Time for Mums- chrysanthemums that is…
Some of
the plants we call mums have been analyzed and found wanting, that
is, they have been transferred to another genus. We can live with
those decisions; we love them under any name. While summer’s annuals
and perennials are showing their age, the Chrysanthemums are just
now in full flower. Autumn flowers such as mums, poinsettias, and
asters sense the changes in day length: it is as if they notice the
days shortening so realize if they want to put on a display before
frost, they’d best get a move on.
We know plants bloom according to day length but they
also open and close at specific times of the day. Carolus Linnaeus,
the 18th Century Swedish naturalist designed a floral
clock in which the time could be ‘read’ by the opening and closing
of the blooms. By close observation Linnaeus had determined those
times for several species. For example, marigold, Tagetes erecta,
opens at 7 AM and closes at 3 in the afternoon. His notations are
probably not relevant to our lower latitudes and evolved species,
but such a clock would surely be a waltz of the flowers.
If you were born between 23 October and 21 November
Chrysanthemums are said to be your lucky flower. Actually they are
lucky for all gardeners. The tough old-time perennials are not like
the mounds of blooms offered for sale during the fall season. These
decorative pots should be treated as a one-time display as they do
not always winter over. The older sorts put forth their distinctive
foliage in March sprouting from stolons creeping away from the
mother plant. March is the time to divide them. If they tend to
sprawl they can be trimmed back in early July.
We have been advised to keep a lookout for signs of
Chrysanthemum White rust, caused by the fungus Puccinia horiana.
This rust was discovered at a Fairfax County retail nursery on
September 24, 2009 by a Department of Agriculture and Consumer
Services (VDACS) inspector. The plants showing signs of the fungus
had been imported from other states. Eradication protocols were
followed hoping to prevent spread of the disease. Originating in
eastern Asia this rust has spread to Europe, Africa, Australia,
Central and South America. Cool wet weather favors its spread and it
affects chrysanthemum, dendranthemum, nipponanthemum, and
leucanthemum species.
Good News: We have been so fortunate in the rain this past
summer. I read that more than 50% of all water use in cities, towns
and villages goes onto our outside lawns and shrubs. Some irrigation
experts say that we dump between 30% and 300% more water on our
landscape than is actually required. You probably already know this
having watched automatic sprinkler systems whirling away in the
rain! Or you have watched sprinkled water rush away down the drive
to the ditch. When 2/3 of the country faces increasingly threatened
supplies of water, such misuse is garden variety dumb. However,
there is a company now making a device with the potential to add a
brain to the 60 million automatic watering systems in this country.
It will save money and water by computing weather, sun, shade, and
soil. You knew someone would invent that, didn’t you?
Bad News: Along the
Brittany coast of Northern France sea lettuce, Ulva lactuca has
caused the death of a horse and a truck driver. This seaweed is
harmless in the water but when drying on the beach it emits a toxic
gas. The horse collapsed and died as it was being ridden over the
sands. The rider was unconscious but was rescued.
The truck driver
was hauling the seaweed off the beach without a mask or gloves. His
job was part of an effort to remove 2000 tons of the the drying
seaweed off the beaches. The explosion of algae is due to the high
levels of nitrogen used in fertilizer as well as the nitrogen
excreted by the region’s high concentration of livestock.
Good News: A major
strategy for mitigating climate change is a shift from annual to
perennial grains, a technique that lowers the CO2 emissions
resulting from annual plowing and fertilizer use. In Washington
State some perennial wheat varieties have been developed and the
test yield had been more than 70% of the conventional annual wheat
yield – not bad for a beginning effort.