An incurable disease is wiping out the common impatiens |
A few years ago when I was in
England for a press day at David Austin English Roses, I met a delightful woman who
owned her own film company.
We became friends and before
long she asked me to work with her and write a couple of videos for the
Thompson & Morgan seed company.
The point of the videos was
to introduce the firm’s new offerings for the upcoming season. One of the biggest
stars of the T&M show was the Busy Lizzie, or as we call the plant, impatiens.
There were Busy Lizzies for
borders, flower pouches, patio pots and hanging baskets.
Today Thompson & Morgan
no longer sell the plants.
They don’t even sell the seeds.
That's because a deadly
strain of downy mildew known as Plasmopara obducens is destroying plants around the world.
A pathogen first discovered in the 1800's
A pathogen first discovered in the 1800's
The disastrous disease hit
Europe about five years ago. Since then, impatiens have virtually disappeared from
gardens there. Asia, Australia, Africa and Central America have suffered the
same fate.
In just two growing seasons
here in America, the fungal mildew has spread to 34 states. Under the right
conditions, airborne spores have been known to travel over 600 miles in 48
hours.
When infected leaves and
stems fall on the ground, the spores take up residence in the soil. No one
knows for sure how long the spores will live there – possibly as long as eight
years.
SunPatiens Compact Blush Pink |
I can attest to quick spread
of disease.
I had some “volunteers” come up in the front garden from impatiens
I planted in 2011. I also put in two flats of white impatiens down by the new
patio and waterfall.
By August the leaves started
falling and within two weeks they all turned to mush.
As a result of the widespread
nature of this incurable disease, many experts are advising gardeners not to
purchase and plant impatiens this year. Fortunately, only the common variety
(Impatiens walleriana) is affected by the pathogen.
SunPatiens and New Guinea Impatiens
are in the clear. Apparently the disease does not sicken other garden plants
either, so shade lovers like coleus, caladiums, hostas and begonias can help
add color in areas where impatiens previously were the summer show-offs.
SunPatiens Vigorous Lavender |
I am intrigued by photos I’ve
seen of SunPatiens. They can be planted in full sun as well as shade and they
grow much larger than the old favorite.
In fact Sakata Seed America,
breeder of SunPatiens, reports four plants will provide the same coverage as twelve
Impatiens walleriana.
In addition, they are self
cleaning, don’t mind rain, high heat or humidity. And they bloom right through from
spring till hard frost.
If you simply can’t live
without your beloved old fashioned Busy Lizzies and are willing to risk
Plasmopara obducens, you need to be diligent about garden sanitation.
Keep your tools super clean,
making sure you wash away any soil. To be extra careful, disinfect tools with a
solution of 10% Clorox and water.
Also schedule work in the
impatiens bed as your last gardening chore of the day.
SunPatiens Spreading White |
If the disease comes to call
anyway, place infected plants in sealed bags and dispose of them as soon as
possible.
As for me, I’ll give
impatiens a miss this year. Except I’m going to try a few of the new SunPatiens.
Last year’s experience was
too heartbreaking to go through again.