By Kathy Conner Cornell
Southside Master Gardener
Have
you ever really thought about how do plants know when to start budding and
leafing out? There isn’t a calendar that
tells them, ok its time. This is just
one fascinating aspect of plants. They
do things we do to survive – make their own food, feed the entire plant,
procreate, breathe – all in one spot.
The common lilac is my favorite spring blooming shrub. Without a cold winter, flower buds will not set.
As you would expect, temperature is part of the
equation. Plants need to be adaptable to
maintain dormancy when we get 70 degree days in February. Because weather is more variable on the East
Coast than it is in Europe and Asia, native plants are better at not leafing
out during those early bursts of temperatures.
Don’t tell that to the daffodils.
As soon as the weather warms for a couple of days, the daffodils start
to sprout out. I’ve got some blooming in
my yard right now. Surprisingly, they
seem to be able to bounce back when the temps drop like they have this week.
Since lilacs are early bloomers, they already have leaves
sprouting out. The plant can withstand
some cold temps without causing harm. Not so with fruit trees. It seems our peaches just want to get going
early so they have already budded out.
These cold nights are going to destroy those buds, so no peaches this
year.
Another aspect is day length. Plants can sense the days getting
longer. They certainly don’t know
whether it is Eastern Standard Time or Daylight Saving Time. The day length is the same either way. Day length coupled with consistently warm
temperatures is a good trigger for safe spring growth to start.
Something a lot of people don’t want to accept, is climate
change. In the past, we expected
forsythia to bloom in April. They are in
full bloom now in mid-March. If you feel
that the stuffy nose and watery eyes associated with pollen allergies are
happening sooner, you are right. Because
temps are warming ahead of the time they did in the past, plants are producing
pollen earlier and causing the allergy producing event to last longer. Higher amounts of carbon dioxide in the air
also contributes to the rising temp cycle and plants wanting to get going.
We can’t control how a plant reacts to the weather. We can only sit back and relax and enjoy the
glory of things blooming and greening up.
Come on Spring!
