November-December 2011 / Volume 57     

In This Issue
November-December Lawn and Garden Tips
Don't Throw Out Those Leaves!
What Tree is Tops for the Urban Landscape?
Another La Niña Develops
Ask A Master Gardener

Weather Stats for Gardeners

Soil Temperature 2" below sod:   

59 degrees 


Rainfall total last 30 days:  

2.21 inches


4 Ways to Contact Us
Email us at:

See our website at: 

Call: 746-3701 from 9-4, M-F 
Visit us at 4116 E. 15th Street, Gate 6 at the Fairgrounds

Whether you call or bring samples of plants to the office, trained Master Gardeners will answer your gardening questions with science-based information.
Need More Information?

Click on any of the links below:


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.
How to Plant a Tree in Oklahoma Soil
Show and tell.
Fescue Lawn Care
12-month maintenance calendar.
Bermuda Lawn Care
Ditto above.
Trees for Tulsa
A list of 50 recommended trees with descriptions.
Crape Myrtles
A list of over 60, by size and color.
Oklahoma Proven Plants
The new list for 2011. State horticulturists, nurseries and growers pick their favorite plants, shrubs and trees.
Current and historical source of rainfall, air temperatures, soil temps and much more. Click on Bixby station.  

Back Issues  

Past issues of our eNewsletters can be read and downloaded.

Become a Master Gardener

Classes start in September. Register for more information.

Oklahoma State University, in compliance with Title VI and VII of the Civil Rights Act of 1964, Executive Order 11246 as amended, Title IX of the Education Amendments of 1972, Americans with Disabilities Act of 1990, and other federal laws and regulations, does not discriminate on the basis of race, color, national origin, gender, age, religion, disability, or status as a veteran in any of its policies, practices or procedures. This includes but is not limited to admissions, employment, financial aid, and educational services.
Lawn and Garden Tips


  • Build a compost bin and learn the easy steps to successful composting. See fact sheet BAE-1744 for instructions.
  • After vegetable harvest, make sure all insect and disease carrying plant trash is collected and disposed of. Insects such as squash bugs over-winter in plant trash.


  • Don't send your falling leaves to the landfill. Shred and use as garden mulch, add them to your compost pile or use a mulching lawn mower and shred them completely into your lawn. See article below for more information. 
  • November is the time to give your fescue lawn one last fertilizer application. Use one to 1-1/2 pounds of nitrogen per 1,000 sq. ft.
  • Fescue should have one inch of moisture per week. Mow at 2-½ to three inches.
  • For problem broadleaved weeds that sprouted in your newly seeded fescue, herbicides with 2,4-D (Weed-B-Gon, Trimec) may be used after the third mowing of new fescue. Always read and follow labeled instructions. For more information and identification see fact sheet HLA-6601


  • Leave foliage on mums and other perennials to help insulate crowns from winter freezes.
  • Tulips can still be planted through the middle of November. For more information, click here
  • Leftover garden seeds can be stored in an airtight container in the refrigerator or freezer.
  • Clean your garden tools before storing them for the winter.  Apply a thin coat of oil to prevent rust. Drain fuel tanks or add a stabilizer according to directions. Drain garden hoses and bring inside. 
  • Make sure your shrubs and perennial plants go into winter with deep, moist soil. Water before predicted hard freeze.  This is especially important for evergreens and foliage under leaves that rain doesn't reach.
  • Wrap young, thin barked trees with a protective tape to prevent winter sun scald. The wrap is available at nurseries and garden centers.
  • Deciduous trees can be pruned in winter if needed. (Delay pruning fruit trees until next February or March.)
  • Routine pruning is best done late winter and early spring. (Spring bloomers such as azaleas should be done immediately after flowering in spring.)
  • You can continue to plant balled and container grown trees.  Be sure young trees are well watered going into winter. See article below for suggestions for the home landscape. 

LeavesDon't Throw Out Those Leaves!   

autumn leaves Most everyone loves trees. Unfortunately, when leaves depart their residence in the trees and fall on your lawn, it turns into work with all of the raking and bagging and hauling out to the trash. Plus, it fills up the trash bin and our landfills. But, before you pick up that rake...there is something better that can be done.


In fact, tree leaves should be considered an asset and not sent to the landfill. They contain valuable nutrients and organic matter for your garden beds. Many communities across the country prohibit leaves and yard clippings from being added to household trash, recognizing the expense to the city and value to the homeowner.

For example, did you know that mowing leaves into healthy Oklahoma lawns will not harm them? This should be done by shredding leaves with a mulching mower until none are left on top of the grass. One might think that mowing leaves into the lawn would contribute to disease and thatch buildup, but that is not the case at all. Mulching actually adds beneficial nutrients and organic matter to the soil, thus saving on fertilizer. And, studies have proven that mowing up to six inches of leaves into turf grass had no undesirable effect on growth, appearance, or general health of lawns.


Fallen leaves can also serve as mulch for the flower beds, because as they decompose, they release nutrients and add organic material to the soil. Like all mulches, the leaves will also help conserve water, moderate ground temperature and prevent weed growth. However, it is best to wait and apply any type of mulch until after frosts occur but before any hard freezes occur.  This allows the soil temperature to drop at a similar rate to the air temperature, which allows shrubs and trees to go into a natural dormancy state at the proper time.


Leaves tilled into the soil of your vegetable garden will benefit both sandy and clayey soils. It will slow down drainage in sand and speed it up in clay. There are also beneficial effects on the handling of nutrients and making the soil more plant friendly.


Finally, leaves are a very good source of compost material. While whole leaves break down quite slowly, chopped leaves mixed with other compost material (grass clippings, vegetables scraps, etc.) will decompose about four times as fast as they would normally. As for partially rotted leaves, or leaf mold, they have a chemical makeup that is the closest thing in nature to pure humus.


Harvesting the assets of your leaves is a win-win situation for both you and the city's landfill.  So, do your lawn and local landfill a favor; don't throw out your leaves!.

TreesWhat Tree is Tops for the Urban Landscape? 

Many local residents have lost trees over the last several years due to ice storms, extremes in temperatures, and drought. When looking to replace a tree on a residential lot, what type of tree will meet space challenges and blend successfully into the landscape? According to David Hillock at OSU Extension Horticulture Department, small- to medium-sized trees are the best choice. He comments that, "There are many species that have wonderful ornamental characteristics and still provide shade and privacy." Here are a few to he recommends the home owner might consider:

Small Trees (10-25 ft tall) 

Amur Maple (Acer tataricum spp. ginnala)
Buckeye (Aesculus spp.)
Chastetree (Vitex negundo)
Crapemyrtle (Lagerstroemia indica)
Deciduous Holly (Ilex decidua)
Desertwillow (Chilopsis linearis)
Flowering Dogwood (Cornus florida)
Hawthorn (Crataegus spp.)
Japanese Maple (Acer palmatum)
Oklahoma Redbud (Cercis canadensis ssp. texensis 'Oklahoma')
Rose-of-Sharon (Hibiscus syriacus)
Saucer Magnolia (Magnolia x soulangiana)
Serviceberry (Amelanchier spp.)
Shantung Maple (Acer truncatum)
Smoketree (Cotinus spp.)
Star Magnolia (Magnolia stellata)
Winterberry (Euonymus bungeana)
Witchhazel (Hamamelis spp.)
Yaupon Holly (Ilex vomitoria


Medium Trees (25-40 ft tall)
American Hornbeam (Carpinus caroliniana)
Cedar Elm (Ulmus crassifolia)
Chinese Pistache (Pistacia chinensis)
Chittimwood (Bumelia lanuginosa)
European Hornbeam (Carpinus betulus)
Goldenraintree (Koelreuteria paniculata)
Hedge Maple (Acer campestre)
Ironwood (Ostrya virginiana)
Japanese Pagoda tree (Sophora japonica)
Washington Hawthorn (Crataegus phaenopyrum)
Western Soapberry (Sapindus drummondii)
Whiteshield Osageorange (Maclura pomifera 'Whiteshield')


For more suggestions for the Oklahoma landscape, see the Oklahoma Proven award winners for Trees, Shrubs, Perennials, and Annuals. 

Another La Niña Develops:
More Drought Ahead?  

Hopefully, you have all had a chance to get out and enjoy the many beautiful autumn days we have been blessed with this year, especially after a nightmare of a summer! Nice as the weather has been the last couple of months, we are still hurting for moisture in the Tulsa area...we remain about 10 inches short for the year to date...and the latest winter outlook from the Climate Prediction Center is not at all encouraging, with the odds favoring below normal precipitation. The main culprit, our old friend La Niña, appears ready for an encore performance! The outlook is for this La Niña to be weaker than last year's event, which was considered a high-end moderate La Niña. This means that a weak or moderate La Niña is the most likely outcome.


The tendency for drier than normal winter seasons over the southern U.S. during La Niña events is well documented, and was observed last winter from Texas through much of the South...Tulsa included despite record snowfall. If we examine all La Niña winters since 1950 (18" all), and break them down by the strongest, weakest and middle third of events based on the Oceanic Niña Index, we find that winter seasons during moderate to strong La Niña events do show a tendency toward either near or above normal temperature. However, the precipitation trends are much less clear. Moderate events have actually shown a small tendency toward above normal precipitation...that is until last year! One interesting trend with weak La Niña events is the strong tendency for below normal winter temperatures at contrast to moderate and strong events. Keep in mind that this is a very small sample size and thus the data should be used with caution.


La Niña is not the only factor that determines the seasonal outlooks, as current trends are also part of the equation. It is also worth noting that this area actually is a bit overdue for a multi-year drought like the ones observed during the 1930s and 1950s.


So the best course of action for area gardeners would be to prepare for a dry winter, and don't forget to keep things watered. Lack of adequate soil moisture is often a major cause of winter damage. And should this winter be wet, we can all be pleasantly surprised! For info on winter protection of landscape plants: HLA-6404.

Question: I would like to use my oak leaves as mulch but I have heard that they will make the soil too acid. What should I do with them?
Answer: The myth that oak leaves cause soils to be acidic continues to circulate and is often perpetuated by experienced gardeners. Oak leaves do not cause soils to be acid. This was documented at the University of Connecticut where they yearly tilled into the soil 6 inches of oak leaves and found no significant effect on pH (acidity) after several years.

Click here to send your question to the Tulsa Master Gardeners or see Answers to other Questions on the Web site