Thursday, September 27, 2012

Impatiens blight disease -- Trouble in the landscape

impatiens blight disease 2013
Impatiens blight disease will likely continue in 2017
Downy mildew has arrived in the Mitten.  Impatiens blight disease.  Don't be fooled by the soft moniker--this ornamental flower killer means business.  "It is likely that impatiens could lose their place in our landscapes if they cannot be grown reliably."  This quote from the esteemed Michigan State Extension Service causes icy fingers to clamp around the heart of gardeners who've relied for decades on these colorful and easy plants to provide tone  and warmth to the shade garden. 

impatiens fungus 2013
Impatiens fungus or blight hit hard in 2012 and is full blown in 2013.  First the plants appeared sickly.  Then the blooms fell off, leaving translucent stems pointed upward like outstretched fingers from an open hand.  Those disappeared, leaving only a puzzled memory of last year's hearty fall blooms.  Chalking it up to a chilly spring followed by the hottest July in recorded US history, there was only passing concern.  When the stalwarts in the windowbox began to fade the circumstances became troublesome.  All those lovely flats painstakingly planted-- for naught.  Will this happen again?

At a Sunday baby shower hushed whispers about an "airborne" disease triggered alarm.  Is this blight insidious or an aberation?  Are there measures to prevent the future spread of disease for next season?

Look for pale white spots on the underside of leaves.  Remove the leaves and destroy.  There are commercial fungicides available from growers.  Copper based fungicides would be more attractive to naturalists.  Once a plant is infected, it's too late for the fungicide.  Organic gardeners should rely on prevention and early intervention:
  1.  Lift the leaves before you buy.  The disease begins at the greenhouse.
  2. Avoid overhead watering, irrigate the plants with watering cans or hoses directed at the base.
  3. Chose a site with good drainage, medium early sun access and low humidity.
  4. Use adequate but not excessive fertility.
  5. Monitor the plants frequently, removing diseases leaves.
  6. Clean tools frequently.
  7. Remove infected plants and try to avoid spreading by touch.
Impatiens are officially off the "low maintenance" list.  At least they weren't a cash crop. 

A safe bet?  New Guinea impatiens are resistant to downy mildew. 

A new introduction, Sunpatiens are designed to thrive in sunny areas and seem exempt from the disease.  These planted in a warm front bed amongst lavender and cleome were slow to take, but have bloomed heartily in September. 

But will so miss those bloomin' bizzy lizzies!

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Monday, September 24, 2012

Turtlehead and other Fall Blooming Flowers

Fall bloomers not only add pastel hues to the jewel tones of the fall yard, they complement the shade garden. Holding back the show until autumn, these subtle blooms are well worth the wait.   

Left to seed, autumn arrivals give impact to the winter garden--robust blooms nabbing snowflakes for interest

Turtlehead a/k/a chelone
Sturdy turtlehead is slow to establish, but a reliable perennial that thrives in the shade garden--adding structure and height through September when lipstick pink blooms arrive.  Low maintenance, disease and fungi resistant, these uncommon plants are worth the search. A batch at the base of the driveway always draws comments from passersby and the hardy gals thrive despite the giant oak that interrupts the sweeping spray of the sprinkler system.

Reliable hosta sprouts elongated blooms of frilly purple or white.

Shrubs do the heavy lifting as burning bush and hydrangea reach their peak of color.

Black cohosh, a native plant, sets out white blossoms resembling giant caterpillars.  These blooms droop gently or wave gaily in the chilly breeze. 

Reliable sedum sets out honeycombed blooms of pink, red and burgundy.  Left on the stem through winter, they deepen giving contrast to the white winterscape.  Red flag grass throws out plum colored tassels which capture the wind. 

Fall blooming plants tend not to be delicate. To survive the heat of summer then gracefully transition to the vagrancies of cool fall requires some strength of character and color n'est pas?

It's not all burgundy and bronzes in the October garden, as dramatic monkshood give the yard  a regal blue hue before winter sets in...

Frost on the pumpkin!


Friday, September 14, 2012

Yellow Flowers -- Blooming Sunshine

Reflective, structural, colorful, complementary-- yellow flowers provide it all. From the moment each tiny daffodil first casts its glow over the dull winter landscape, to the last golden maple leaf drifitng downward towards winter's cold arrival--golden tones anchor the happy garden.

Colors undeniably touch our souls.  Red invokes passionate thoughts of love or anger (or both.)  Blue reflects the sky and encourages calmness and serenity. 
Yellow provides the highest impact, with the least effort.  Golden plants are notoriously low maintenance.  Sturdy members of the plant community, there's always a need and a place for these mirrors of sunshine.
Daffodil bulbs can be planted en masse or in tiny pockets of surprise.  Their fading foliage can be easily cut back or allowed to disappear beneath late spring arrivals.  Squirrel permitting, Daffodils will reappear for many years with no need for nutritional or liquid supplement. Plant a few extras in a hidden location to clip for the kitchen or hall table.  
Soon after, sunny forsythia brightens up everything from freeways to grocery lots.   

Later, throughout the warm months, waves of gold replicate in masses of liriope, cut flower and yarrow.

Golden hosta lighten up shaded spots.

Late summer's when the luminous show hits its peak.  Deep yellow petals framing blackened centers announce the arrival of hardy Black Eyed Susans.  These long blooming mainstays require little maintenance and last through fall.  Planted in a sunny location, they will thrive, needed only cutting back in late fall, after the dried blooms have turned a dusky fallish brown. Even in partial sun, the show's not as elaborate, but still plant-worthy. Leave Susan in for winter interest.  Sturdy stems stand up to early snowfall.  Susans are easily divided and transplanted.  By the second season following movement, the plants are well established.

Yellow plants may not be exotic, scarce  nor uncommon, but they're the backbone of a busy garden.  Shying away from the common golden Stella D'Oro after seeing it in practically every commercial planting, I relented and included bunches in the yard, dotting the main approach.  Stella's still there, as reliable and colorful as ever, most years blooming in both late spring and early fall. 

The assertive tone may imply the need to grab the limelight, but the true value of golden plants is the contrast provided to deeper hues of purple, violet and blues.  Planted next to blue salvia, lavender, or hot pink phlox, yellow blooms accentuate their purple hued counterparts to perfection.  Neither outshines the other.

Blooming sunshine.  Points of light. Warmth, brightness and essential for any garden. 

Yellow thrives in the wild.  Atop a dry summer mountain, the only color is gold.

Truly, there's always a place for sunshine. 

Even on a cloudy day. 
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