A New Script for Rebloom
By Mike Lockatell, AIS Region 4 Reblooming Iris Chairman

Click HERE for the full text of the article (pdf)

American Iris Society Region 4—The Newscast August 2012 p. 10-11

Good Culture Ensures Rebloom--From Iris Austin, June 2012

Read the full text HERE

Reblooming Bearded Irises

Reblooming Bearded Irises have existed for decades.  Unlike “Encore®” Reblooming Azaleas, these special perennial plants received minimal attention from Iris fanciers.  Public notice finally arrived in the late nineties due to a feature story appearing in Martha Steward Living Magazine.  Product demand forced major producers to list selections in their yearly catalogs.

Spring only flowering bearded irises cannot become a reblooming one.  Remontants (rebloomers) are bred for spring and fall flowering.  As hybridizers such as the late Dr. Lloyd Zurbrigg formerly of Radford, VA and Durham, NC retired, concrete performance data and new development saw a significant decline over the past decade.  Since rebloom origins are difficult to pinpoint, only a handful of dedicated breeders across the US and Canada are actively working for new color breaks and patterns plus better fall reliability.  One current goal is to move the fall bloom sequence up to late August or early September.  Such progress would allow gardeners in colder climates the chance to enjoy these marvelous heirloom plants in fall flower.

Gardeners should use extreme caution in ordering plants from mail order catalogs and print media ads.  Growers fail to make the distinction between warm and cool season varieties.  West Coast selections may not grow or flower in fickle Mid-Atlantic growing conditions.  Consult reputable local growers for the best choices in performance and fall bloom reliability.

Mike Lockatell                                            

Roots & Blooms, LLC                                   

The Joyce Lockatell Memorial Garden

500 Pantela Drive

North Chesterfield, VA 23235

(804) 330-2916

CMarti8855@verizon.net

rootsandblooms.us

The Great Clarence Mystery

Mike has published an article proposing a solution to the "Great Clarence Mystery"--the unknown parentage of one of the most breathtaking of Lloyd Zurbrigg's reblooming irises. "Clarence" was a finalist for the prestigious Dykes Medal, but failed to win it due to uncertain antecedents.

The article was published in "Irises: The Bulletin of the American Iris Society" vol 92(2), April 2011, and appears HERE by permission.

Rebloom Seeks Good Fortune (Published in American Iris Society Region 4 Newscast, March 2012)

Mike's article linked here recently appeared in the March 2012 issue of The Newscast,  the newsletter of Region 4 of the American Iris Society.

Winter Weeds on the Attack

A mild winter is a mixed bag.  Homeowners have hopefully enjoyed lower heating bills.  Landscape contractors and arborists continue to work without the threat of freezing temperatures in an effort to get a jump start on the upcoming spring season. 

Since the groundhog in PA made his annual declaration in early February, winter daytime temperatures remain above normal.  Winter weeds such as chickweed, henbit, Bittercress and dandelions have been on a rampage in plantings beds and lawns.  Bittercress continues to make new appearances in the suburban landscape.  Like its fellow noxious broadleaf weeds, gardeners should not ignore its existence in the yard. 

Hairy Bittercress (Cardamine hirsuta) germinates and grows into a basil rosette with small dark segmented foliage.  It has a mounded appearance composed of pinnate leaves with alternate 1-2-3 parts of round to kidney shapes leaflets.  Petioles are prominent and hairy.  Flower stems are erect and smooth sporting little foliage.

Small (2-3mm in diameter) white blooms have four tiny petals.  They are arranged in dense racemes.  (The floral structure is on a smaller scale similar to hyacinth flowers.)  Long and narrow purple seed heads can measure up to l.5 cm to 2 cm in length.  Its fruit are known as “Siliques” and can explosively spread seed as much as 10 feet from the parent plant.  Any contact such as walking, raking, weeding, lawn mowing activates seed dispersal. 

Heavy hairy Bittercress infestations are mainly evident in early spring.  Home gardeners can easily forget about this broadleaf weed’s presence around the landscape during the remainder of the growing season. Control measures require timely post emergent herbicide applications in spring and fall.  This weed’s unique and efficient seed distribution mechanism can NOT be underestimated.  If Bittercress infestations are manageable, mechanical removal is highly recommended before and during flowering.  The same advice is helpful for henbit, chickweed and annual bluegrass control. 

Avid home gardeners are strongly advised to contact your local Cooperative Extension Office to discuss the latest recommendations to curb this aggressive broadleaf weed.  Be vigilant now to avoid later pain. 

Peony Care Starts in Early Spring

Herbaceous peonies are rugged heirloom perennial plants valued for their drought tolerance and deer resistance.  Breeders continue to introduce exciting hybrids to the marketplace featuring new color breaks, patterns and flower forms though carefully selected, nature will find any defect.

Hybrid herbaceous peonies flourish in mild springs.  Flower durability and longevity translates into a long bloom season.  Wet springs punctuated by persistent rainfall are a perfect environment for disease outbreaks. A chemical program begun in early spring as new shoots emerge mitigates future fungal problems. 

Powdery Mildew

Botrytis blight (Botrytis paeoniae), measles (Cladosporium paeoniae), and powdery mildew (Erisyphe polygoni) fungal spores can easily jump from plant to plant.  Heavy winds or rains are great transportation modes for these nasty pathogens.  Infection from neighborhood plantings or new garden center purchases is entirely possible.  Rather than lamenting over misfortune or exacting blame, know the facts and respond with proper identification and treatment. 

Botrytis is the most common peony disease.  Symptoms appear in late spring on young leaf shoots about one foot in height.  Susceptible center stems wilt and die.  A brown or blackish rot appears at the base of leaves and stems.  Affected areas of the stalk above ground will be covered by a gray mold filled with large spore populations.  Immediate removal and treatment is essential to combat infection.

Peony Measles or “Red Spot” resemble small circular discolored lesions on leaves.  Spots can combine to make foliate look irregularly blotched.  The under surface of these areas becomes light brown.  Different powdery mildew disease species can attack plants in the home and commercial landscape.  Native dogwoods and hybrid lilac, honeysuckle, bee balm and zinnias are common hosts for these fungi.  Herbaceous peonies have their own powdery mildew specialists that develop as a white film on leaves and stems.  Infestation effects are seen in late summer.  Protection applied during wet springs mitigates the disease’s devastating visual appearance.

Immunox® (Myclobutanil) is a reliable systemic fungicide labeled for botrytis and peony measles control.  Spectracide® packages formulations in one quart containers for tank mixing.  The Pest Management Guide from Virginia Cooperative Extension also suggests Ortho® Rosepride® (triforine) for powdery mildew control.  Protective sprays should be made during favorable disease conditions as new foliage emerges and matures through spring.  A spray for Measles is a good tool immediately following bloom season. 



Remove Old Blooms

 Good garden sanitation is a must.  Spent flowers should be immediately removed during bloom season.  Remove declining foliage each October.  Collected debris should be tossed in the garbage or burned.  NO COMPOSTING.  Additional advice and information can be obtained from your local Cooperative Extension Office.  Please follow product label for mixing and applying registered pesticides.  Use a spreader sticker (surfactant) in your spray solution for best results.