Garden Tips for December!

Lawn and Turf

  • Remove leaves from cool-season grasses or mow with a mulching mower. (HLA-6420)
  • Continue mowing cool-season lawns on a regular basis. (HLA-6420)
  • Continue to control broadleaf weeds in well-established warm- or cool-season lawns with a post-emergent broadleaf weed killer.

Trees and Shrubs

  • 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


  • 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.

Fruits and 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.


  • Keep all plants watered during dry conditions even though some may be dormant.
  • Irrigate all plantings at least 24 hours before hard-freezing weather if soil is dry. (HLA-6404)
  • Order gardening supplies for next season.
  • 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, garden books, magazine subscriptions, or membership to The Botanic Garden at OSU (
  • 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.
  • 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.

Garden Tips for January!

  • If precipitation has been deficient (1” of snow = ~ 1/10” of water), water lawns, trees, and shrubs, especially broadleaf and narrowleaf evergreens. Double check moisture in protected or raised planters.
  • 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.
  • If you did not treat young pines for tip borers in November, do so before March.
  • Check that gardening tools and equipment are in good repair—sharpen, paint, and repair mowers, edgers, sprayers, and dusters.
  • Inspect your irrigation system and replace worn or broken parts.
  • 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)
  • A product containing glyphosate plus a postemergent broadleaf herbicide can be used on dormant bermudagrass in January or February when temperatures are above 50°F for winter weed control.

Oklahoma Grown Christmas Trees

David Hillock

The best way to ensure that you are getting a fresh Christmas tree is to buy one directly from one of the many Christmas tree farms in Oklahoma. Each one offers a different experience, but one that is always a fun and memorable one for the family. Some of the farms offer more than just Christmas trees – wreaths, garland, table decorations and gifts may be available too. To make the experience more memorable, some also offer free hot cider, hot chocolate, coloring books and candy canes as well as children’s activities.

The Oklahoma Christmas Tree Association web site,, provides a list of farms currently selling Christmas trees as well as other information; currently there are 12 locations. These Oklahoma grown trees are beautiful, fresh, green Christmas trees which were carefully planted and nurtured for years specifically for you this Christmas. For more information about Oklahoma Christmas trees go to

Once you get your live tree home, it should be placed in water as soon as possible so it won’t dry out. A tree purchased from a Choose and Cut farm should be placed in water as soon as you get home. Do not let the stump dry out or you will have to make a fresh cut. A new tree will take up quite a bit of water the first few days so be sure to check the container or tree stand frequently and keep it full of water. Never let your tree get dry or it quickly becomes a hazard.


David Hillock

Paper white narcissus can add some bloom to the dreary winter days. The bulbs are some of the easiest for forcing as they do not require any chilling before they will bloom. Supplies needed include a low, flat container without drain holes that is anywhere from 3 to 5 inches deep, some gravel – 1/2 inch or less in diameter, bulbs, and water. Place the gravel in the bottom of the container filling to 1/2 to 3/4 full. Place the bulbs on top of the gravel so they are close to each other, but not touching. Fill in around the bulbs with gravel so that the bottom 1/2 to 1/3 of the bulb is covered and then fill the container with water so that the water level is just below the bottom of the bulb. If the bulbs actually sit in the water they will start to rot. Do not let the container run dry after root growth has begun as the roots will die if they are allowed to dry out. Place the container in a cool, dark place for about 3 weeks in order to get good root growth and then move it into an area with brighter light so the tops can grow. Turn the container daily so that the leaves do not have to stretch towards the light. When the paper whites start to bloom, move them to an area with filtered light so the blooms will last longer. This whole process takes about 6 weeks. Potting up a succession of bulbs every 2 weeks will insure bloom throughout the winter months.

Tool Cleanup

David Hillock

This is a good time to clean and sharpen tools before storing them for the winter. A little time now will ensure that they are ready to go as soon as it warms up in the spring. Shovels and hoes can be cleaned, sharpened at a 45-70 degree angle and coated with oil to prevent rust. If the tool has a wooden handle, it can be coated with a layer of boiled linseed oil to keep it weatherproof. Tools such as pruners, loppers and saws should be sharpened professionally unless you have the proper equipment to sharpen them.

Don't Forget to Water this Winter

David Hillock

Lack of adequate soil moisture is often a major cause of winter damage. Dry soil coupled with strong winter winds can cause havoc on a plant.  All plants, but especially narrowleaf and broadleaf evergreens, use water during winter. When little or no soil moisture is present, plants can become desiccated and it is more likely root damage will also occur.

When dry cold fronts are predicted, water the landscape at least 24 hours in advance of the front. Apply about ½ inch of water at the time of watering. A sunny day on moist soil helps warm the soil and root area thus reducing the amount of time the roots will be exposed to cold temperatures.

Moisture must be available below the frost line or frozen soil. When the soil freezes, if moisture is not present in soil pore spaces, moisture is pulled from plant roots to form the ice crystals resulting in desiccated roots, thus what some would refer to as “winter kill.”

Of course some common sense needs to be practiced at this time of year; do not allow the sprinklers to come on during a hard freeze. Ice forming on some plants could result in some serious damage and you could create a hazardous situation for you, pedestrians, or even passing vehicles.

Too much water can also result on problems during the winter. Cold wet soils can lead to rotting roots. Soils with more than ample moisture may also encourage winter weeds to germinate and flourish. Water only every three to four weeks and apply only enough water to moisten the top 6 or so inches of soil.

Do not forget plants growing in aboveground planters protected from rain. They need watering even in a wet season. Also, remember to water plants that are located under the eaves of a building or home since they often receive little natural precipitation.

Feeding Birds

David Hillock

It’s time to remember our fine, feathered friends for the winter months. If you already have birdfeeders, it’s a good time to clean them. Wash them in soapy water, then rinse in a 10% bleach solution and allow to dry completely.

It’s important to match your birdfeeders to the type of bird you want to attract. Smaller birds such as chickadee, tufted titmouse, and finches prefer the tube feeders. Larger birds such as cardinals and blue jays prefer hopper or platform feeders, and birds such as the morning dove eat seed on the ground. Just as people prefer different types of food, birds prefer different types of food. Thistle and black oil sunflowers are good for smaller birds, cardinals like sunflowers of all types and millet is good for ground feeding birds. A good general bird feeding mix is white proso millet and black oil sunflower. Suet is good for woodpeckers and nuthatches.

Water is also an important feature, not only for the birds to drink, but also to keep them clean as clean feathers insulate better from the cold weather. If you have a birdbath heater, be sure that it will shut off automatically when the water reaches about 40 degrees F so it doesn’t get too warm. It is also important to keep the water and the birdbath clean. For more information on attracting birds to the landscape see the OSU Extension Fact Sheet HLA-6435 Landscaping and Gardening for Birds.

 Continuing Education/In-service Opportunity for Master Gardeners and County Educators

David Hillock

Register now for the Horticulture Industry Show (HIS) on January 5-6, 2018. HIS provides an opportunity to learn more about vegetables, fruits, sustainable Ag, farmer’s markets, Christmas trees, and Master Gardener and Public Gardens. This year’s theme is Growing New Roots with Urban Agriculture. Cary Rivard, Fruit and Vegetable Extension Specialist at Kansas State University and Director of the Olathe Horticulture Research and Extension Center located near Kansas City, will be our keynote speaker.

 This year HIS will be held at the Tulsa Community College NE Campus, 3727 E Apache, Tulsa. All Master Gardeners and County Educators are invited to attend. If you are a returning Master Gardener you can receive Continuing Education hours that will count towards your recertification hours. If you are a County Educator you can receive in-service hours by attending.   

 Register today by going to the conference web site Registration before December 29 is $55 for the two day conference or $42 for Friday only or $25 Saturday only. After December 29 registration goes up to $75 for two days and $60 for Friday only and $35 for Saturday only so don’t delay and register before December 29.

 This should be another great conference, hope to see you there!

State Pecan Show 2017

Becky Carroll

It’s that time of year again! Remember to save back a couple of pounds of your best pecans to enter in the state show this year. Recently, we made a few changes to the list of classes. We removed several classes that hadn’t had any entries in the last several years such as Apache, Mahan, San Saba, Sioux and Success and added some that have had more entries but were only able to participate in the Other Cultivar class. The new classes are Oconee, Lakota, Waco, Nacono and Podsednik.

There are not any qualifying regional or district pecan shows. However, some county/area shows may be held at the discretion of the County Extension Educator. Winning entries from county shows will be sent to the state show. If no county/area show is available, growers may enter pecans directly by sending samples to Oklahoma State University, Department of Horticulture, Attn: Becky Carroll, 358 Ag Hall, OSU, Stillwater, OK 74078.  Samples should arrive by January 16, 2018. 

Samples should be entered in a sealed plastic or paper bag.  Label the bag on the outside and place a label inside the bag. Information should include exhibitors name and address, county, and type of pecan entered. Be sure to follow the guidelines that are listed below before sending entries. 

 A few helpful hints: Take the time to select pecans that are all the same cultivar, or same size and shape natives – don’t send mixed pecans.  Select uniform, clean, uncracked pecans. Presentation can make the difference between two very similar samples. Make sure to send 2 pounds of pecans in a labeled and sealed bag.

General Rules and Guidelines

  • All entries must be grown in Oklahoma during the current season.
  • Each entry shall consist of two pounds of nuts .
  • Entries deemed unworthy by the judges will not compete for awards.
  • Label each entry as to exhibitor’s name, address and cultivar of nuts.  If more than one native (seedling) pecan exhibit is made, identify the nuts from separate trees by numbers.  Only one exhibit of each cultivar or native tree may be entered by one individual.
  • Each entry will compete in one of the following 26 classes:
  1. Barton
  2. Burkett
  3. Cheyenne
  4. Choctaw
  5. Comanche
  6. Gratex
  7. Kanza
  8. Kiowa
  9. Lakota
  10. Maramec
  11. Mohawk 
  12. Nacono
  13. Oconee
  14. Pawnee
  15. Peruque
  16. Podsednik
  17. Schley (eastern)
  18. Shoshoni
  19. Squirrels Delight
  20. Stuart
  21. Waco
  22. Western
  23. Wichita
  24. Other Cultivars
  25. Large-Native (seeding) 60 nuts/lb or larger
  26. Small-Native (seedling) more than 60 nuts/lb
  • Each grower is allowed to participate at one county show of his or her choice.
  • Each grower is allowed to enter one entry in each show class with the exception of Class 24 (Other Cultivars), Class 25 (Large-seedling) and Class 26 (Small- seedling)
  • Each grower may enter one entry from each native (seedling) tree. 
  • Entries should be shipped or mailed to arrive at the show at least one day prior to the deadline. 
  • County pecan shows will not be affected by these rules and procedures.
  • Samples will be placed in cold storage, and judged before the Oklahoma Pecan Growers Annual Meeting.  At that time, the winning entries will be displayed with awards and recognitions.  All entries will become the property of the OPGA.
  • First, second, and third place winners in each class at the State Pecan Show will receive ribbons.
  • State Pecan Show Special Awards – Plaques will be awarded for the largest pecan entry, the entry having the highest kernel percentage, the champion native and the best entry of the show.
  • If a qualifying show is not available, growers may submit entries in accordance with these guidelines directly to the State Show.  Entries in the state show must be received by January 16, 2018 at the following address:

Oklahoma State University
Department of Horticulture and Landscape Architecture
Attn: Becky Carroll
358 Ag Hall
Stillwater, OK 74078

 2018 Pecan and Grape Management Class Brochures Available

Becky Carroll

The 2018 Pecan and Grape Management Course signups have begun. The brochures are available online at and Beginning in 1997 (pecan) and 2001 (grape), the OSU extension courses were set up to teach both new and experienced pecan and grape growers from around the state. The 2017 classes had 34 participants in the pecan class. The final class was held on October 17. The emphasis was on harvest and marketing our pecan crops. The last grape class met on September 7, where the 30 class members had the opportunity to tour Whispering Vines and Gander Way Winery. The unique mix of veteran, beginner and potential growers makes the classes beneficial to all no matter their experience level. We learn a lot and have a good time too!

With expert speakers from OSU, the Noble Foundation for pecan, and the pecan and grape industries, class members get a well rounded program of presentations and hands on activities. We appreciate all the expertise that these speakers provide.

The courses are scheduled so that management items can be addressed each month at the appropriate times. Class members have the opportunity to learn about growing pecan rootstock trees by actually participating in the process or planting and training new grapevines. Cimarron Valley Research Station personnel demonstrate equipment and share management techniques that are used at the site. Students learn about everything from business management to pest control to variety selection. Those class members with good attendance will receive a certificate of completion.

The fee for the 9 month course is $250 per person. The classes meet north of Perkins at the research station once a month from end of February through October for pecan, with the exception of June when participants are encouraged to attend the annual Oklahoma Pecan Growers’ Association meeting. The meeting times are on Tuesday afternoons from 1-5pm. Students also have access to the online pecan class and will receive details during the first class on how to access. Grape classes meet beginning in March through September on a Thursday afternoon from 1-5pm. County extension educators are welcome to attend the course for in-service credit. 

The 2018 pecan class will begin on February 27.  Deadline for registration is February 13. The 2018 grape class will begin March 1 with registration due February 15. If you would like to enroll in the class or you know someone that would benefit from brushing up their management skills, please have them contact Stephanie Larimer. Her email is and phone number is 405-744-5404. If you have other questions concerning the class, please contact Becky Carroll at

Arkansas Blackberry School

Becky Carroll

I recently found a great online resource for blackberry growers. It has several self-guided videos on the basics of commercial blackberry production. These recordings were made as a part of the Arkansas Blackberry School, a four part class held in Clarksville Arkansas in 2017. Funding was provided by the Southern Region Small Fruit Consortium. 

The four classes cover the major management activities and crop developments that happen in each season of the year. Follow along to learn how to set up, manage and grow your blackberry operation.


  • Basics of Blackberry Production with Dr. Amanda McWhirt
  • Variety Selection with Dr. John Clark
  • Pesky Winter Pests with Dr. Jackie Lee
  • How To: Winter Pruning  with Taunya Ernst


  • Blackberry Fertility Management and Trellising with Dr. Amanda McWhirt
  • Spotted Wing Drosophila and Broad mite Management in Blackberry with Dr. Donn Johnson
  • Pesky Spring Pests with Dr. Jackie Lee
  • How To: Spotted Wing Drosophila ID and trapping in Blackberry with Dr. Donn Johnson


  • Summer Tipping, Fruit Disorders and Irrigation of Blackberry with Dr. Amanda McWhirt
  • High Tunnel Blackberry Production with Dr. Elena Garcia
  • Consumer Preferences and Postharvest Handling with Dr. Renee Threlfall
  • Early Summer Pruning of Floricane Blackberries with Taunya Ernst


  • Interactive Fruit Budgets with  Leah English and Dr. Jennie Popp
  • Produce Safety with Dr. Amanda Perez
  • Weed Management in Blackberry with Dr. Nilda Burgos
  • Soil and Plant Tissue Nutrient Sampling of Blackberry with Dr. Amanda McWhirt
  • How To:  Identifying Anthracnose in Blackberry with Sherrie Smith 

Horticulture "Spray Day" - Thursday, March 8, 2018

This event will be held at the Cimarron Valley Research Station and open to anyone interested. Emphasis will be on equipment demonstrations for different crops and different sizes of operations; question and answer times; sessions on calibration, worker protection standards, pesticide certification requirements and pest management.  We hope to have vendors with different types of equipment and chemical representatives in attendance. Sponsored by Oklahoma State University Horticulture and Landscape Architecture Department, Oklahoma Field Research Service Unit, Noble Research Institute, Oklahoma Pecan Growers, Oklahoma Grape Industries Council, and Oklahoma Fruit and Vegetable Growers.

Horticulture Tips - 2017 Index

  • All-American Selections Presents both Regional and National Winners for 2017, 04/17
  • Attracting Birds to Landscapes and Outdoor Areas, 08/17
  • Brown Patch Disease of Cool-Season Grasses, 07/17
  • Collecting and Using Landscape and Garden Waste, 08/17
  • Controlling Deer Damage, 10/17
  • Controlling Insects In and Around the Home, 10/17
  • Controlling Winter Annual Weeds, 08/17
  • Cool-season Lawn Planting and Renovation, 08/17
  • Cover Crops, 10/17
  • Diagnosing Problems in the Landscape and Garden, 07/17
  • Dividing and Replanting Iris, 07/17
  • Dividing Perennials, 08/17
  • Don’t Forget to Water this Winter, 12/17
  • Fall – A Good Time to Control Broadleaf Weeds, 10/17
  • Fall is for Planting Trees and Shrubs, 08/17
  • Federal Marketing Order for Pecans Now in Place, 10/17
  • Feeding Birds, 12/17
  • Fruit Elimination on Ornamental Trees, 02/17
  • Garden Tips for February, 02/17|
  • Garden Tips for March, 03/17
  • Garden Tips for April, 04/17
  • Garden Tips for May, 05/17
  • Garden Tips for June, 06/17
  • Garden Tips for July, 07/17|
  • Garden Tips for August, 08/17
  • Garden Tips for September, 09/17
  • Garden Tips for October, 10/17
  • Garden Tips for November, 11/17
  • Garden Tips for December and January, 12/17
  • Growing Fall Irish Potatoes, 08/17
  • Growing Transplants Indoors, 03/17
  • Help! Weed are Taking Over the Garden, 08/17
  • House Plant Pests, 10/17
  • Insect Hotels:  Good Bugs Check In AND They Check Out, 06/17
  • It’s the Dirt, 05/17
  • March Weed Control Tips, 03/17
  • Mulch, Mulch, and More Mulch!, 05/17
  • Narcissus, 12/17
  • New Invasive Blackberry Pest for Oklahoma – Broad Mites, 07/17
  • Oklahoma Grown Christmas Trees, 12/17
  • Oklahoma Proven Selections for 2017, 02/17
  • Ornamental Sweet Potatoes – Are They Edible?, 10/17
  • Pecan Graftwood Sources, 02/17
  • Plant Spring-Flowering Bulbs Now!, 10/17
  • Protect Tree Trunks During Summer, 06/17
  • Protecting Young Trees, 10/17
  • Pruning and Staking Tomatoes, 06/17
  • Pruning Roses, 03/17
  • Raking Basics, 10/17
  • Rehabilitation or Removal?, 05/17
  • Selecting New Vegetable Crops, 04/17
  • Spring Irrigation System Inspection, 03/17
  • Thrips can Wreak Havoc on Flowers and Plant Foliage, 05/17
  • Tomato Blossom Drop or Poor Fruit Set, 06/17
  • Tomato Cages, 04/17
  • Tool Cleanup, 12/17
  • Using Bedding Plants in the Landscape, 04/17
  • Watering Time Affects Slug Population, 04/17
  • Watering the Yard and Garden Efficiently, 07/17
  • Winter Annual Weed Control: Henbit and Carolina Geranium, 02/17
  • Winter Damage to Broadleaf Evergreens, 03/17
  • Working with Mother Nature, 05/17
  • Year of the Daffodil, 03/17





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