North Georgia Gardening Symposium, Feb. 26, 2015

The 2015 North Georgia Gardening Symposium is set for Thursday, February 26, at the North Metro Campus of Chattahoochee Technical College.

For landscape professionals, the Symposium provides for 5-hours pesticide re-certification credit for category 24 licenses or 1-hour pesticide re-certification for private applicators. It also has been approved for 5-hours (CEUs) for ISA Arborist and Municipal Specialists.

For everyone who attends, the Symposium offers a great opportunity to enhance garden and landscape knowledge and skills!

This year's offerings will help gardeners and landscapers avoid common mistakes in using broad-leaf herbicides, learn to diagnose common tree disorders in the landscape, and use the best and most innovative sustainable practices in landscape maintenance, and more.

8-8:30 a.m.                    Registration/Check-in 
8:30-9:30 a.m.               Herbicide Effects on Landscape Trees and Shrubs, by Paul Pugliese, Bartow County Extension
9:30 a.m.-10:30 a.m.      Creating Tough Turf, by Becky Griffin, UGA Extension Urban Ag Associate
10:30-10:45 a.m.            Break
10:45-11:45 a.m.           Tree Scene Investigation, Mary Carol Sheffield, Paulding County Extension
11:45 a.m. to 1:15 p.m.   Break for lunch and vendor visits 
1:15-2:15 p.m.                New Diseases, New Products, What Else is New?, by Dr. Jean Williams-Woodward, UGA Extension Plant Pathologist
2:15-3:15 p.m.               Sustainable Landscape Practices, by Dr. Bodie Pennisi, Extension Landscape Specialist
3:15-3:30 p.m.                Break
3:45-4:15 p.m.                The Latest and Greatest Plant Introductions, by Rex Bishop, Chattahoochee Technical College
4:15-4:30 p.m.                Pesticide re-certification/evaluation

The course fee is $35; lunch and breaks are included in the fee.

To register online, scroll down the list of courses for Continuing Professional Education to choose the North Georgia Gardening Symposium class and register. Also, you may call 770-528-4550 for more information or to register for the Symposium.

Azalea Leaves Turning Yellow, Dropping?

Evergreen Azalea in early December.  PHOTO/Amy W.

When leaves of a favorite, beautiful azalea turn yellow and begin to drop, a homeowner might become somewhat alarmed. We tend to think of azaleas as being evergreen, and in our minds, "evergreen" is nearly the same as "never-yellow."

However, the UGA publication Selecting and Growing Azaleas, by Extension specialists Wade, Braman, and Woodward, in cooperation with members of the Azalea Society of America, points out that not all azaleas are evergreen, and for those varieties, total leaf-drop is completely normal.

It turns out that some leaf yellowing and loss is completely normal for evergreen azaleas, too.

In the online article Are Your Evergreen Azalea Leaves Turning Yellow or Reddish-Purple This Fall?, Joey Williamson, of Clemson's Home and Garden Information Center, explains:

"Remember that no leaf lasts forever. The older leaves, further down the stems, will fall off during the late fall and early winter season..." He adds, "White and pale-pink colored azaleas will typically have bright yellow-colored foliage just before leaf drop."

For information about selecting, planting, and care of azaleas in the landscape, along with descriptions of other potential causes of leaf yellowing and lack of vigor in azaleas, read the UGA publication linked above.

For azaleas about which the cause of a problem is unclear, the local Extension office can be contacted to provide assistance in tracking down the cause.

Cobb Master Gardeners "Best of Atlanta"

The Through the Garden Gate 2014 garden tour of Cobb Extension's Master Gardeners has been chosen as a "Best of Atlanta" winner for 2014 by Atlanta Magazine. The recognition of the spectacular work of this service-oriented group of gardeners is well-deserved!

The annual garden tour and associated plant sale is the primary fundraising activity for the Master Gardener Volunteers of Cobb County (MGVOCC). The funds are used to support Master Gardener projects throughout the county, including school gardens, gardens that produce food for donation to local pantries, community gardens, historic gardens, and demonstration gardens.

The tour is of yards and gardens of our Master Gardeners, and they demonstrate what is possible in many kinds of yards. Docents (Master Gardeners!) are on site at the tour gardens to answer yard and garden questions.

The tour is held each year on the Saturday of Mother's Day weekend. For 2015, that date will be May 9. For additional information about the tour, please see the Garden Tour page of the MGVOCC.

Opportunities for Productive Activity in the Yard Continue

After the pansies are planted, weeds banished from the lawn, old mulch raked away from under the ornamental shrubs and fresh mulch spread in its place, what is left for the outdoor-work-loving homeowner to do? It turns out that there are plenty of excuses to be outside on beautiful winter days ahead!

The UGA Extension publication "Fall Gardening: A Collection of Information and Resources" includes some activities that should already have been completed back in September and October, such as planting fall vegetable crops and treating fire ant mounds, but it also includes activities for November and December.

These later-season activities include managing fallen leaves, improving vegetable garden soil, and taking care of the tools you rely on all the rest of the year.

Managing Fallen Leaves

County Extension Agent Paul Pugliese suggests rounding up all those leaves and, instead of bagging them to be  placed on the curb for hauling away, processing them to make mulch for your gardens. He says, "Large, whole leaves tend to get blown around and don’t stay within their landscape bed boundaries. The key to successfully using leaves for mulch is to shred them with a lawn mower, bagging attachment or leaf shredder so that they won’t blow away."

Newly planted trees and shrubs (planting is another great activity for the winter!) will benefit from having this shredded leaf mulch spread in a "donut" shape around their bases. Pugliese explains: "Mulch will help roots of newly planted trees and shrubs acclimate to the cold faster while they are becoming established this winter."

Improving Vegetable Garden Soil

Extension Vegetable Specialist Bob Westerfield says that, when he first started gardening, he used to just let his garden soil "lay idle throughout the fall and winter. I now know that is about the worst thing a gardener can do."

He says that leaving residues of old crops in the garden can provide a safe harbor for pests and diseases, so removing those is an essential task for gardeners who are hoping for successful crops next year. In addition, Westerfield says that this is the time to really pay attention to the soil and take additional steps that can help build the soil and decimate pests.

These are some steps Westerfield takes to improve his garden soil:

"If it isn’t too wet, I till the garden to expose any insects, nematodes and soil pathogens to the cool, dry weather. This is a perfect time to add amendments such as compost or other organic matter like manures. Sometimes I spread fallen tree leaves over the garden and till them in. They break down quickly into rich organic matter. Shred the leaves first under the lawn mower or in a chipper and they will break down even faster."

Protecting Your Tools

UGA News Editor Sharon Dowdy's section about taking care of tools pulls together suggestions from  Extension Specialists Bob Westerfield and Tony Johnson. Westerfield and Johnson agree that taking care of tools is important, partly because tools can be expensive to replace, and partly because a good once-over now can reduce unpleasant surprises in spring, of finding broken handles, dulled edges, or rust damage.

Here is part of the checklist they've provided:

Tiller and Mower

• Empty the garden tiller of fuel or add a fuel stabilizer.
• Check the spark plugs, change the oil and clean the air filter.
• Clean the underside of the mower’s deck with a pressure washer and scrape off any old grass and debris.

Shovels, Hoes and Other Tools

• Thoroughly clean all tools with soap and water.
• Sharpen blades.
• Clean metal parts with steel wool, wipe dry and apply a light coat of household oil.
• To save time in the spring, sharpen tool edges.
• Smooth wooden handles by sanding them with sand paper. Then coat handles in linseed oil or paint them to preserve the wood.
• Store all rakes with the teeth pointing down. Stepping on an exposed rake can be dangerous for children and adults.

Dowdy's section of the "Fall Gardening" publication also includes Westerfield and Johnson's maintenance suggestions for irrigation systems, tomato cages, and sprayers.

For the complete checklist, and for complete sections about fallen leaves and vegetable garden care, see the Fall Gardening publication.

New e-Newsletter for Cobb Extension Horticulture

Looking for timely tips and a longer view of the schedule of classes for Cobb Extension? This information can be delivered to your email inbox through a new e-Newsletter.

Each issue of the e-newsletter, the "Cobb Extension Horticulture News," will list Cobb Extension's public events and classes for the upcoming two months, tips for the care of lawns, gardens, and landscapes, and one or two timely, short articles.

A signup form for the emailed "Cobb Extension Horticulture News" is in the right-hand sidebar of this blog. The inaugural (i.e.: "guinea pig") issue will be released in early December, and subsequent issues will be delivered to subscriber in-boxes every two months through the year, beginning with a January/February issue.

We are looking forward to sharing up-to-date, research-based information about care of lawns, gardens, and landscapes and our natural resources through the newsletter!

Upcoming Events

Glitter and Greenery

Thursday, November 6, 6:30-8:00 p.m.  Learn how to take care of your holiday plants and trees, how to make wonderful herb flavored vinegars for gift giving, and much more. Presented by Horticulture Agent Neil Tarver and Family and Consumer Sciences agent Cindee Sweda at UGA Extension/Cobb County, second floor classroom, 678 South Cobb Drive, Marietta, GA, 30060. Free and open to the public, but preregistration is requested. Call 770-528-4070.

Holiday Inspirations

Saturday, November 8, 10:00 a.m. – 1:00 p.m. Cobb Extension staff will demonstrate easy holiday crafts and decorating ideas. Presented at UGA Extension/Cobb County, second floor classroom, 678 South Cobb Drive, Marietta, GA, 30060. Free and open to the public, but preregistration is requested. Call 770-528-4070.

Adaptive Gardening – How to Keep Gardening on Your Lifetime Can-Do List

Tuesday, November 11, 7:00-8:00 p.m. Presented by Master Gardener Joe Washington as part of the ongoing Gardeners Night Out presentation series of the Master Gardener Volunteers of Cobb County, at Mountain View Regional Library, 3320 Sandy Plains Road, Marietta, GA, 30066. Free and open to the public.

Bonsai

Friday, November 14, noon-1:00 p.m. Michael Stoddard, Board of Directors, Atlanta Bonsai Society, will bring his bonsai to show us how to plant, prune, and care for our own, as part of the ongoing Lunch & Learn series of the Master Gardener Volunteers of Cobb County, at the Training Room of the Cobb County Water lab, 662 South Cobb Drive (at the intersection with Atlanta Rd.).

Thyme to Read Book Club

Friday, November 14, 10:15 -11:30 a.m. Book club sponsored by Cobb County Master Gardeners will meet at the Training Room of the Cobb County Water lab, 662 South Cobb Drive (at the intersection with Atlanta Rd.). This month’s book is The Founding Gardeners, by Andrea Wulf. Schedule and information can be found at www.cobbmastergardeners.com. Free and open to the public.

Bluebird Trail Tour

Saturday, November 22, 10:00 a.m. to noon, and again on Saturday December 6, 10:00 a.m. to noon. Free and open to the public. Cobb Master Gardener and Bluebird expert Jim Bearden will conduct a guided walk of the 2.3-mile Bluebird Trail at Green Meadow Preserve Park, at 3780 Dallas Hwy., Powder Springs, GA, 30127. Follow the Bluebird Trail blog at bluebirdtrail.blogspot.com.

Planning for Color with Spring-Flowering Bulbs

Neighborhoods across Cobb County are awash in the reds and yellows of autumn leaves, and  the cool-season blooms of asters, mums, pansies, snapdragons, and more are keeping our landscapes lively, but we all know that winter will be upon us soon, and much of the color will fade. Forward-thinking gardeners, however, prepare for the early return of blooms with spring bulbs.

It isn't quite time to start planting most spring-flowering bulbs in Cobb County -- November is our best month -- but it isn't too soon to start selecting the bulbs and planning where to place them.

For gardeners who may be new to our area, the UGA Extension publication "Flowering bulbs for Georgia gardens," by Paul Thomas, Gary Wade, and Bodie Pennisi, describes the many flowering bulbs that can be grown successfully in our area. In addition to the familiar and hardy daffodils and crocus, gardeners here can select Spanish bluebells, glory-of-the-snow (which is glorious even without snow), hyacinth, star flower, rain lilies, and more.

The 2012 Georgia FACES article "Plant flowering bulbs now for color later," by UGA's William Tyson, emphasizes the importance of selecting high-quality bulbs that are large for their type and that are unblemished.

For planting, Tyson explains, "Most prefer a moist, well-drained, medium, sandy loam that does not remain wet and sticky after heavy rain or dry out too quickly. Good drainage is essential."

For spacing and depth, Tyson includes these details:

"A general rule of thumb for planting depth (from the top of the bulb to the soil surface) is two to three times the greatest diameter for bulbs 2 inches or more in diameter, and three to four times the greatest diameter for smaller bulbs.

Spacing will vary from 1 or 2 inches to as much as several feet. When spacing bulbs, consider not only how much space each plant needs, but also how frequently it will be dug up and divided."

For fuller information, read the complete text at the linked titles above.

Curing Sweet Potatoes Enhances Sweetness and Storage-life

Home gardeners all over Cobb County will be digging up their sweet potatoes this month, if they haven't already. These gardeners probably know what UGA Extension specialists Malgorzata Florkowska and Robert Westerfield, in their publication "Home garden sweet potatoes," explain about sweet potatoes -- that they "...should be harvested before the first frost. Cool soil reduces their quality and storage life."

Newly harvested home garden sweet potatoes    PHOTO/Amy W.

However, soil temperature isn't the only factor that can affect the "quality and storage life" of sweet potatoes; correct post-harvest curing and storage can vastly improve the sugar content and keeping qualities of home garden sweet potatoes.

Clemson University's Extension Sweet potato publication explains, "Sweet potatoes should be cured to heal wounds and to convert some of the starch in the roots to sugar. The optimal conditions for curing are to expose the roots to 85 °F and 90-percent humidity for one week. Few home gardeners can supply these conditions, so place the sweet potatoes in the warmest room in the house, usually the kitchen, for 14 days. No curing will occur at temperatures below 70 °F."

The online article "Growing sweet potatoes in the Sacramento area," by the Master Gardeners of Sacramento County, California, also notes that newly dug sweet potatoes are more starchy than sweet, and that the curing process that improves keeping quality also aids in the conversion of some of that starch into sugar.

For curing, these gardeners suggest using a slightly longer exposure of 10-14 days at 85 degrees F and 90% humidity. Most of us do not have access to the once-ubiquitous sweet potato curing barns (see this 2009 Master's Thesis -- Sweet Potato Curing Barns: An Agricultural Landmark) that were designed to provide these ideal conditions, but the Sacramento article includes ideas for how to create those conditions at home.

For storage after curing, the Sacramento Master Gardeners offer this additional information: "Once the roots are cured, they can then be stored in a dry, dark, well-ventilated place at 55° to 60°F for several months. Sweet potato roots are very sensitive to chilling injury at temperatures below 50°F, so do not store them at lower temperatures or quality will deteriorate. Symptoms of chilling injury include fungal decay, internal pulp browning, and root shriveling."

Upcoming Events and Classes

Thyme to Read Book Club (note updated, slightly earlier start-time)

Friday, October 10, 10:30-11:30 10:15 -11:30 a.m. Book club sponsored by Cobb County Master Gardeners will meet at the Training Room of the Cobb County Water lab, 662 South Cobb Drive (at the intersection with Atlanta Rd.). This month’s book is The Forgotten Garden, by Kate Morton. November’s book will be The Founding Gardeners, by Andrea Wulf. Schedule and information can be found at www.cobbmastergardeners.com.

Landscaping and Septic Tanks

Friday, October 10, noon-1:00 p.m. Presented by Cobb County Extension Horticulture Agent Neil Tarver, as part of the ongoing Lunch & Learn series of the Master Gardener Volunteers of Cobb County, at the Training Room of the Cobb County Water lab, 662 South Cobb Drive (at the intersection with Atlanta Rd.). Free and open to the public.

Trees of Our Lives: Small Native Trees for the Landscape

Tuesday, October 14, 7:00-8:00 p.m.  Presented by Dawn Hines, as part of the ongoing Gardeners Night Out presentation series of the Master Gardener Volunteers of Cobb County, at South Cobb Regional Library, 805 Clay Road, Mableton, 30126.

Moving Toward Organics in the Vegetable Garden

Saturday, October 18, 10:30 – 11:30 a.m. Free and open to the public. Learn what organic gardening and farming really means and steps you can take to have a more environmentally friendly garden.  Presented by Cooperative Extension horticulture staff member Amy Whitney at the community garden at Chestnut Ridge Christian Church, 2663 Johnson Ferry Rd, Marietta, GA, 30062.

Gifts from the Kitchen

Tuesday, October 28, 6:00-8:30 p.m. Learn to use a water bath canner to make holiday gifts from your kitchen. Taught by Family and Consumer Sciences Agent Cindee Sweda at UGA Extension/Cobb County, second floor, 678 South Cobb Drive, Marietta, GA, 30060. $10 fee; preregistration required before Oct. 17; space is limited. For additional information and to preregister, call 770-528-4070.

Pansies for Winter Color

Even as the summer growing season winds down, homeowners are thinking about ways to add flowers to the winter landscape. Happily, garden centers currently are overflowing with flats of pansies, and those can make great additions to a yard.

UGA's Success with Pansies in the Winter Landscape, by Extension Horticulturists Gary Wade and Paul Thomas, includes helpful information for home-plantings of pansies, even though it was written for landscape professionals. In addition to a map that shows best planting dates for all of Georgia, details of how to amend the soil, plant, mulch, and care for the pansies through the winter are all explained.

For Cobb County, the first two weeks in October are shown to be optimum for planting pansies. For planting, the publication describes the procedure outlined here:

1. Raise the planting bed above-grade to help create well-drained soil - "pansies cannot tolerate wet feet."
2. Rake away any old mulch and remove and discard old vegetation.
3. Amend the soil with fully decomposed organic materials, but not too much (less than 25%).
4. Check soil pH and adjust to a range between 5.4 and 5.8.
5. Fertilize, but "Avoid using fertilizer containing high amounts of slow-release ammoniacal nitrogen."
6. Plant at 6, 8, or 10-inch spacing.
7. Mulch the soil surface.
8. Water! "A thorough watering immediately after planting will help eliminate air pockets around plant roots."

For fuller information about the above steps and about after-planting care of the pansy bed, read the article linked through the article title.

rs containinghigh amounts of slow-release ammoniacal nitrogen.

Manage Spring Dead Spot with Fungicide Application Now

Did your Bermudagrass lawn suffer from spring dead spot disease this year? The UGA Extension publication "Identification and Control of Spring Dead Spot", by Extension specialists Alfredo Martinez, J.B. Workman, and F. C. Waltz, explains that the disease is especially prevalent after a hard winter, such as the one we experienced last year. This means that any Bermudagrass lawn affected this past growing season had plenty of company.

Even though it may seem counter-intuitive, chemical controls for spring dead spot (SDS) should be applied in fall, when soil temperatures are still above 60 degrees F, according to Martinez et al. This application can help prevent re-emergence of the disease next year.

SDS first shows up in late spring. The publication says this about signs of infection: "As turfgrass 'greens up,' well-defined circular patches of dead, bleached-out grass are noticeable in affected areas. Non-infected bermudagrass resumes growth, accentuating the infected areas."

The authors add, "Patches can get larger year after year." To avoid this outcome, altering cultural practices to promote good health of the lawn is important. One practice in particular is to avoid  applying more than a half-pound of nitrogen fertilizer per thousand square feet after mid-September; another is to consider applying a potassium fertilizer, at the rate of one pound potassium per thousand square feet, in fall.

The Turf section of the Georgia Pest Management Handbook, homeowner edition, by Extension homeowner IPM specialist Elizabeth Little, agrees with these recommendations, and includes a listing of currently recommended products for controlling SDS. Regardless of the product selected from the list, be sure to follow label recommendations and safety precautions.

The Turf section of the handbook linked above, which also contains information about insect and weed control in lawns, lists specific cultural practices that can help to manage SDS:

• "Avoid late summer or fall applications of nitrogen fertilizers which may enhance disease severity.
• Use ammonium sources of nitrogen fertilizer from spring through early August.
• Control weeds in affected turf to enhance recovery from spring dead spot.
• Apply moderate to high levels of phosphorus, potash, and minor elements.
• Improve drainage of turf.
• Reduce thatch.
• Use preventive fungicide applications in late September and October."

Upcoming Events

Fall Landscaping Activities

Tuesday, September 16, 6:30-8:00 p.m. Presented by Cobb County Extension Horticulture Agent Neil Tarver, at UGA Extension/Cobb County, second floor, 678 South Cobb Drive, Marietta, GA, 30060. Free and open to the public, but please preregister by calling 770-528-4070.

Indoor Plants

Thursday, September 18, 10:30 a.m. to Noon. Presented by Cobb Extension horticulture staff member Amy Whitney, at UGA Extension/Cobb County, second floor, 678 South Cobb Drive, Marietta, GA, 30060. Free and open to the public, but please preregister by calling 770-528-4070.

Green Industry Update

Tuesday, September 30, 8:30 a.m. (registration until 9 a.m.) to noon. Recertification credits: 21/23/24/27 = 3 hours; ISA = 2.5 hours; Private = 1 hours. $10 per person at the door; Pre-register with cornelius.tarver@cobbcounty.org or by calling 770-528-4070. Reduce pest problems with proper tree selection and planting, Joe Burgess, Georgia Forestry Commission; Control spring turf diseases with fall fungicide applications, Neil Tarver, UGA Extension in Cobb County; Interpreting pesticide labels is key to pesticide safety, Milton (Micky) Taylor, UGA Dept. of Entomology.

Bluebird Trail Tour

Saturday, October 4, 10:00 a.m. –Noon. Free and open to the public. Cobb Master Gardener and Bluebird expert Jim Bearden will conduct a guided walk of the 2.3-mile Bluebird Trail at Green Meadow Preserve Park, at 3780 Dallas Hwy., Powder Springs, GA, 30127. Follow the Bluebird Trail blog at bluebirdtrail.blogspot.com.

Thyme to Read Book Club

Friday, October 10, 10:30 -11:30 a.m. Book club sponsored by Cobb County Master Gardeners will meet at the Training Room of the Cobb County Water lab, 662 South Cobb Drive (at the intersection with Atlanta Rd.). This month’s book is The Forgotten Garden, by Kate Morton. November’s book will be The Founding Gardeners, by Andrea Wulf. Schedule and information can be found at www.cobbmastergardeners.com. Free and open to the public.

Landscaping and Septic Tanks

Friday, October 10, noon-1:00 p.m. Presented by Cobb County Extension Horticulture Agent Neil Tarver, as part of the ongoing Lunch & Learn series of the Master Gardener Volunteers of Cobb County, at the Training Room of the Cobb County Water lab, 662 South Cobb Drive (at the intersection with Atlanta Rd.).

Trees of Our Lives: Small Native Trees for the Landscape

Tuesday, October 14, 7:00-8:00 p.m.  Presented by Master Gardener Dawn Hines, as part of the ongoing Gardeners Night Out presentation series of the Master Gardener Volunteers of Cobb County, at South Cobb Regional Library, 805 Clay Road, Mableton, 30126.