December 2016 / Volume 117
December Garden, Lawn, and Landscaping Tips


Keep all plants watered during dry conditions even though some may be dormant.   If precipitation has been deficient (1" of snow = ~ 1/10" of water), water lawns, trees, and shrubs, especially broad-leaf  and narrow-leaf  evergreens. Double check moisture in protected or raised planters.

Irrigate all plantings at least 24 hours before hard-freezing weather if soil is dry (HLA-6404).

Inspect your irrigation system and replace worn or broken parts.

Check on supplies of pesticides. Secure a copy of current recommendations and post them in a convenient place. Dilution and quantity tables are also useful.

Order gardening supplies for next season.  
Check that gardening tools and equipment are in good repair-sharpen, paint, and repair mowers, edgers, sprayers, and dusters.

Now is a great time to design and make structural improvements in your garden and landscape.

Send for mail-order catalogs if you are not already on their mailing lists.

Christmas gift ideas for the gardener might include tools, kneeling benches/seats, garden books and magazine subscriptions.

Clean and fill bird feeders.

Make sure indoor plants are receiving enough light, or set up an indoor fluorescent plant light.

Till garden plots without a cover crop to further expose garden pests to harsh winter conditions.

Visit your county extension office to obtain gardening fact sheets for the new gardening season.  The OSU Extension Office has plenty of fact sheets and help!

Join a horticulture, plant or urban forestry society and support community "greening" or "beautification" projects.

Review your garden records so you can correct past mistakes.  Purchase a new gardening journal or calendar to keep the New Year's gardening records.  NOTE: Master Gardeners will have free gardening journals available again in 2017.  You can pick one up at the HBA Home & Garden Show in early March.  
Fruits & Nuts

Cover strawberry plants with a mulch about 3 to 4 inches thick if plants are prone to winter injury.

Wait to prune fruit trees until late February or March.


Remove leaves from cool-season grasses or mow with a mulching mower (HLA-6420).

Continue to control broadleaf weeds in well-established warm-season or cool-season lawns with a post-emergent broadleaf weed killer.

Any product containing glyphosate (i.e. RoundUp) plus a post-emergent broad-leaf herbicide can be used on dormant bermudagrass in January or February for winter weed control when temperatures are above 50°F.


Tree & Shrub

Select a freshly cut Christmas tree.  Make a new cut prior to placing in tree stand.  Add water daily.

Live Christmas trees are a wise investment, as they become permanent additions to the landscape after the holidays.

Light prunings of evergreens can be used for holiday decorations.  Be careful with sap that can mar surfaces.

Control overwintering insects on deciduous trees or shrubs with dormant oil sprays applied when the temperature is above 40°F in late fall and winter. Do NOT use "dormant" oils on evergreens. (EPP-7306).

If you did not treat young pines for tip borers in November, do so before March.


Apply winter mulch to protect rose bush bud unions and other perennials.  Wait until after several early freezes or you will give insects a good place to winter.

Poinsettias must have at least six hours of bright, indirect light daily.  Keep plants away from drafts.

Master Gardener Program of the Month:
Insect Adventure 2017

Plans are underway for our 2nd Annual "Exploring Insects with Tulsa Master Gardeners" event. On May 4, 2017, students across Tulsa County will have the unique opportunity to participate in fun and interactive activities in an effort to introduce children to the beneficial world of insects. BUT WE NEED YOUR HELP! In order to carry out our mission, we are seeking public donations to cover the cost of this amazing event. To learn more about the program and how you can contribute to this worthy cause, click HERE.

Poinsettia Care

Sales of Poinsettias in the U.S. will top $250 million in the six weeks leading up to Christmas.  That's a lot of green spent on a plant most people toss in the trash after the holidays.  But then again, can you imagine Christmas without Poinsettias?    So, the goal, then, is to keep your Poinsettias healthy and happy for at least six weeks. Click HERE to learn just how to do that!

Want Your Lawn to Look Great Next Year?  
Now is the Time to do Soil Testing

For you early planners, if you want the best looking yard in the block next year, now is the time to do your soil sampling.   Soil testing should be done every two to three years and it is very important to do so, particularly if you have been planting the same plants repeatedly in the same location within your garden.

The good news is . . . due to the very warm fall season, time still remains for you to take soil samples for both your lawn and garden areas.  Since the early to mid December ground temperature is still 40-45 degrees, you still have time to work into the soil any suggested changes you receive from your submitted soil sample(s), but you need to act soon. 

Have questions about soil sampling or need help taking a sample?  No problem!  Click HERE for a few suggested methods from OSU Extension for getting both the proper amounts and type of soil which is best for sampling.  If you sample and adjust for any nutrient deficiencies now, you will be glad you did come Spring!

Taking Care of our 
Feathered  Friends in the Winter

A shelter from the wind and cold, a dry bed and lots of warm drinks with delicious food . . . sounds like a recipe for a long, cozy winter. Or could this just be for the birds? Well, it is for all creatures, but let's talk about the birds.

There is a lot bird watchers can do to attract and protect birds in their own back yard in the winter. Click HERE to learn how.

Taking Care of the Tools in Winter That
Take Care of You in the Summer


As temperatures drop and we prepare ourselves for spending more time indoors, there's one additional outdoor project that you should do before you head indoors for the winter - winterizing your garden tools.  Click  HEREto learn how to k eep your garden tools sharpened, polished and cleaned to help you get a jump start on your landscaping duties early next year.

Southwest Tree Injury - Sun Scald

                          {Southwest Injury}                                            {Sunscald}

Human skin is not the only organism susceptible to the sun!  Winter sun and late summer sun can also cause significant tree trunk damage.

SOUTHWEST INJURY:    In January and February in Oklahoma, the damage is done when temperatures are below freezing, but the sun warms a portion of the southwest side of the trunk. When the sun sets, the trunk rapidly refreezes and kills the living cells. The result is discolored bark, cracking, sunken spots or sloughing of the surface bark to reveal dead tissue.

SUNSCALD:    In July and August, Sunscald causes the same destruction.  If a tree is newly planted or in a severe drought, transpiration (the method by which trees cool themselves) can be slowed.  The southwest side of the tree gets the most sun and will be affected.  Usually, there is no immediate bark cracking but, after a year or two, a flat side of the trunk will develop and new bark growth will push in from the side of the wound, pushing the old bark off the trunk. Trees usually survive this kind of assault, but the trunk is disfigured for years and can be a key source for insect infestation years later.

Trees with thin bark are at the greatest risk:  Ash, Beech, Birch, Cottonwood, Dogwood, Honey Locust, Linden, Mountain Ash, Oak, Sugar Maple, Oak, Tulip tree, Willow, and most fruit trees.

Management Strategies

  • Wrap the bark of young trees with commercial tree wrap or burlap or slit PVC pipe. Remove the wrap in spring. Or, provide shade for the tree with temporary fencing.
  • If you don't mind the look, tree trunks can be painted with white latex paint to reflect the sunlight. The light color will reflect light and slow warm up, delaying the bark from coming out of dormancy. Use indoor paint only.
  • Prune with care.  Avoid heavy pruning of older trees that would expose limbs and trunk that have been shaded to direct sunlight.  Gradually thin out limbs over several years.
  • Be sure and water at least 1 inch per week (or saturate to depth to 12 to 18 inches). Mulch the entire root zone.
For additional reading:

The Tulsa Master Gardener Foundation receives no city, state or federal funding for its programs. In fact, the majority of Tulsa's Master Gardener programs are self-funded.

Tulsa Master Gardener's own fundraisers make up most of the income to cover expenses. A significant portion comes from the Tulsa Master Gardener Annual Plant Sale that is held each April. Other fundraisers include the Garden Tour (June) and "Garage Sales" that occur from time to time. Finally, one other income source that sometimes gets overlooked are personal and corporate donations.  These are so important in helping to meet our financial obligations and are very much appreciated. 

Donations for this month include:

General Fund

Judi Hofer - Tulsa Master Gardener

Speakers Bureau Fund

Timberland Garden Club
Green Country Women:   Phyllis Robisch, President

Koi Pond Fund

Gary S. / Jimmie L. Mathews

Please consider making an online contribution HERE. For other information on how you can help support all that the Tulsa Master Gardeners do for their community, contact the Tulsa Master Gardeners Office by calling (918) 746-3701.  Thank you! 

Got a Question? Or Maybe a Soil or Plant Sample?
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Our Master Gardeners are on hand to assist you with even the toughest gardening questions. Visit us in person, by phone, via email or online! Hours of operation are Monday through Friday 9:00 a.m to 4:00 p.m.

Address: 4116 E. 15th Street, Gate 6 at the Fairgrounds
Phone: (918) 746-3701

Need More Information?
law n fertilizer
complex leaves
All about butterfly gardening in Tulsa County.

How to Take a Soil Test
How to collect a good sample of soil from your lawn or garden and get it tested at the OSU lab.

Once you have collected your soil test and gotten the results back, now what? Find out here. 

Show and tell.
Cool Season Lawn Care (Fescue)
12-month maintenance calendar.
State horticulturists, nurseries and growers pick favorite plants, shrubs and trees for use in the Oklahoma landscape. See the winners for this year and years past.

A list of recommended trees with descriptions. 

A list of over 60, by size and color.

Visit our demonstration garden on  15th Street, open 7 days a week. 

Current and historical source of rainfall, air temperatures, soil temps and much more. Click on Bixby station.  

                                    Like what you've seen
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