If the tulip absorbs more water, the cells expand. This creates a pressure that can be far greater than the air pressure in a racing bicycle tire. Other cut flowers, such as roses, keep their original length because their stems are lignified.
