Underground Happenings
Our plants are, by and large, in a dormant mode.
I was curious about that phenomenon so I talked to Dr. Michael Campbell
at Penn State-Erie. He told me about an
amazing time-keeper present in the plants' leaves and buds.
Last fall and winter, they were signaled by this chemical receptor (phytochrome)
in response to the changes in light
length and intensity to begin preparing for winter and shutting down.
The coming of winter involves intense activity that is not necessarily
apparent to the average gardener. Just as bears
(and certain garden writers) lay on additional body fat for winter,
plants manufacture and store extra sugar, proteins
and fats to facilitate their survival in the winter months and to provide
energy for spring.
Only after the plant has accomplished these survival tasks does it begin to slow down. Leaves drop and stems stop their growing. The above ground portion of herbaceous perennials dies back. Annuals and second year biennials do too, of course, but they really do die. (A strong argument for perennials.)
Many perennials have disappeared in our gardens. They've moved their
act underground. They are very busy developing
roots and storing food since they don't have to feed the stems, flowers
and foliage. When they finally rest, their metabolism continues very slowly
and they are quite non-responsive to the environment around them.
You may have heard the old garden axiom, "Perennials sleep the first
year, they creep the second year, and they leap
the third year." This pattern is largely powered by the roots and their
winter activity.
-----
David Soper, The Garden Guy, writes and lectures on gardening topics. Read more on his website, Adventures in Gardening, www.gardenguy.com
