ITHACA, NY -- Confused about the right planting depth for flower bulbs? Trust the bulbs! Researchers have discovered that some flower bulbs are actually "smart" enough to adjust themselves to the right planting depth. A recent study published in the Journal of the American Society for Horticultural Science proved that bulbs can adjust their planting position by moving deeper into the ground, apparently in search of moister, more conducive growing conditions.
According to Dr. A. Carl Leopold, William H. Crocker Scientist Emeritus at The Boyce Thompson Institute for Plant Research at Cornell University, when gardeners plant tulips or lilies too shallowly in their gardens, the bulbs will respond to the shallow conditions by literally "pulling" themselves down into deeper ground. "One doesn't think of plants moving, and especially moving down into the ground, but our research proved that this movement occurs.", explained Leopold.
Leopold and the late Dr. Modecai Jaffe had studied plants for decades, but had never focused on bulb movement in soil. The duo was interested in working on the physiology of "contractile roots", or those roots that are responsible for bulbs' movement. Explained Leopold, "Negative growth is very rare in plants, and the sort of contractile proteins that are so well known to drive contraction in animal muscles do not occur in plants. We selected this work as a divergence from the usual studies of growth, and introduced the idea of contraction." He added that hundreds of books have been written about plant root growth, but none mention this phenomenon of negative growth.
The study focused on the "Nelly White" variety of Easter lily. Contractile roots were found to respond to light signals perceived by the bulb. Exposure to certain types of blue light forced new contractile roots to be formed on the bulbs and helped initiate the remarkable bulb movement.
Further explaining the study, Leopold noted that
|Contact: Michael W. Neff|
American Society for Horticultural Science