Ever wonder why flower bulbs don’t freeze in the ground over winter? While the rest of us are finding ways to keep warm, bulbs actually rely on the cold to initiate a biochemical process that allows them to flower come spring. The winter temperatures trigger their starches to convert into glucose, lowering the temperature at which water in the bulbs’ cells will freeze (much the same way salt on a sidewalk prevents ice from forming). As long as they are planted deeply enough, this chemical reaction keeps them safe and cozy, while the snow above provides a snug, insulating duvet. If only humans could enjoy such a comfortable deep-freeze.
And what if you didn't plant them deep enough?
Gardeners may no longer have to worry about how deep to plant flower bulbs this fall. According to a study from the Boyce Thompson Institute of Plant Research at Cornell University, some bulbs are actually able to adjust themselves to the correct depth. Apparently, when necessary, some bulbs form special contractile roots that pull them farther into the soil where growing conditions are optimal. It’s believed they are able to sense their depth based on light signals. Bulbs displaying this behaviour include tulips and lilies.
Photo: istock/Peter Burnett