During the winter, trees lay dormant, covering their most vulnerable growing tissue with protective buds. In spring these buds burst open to reveal growing shoots and blossoms.
But how does the tree know when to do this?
How do trees and plants know when spring arrives?
Plants and trees contain a light receptive protein called phytochrome. This pigment enables a growing organism to detect shortening nights giving the signal to burst bud and grow.
If the days are too cold the plant will hold back, waiting until this risk has passed. For flowering plants, such as thale cress, henbane and certain types of broccoli, differences in temperature give the plant the message that spring is on its way.
These specifically need a period of cold, followed by a period of warmth, sometimes with changes in humidity to give the plant the signal to begin the processes which will lead to blooming.
Our changing climate has brought unpredictable weather patterns and many plants have flowered during the wrong time of year.