Oklahoma Cooperative Extension Service Division of Agricultural Sciences and Natural Resources Oklahoma State University


David Hillock, Consumer Horticulturist

Lawn & Turf

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

Tree & 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 & Nuts

  • Cover strawberry plants with a mulch about 3-4 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.
  • 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, bird feeders, 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.
  • 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.



  • 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.
  • 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.

Christmas Trees by David Hillock

Today there are several options when it comes to choosing a Christmas tree including cut trees, potted or balled trees, and artificial trees. Cut, live trees are the most common type of Christmas tree. Three options are available to a person wanting a cut Christmas tree ---a pre-cut tree purchased from a dealer, a choose-and-cut tree purchased from a local grower, or a wild-grown native Christmas tree.

Cut Trees – Great care needs to be taken in selecting a pre-cut tree. Most pre-cut Christmas trees sold in Oklahoma are grown in the Lake States and the Pacific Northwest and may have been cut as early as August. However, some trees are locally grown and thus will be fresher and less prone to drying out too quickly. As soon as a Christmas tree is cut it begins to dry. A tree that has dried will not recover when placed in water and is a fire hazard. Dry trees also tend to lose needles.

Follow these steps to be sure that the tree you are buying is fresh and of high quality.

  1. Gently pull on the needles. They should be tightly attached to the twig.
  2. Shake the tree vigorously or bounce the butt on the ground. If green needles fall, look further. Dead, brown needles falling from the inner part of the tree are older needles and are less of a problem.
  3. Check to see that the tree has a fresh, green color. Some trees are sprayed with a blue-green dye. This dye is harmless, but be sure it's not hiding a dry tree. Some trees like scotch pine tend to be light green in color during colder weather, but will darken up once moved indoors.
  4. Buy early before all the desirable trees have been sold.
  5. Fir and pine trees hold needles better than spruce trees.
  6. Break a few needles. They should be flexible and will feel moist or possibly sticky. They should also be fragrant when crushed.
  7. Be sure limbs are strong enough to support lights and ornaments. Limbs should also be well placed to give the tree a pleasing shape. Minor defects can often be turned toward a wall and can lower the purchase price.
  8. Ask the dealer if the tree was locally grown. Local trees are much more likely to be fresh because they are cut nearer Christmas and aren't shipped long distances.

Choose-and-cut trees are available from Christmas tree growers throughout Oklahoma. Trees available from Oklahoma growers include Virginia pine, Scotch pine, eastern white pine, Austrian pine, ponderosa pine, white pine, Norway spruce, and concolor fir.

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.

A free marketing directory produced by the Oklahoma Christmas Tree Association shows 15 different farms across the state in 2014.  The 2014 marketing directory lists members of the Oklahoma Christmas Tree Association with trees for sale this holiday season.  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 or contact your local Extension office.

Buy a choose-and-cut tree the way you would a precut tree. Freshness and health are still the most important characteristics. The grower will usually have many trees marked for sale in various sizes. Some growers will cut the tree for you and others will expect you to cut your own.

Native trees can also be used as a Christmas tree. If you cut your own native Christmas tree, be sure you get the landowner's permission. Trespassing is illegal, even to cut what may be an unwanted tree.

Potted or Balled Trees – Some people buy a potted or balled Christmas tree with roots intact in the hope of having a new landscape tree come spring. This is very difficult to do successfully, but your chances of success increase if the tree is treated right.

  1. Buy a healthy tree from a reputable nursery or grower. Expect to pay a higher price than for a typical Christmas tree.
  2. Keep the tree in a shaded area or a non-heated garage until it is brought inside.
  3. Keep the soil in the ball or pot moist until well after it is transplanted after Christmas. A frozen ball need not be watered if the crown is shaded and protected.
  4. Lift and carry the tree by the ball or pot, not the top.
  5. Keep the tree in the house no longer than about one week, five days or less is even better.
  6. Have the tree's planting hole dug before the soil freezes and keep the fill dirt thawed. The planting hole and backfill can be protected from freezing by covering with plastic and then a thick layer of straw.

Artificial Trees – Artificial trees must be used carefully. Electric lights should not be used on metal trees because of the danger of electric shock. Light these trees with off-the-tree spotlights. Plastic trees may be fire resistant but the fumes they give off when burned are toxic.

Cut Tree Care – To insure a safe and happy holiday, you need to know a few things about caring for Christmas trees.

Once you have chosen a fresh Christmas tree, do your best to keep it fresh. A tree can stay fresh and healthy for several weeks if it is well cared for.

  1. When you get the tree home, cut about an inch off of the butt end to aid in water absorption. Get the cut end into a container of plain water quickly. There is no need to add aspirin, sugar, or flame retardant to the water.
  2. If the tree is not set up right away, store it in a protected, shady, unheated area. Cut the end and place the tree in a bucket of water.
  3. When the tree is brought into the house, saw a slice of the butt again to insure water absorption.
  4. Use a sturdy stand with a large water reservoir so it won't dry out. A fresh tree can use 1 quart or more of water a day, so water daily. A tree is beginning to dry out if its water use slows or stops.
  5. Keep the tree away from heat sources such as fireplaces, TV's, radiators, and air ducts. Never have open flames on or near a Christmas tree.

Decorating the Tree – Use only electric lights on your tree, never candles. Lights and cord should have the Underwriters Laboratories safety seal. Discard old damaged Christmas lights. New lights are relatively inexpensive, use less electricity, and stay cooler than old lights. Follow directions to determine how many strings to put on one circuit. Be sure to turn off the tree lights when no one will be in the room for any length of time.

Tree Disposal – Christmas trees can be useful even after they are taken down. Trees can be placed in the yard to add greenery and act as a bird haven until spring. Tie fruit peelings, popcorn or other favorite bird snacks to your tree for bird feed. Christmas trees can be used for firewood or chopped up and used as mulch. The branches can be cut off the tree and used as a mulch to protect landscape plants as well. Many communities have programs to gather trees after Christmas to be chipped for mulch or other uses. Trees can also be used to create a fish attractor by weighting the base of the tree and sinking it in a pond.

Poinsettia Care by David Hillock

Newer cultivars of poinsettia, in addition to being very showy, have excellent keeping quality and stronger stems than older cultivars. When buying your poinsettia, choose a plant with well-expanded, well-colored bracts. Foliage should be medium to dark green with uniform coloring. Flowers should be present in the center of the bracts.

  1. After you purchase your plant, do not expose it to chilling temperatures or cold drafts of air. If the temperature out­doors is below 50°F do not carry an unwrapped plant from the retail shop to your car. In the home or other place of display, avoid cold drafts and excessive heat from heating ducts, TV sets, or large incandescent lamps. Temperatures of 70°F or below (down to 55°F) are desirable to retain best bract color. Large plants can be placed on the floor if light is adequate.
  2. Light plays an important role in retention of leaves on the plant. Place the plant in an area where it receives at least six to eight hours of direct natural or artificial light. A minimum of 75 foot candles is desirable where pos­sible. This would be similar to the minimum light intensity required for good desk lighting in an office. Incandescent lights such as those found in most homes will give a truer, brighter bract color than most types of fluorescent light.
  3. Poinsettias can be displayed with other houseplants. The adjacent plants raise the humidity and allow poinsettias to last longer. Also, the regular houseplants can be spruced up for the holidays.
  4. Many commercial growers use non-soil mixes of sphag­num peat, pine bark, vermiculite, perlite, or similar ingredients. When plants are grown in such non-soil mixes, it is sometimes difficult to decide when the plant needs water. If there is no heavy component (sand or soil) in the mix and a plastic pot is used, the pot can be lifted to determine its weight. If the plant is heavy, there is usually plenty of moisture in the pot; if it is lightweight, the medium is dry and a thorough watering should be given. Moisture needs can also be assessed by feeling the growing medium in the pot. Water when the top of the growing medium is starting to feel dry, but do not allow too much drying. Slight wilting of the plant is not harm­ful, but avoid severe wilting, which will cause leaves to drop. Water the plant thoroughly. Make sure a small amount of water drips through the drainage holes of the container. If the plant is wrapped with decorative foil, punch a hole in the foil beneath the pot to allow excess water to escape. The plant should be placed on a saucer to prevent dam­age to the furniture or carpet.  Do not water the plant too frequently when the soil or growing mix is already wet or this may result in roots suffocating from lack of oxygen, causing the leaves to wilt, yellow, and drop.
  5. Recent research has shown that poinsettias are not poi­sonous, but the plants are intended solely for ornamental purposes. Some people are allergic to the milky sap and may develop a rash when exposed to the sap. Avoid breaking the leaves and stems, as this will release the sap. It is wise to keep any houseplant out of the reach of small children and pets.

Pecan Harvest and Storage by Becky Carroll, Extension Assistant

This time of the year people are out and about picking up pecans to make their Christmas treats. Remember the earlier you can harvest, the less likely that crows, bluejays and squirrels will be taking their share. As soon as the shucks open, the pecan is ripe and ready to be harvested.

Dry the pecans until they will snap when the kernel is broken in half. If it is rubbery, it needs more drying time. A few days with a fan will dry them down to a good moisture level for storage. When the pecans are dry, either take to a custom cracker or freeze the nuts in the shell.

Just a note about cracking pecans, keep in mind that if you take 10 pounds of pecans to be cracked, you will end up with about 5 pounds of nutmeats. The higher quality pecans will have higher kernel percents or more nutmeat to shell and packing material. If the pecans are not filled out completely and have very thick shells, your nutmeat yields will be less. Pecans usually range in kernel percent from 40-58% kernel.

If left at room temperature, pecans will become rancid. Pecans have a high oil content and these heart healthy oils will begin to spoil in about 3 months. If properly handled, pecans can be stored for many years. Pecans should be stored in an airtight container in the freezer. They can absorb other flavors from the freezer and should be kept in freezer bags or containers. Unshelled pecans will hold their quality longer but shelled pecan kernels can be frozen successfully for 2-3 years.

Pruning Tree Fruit and Small Fruits by Becky Carroll

After the first hard freeze in the fall and following leaf drop, some people have the urge to get out and start pruning their trees or plants. However, on some fruits, it’s best to wait until late in the winter or very early spring to begin.

In the blackberry patch, homeowners can clear out any old floricanes (canes that fruited this year) and remove canes with visible redneck cane borer damage, taking care to remove and destroy infested canes. The blackberries will eventually need to be thinned out to 3-5 canes per plant and lateral branches cut back to about 12-18 inches long.

In the grape vineyard, it’s best to wait until March to start the pruning routine. If vines are pruned early and everything but the spurs are removed, there is nothing to absorb any freeze damage that might occur. Normally on a grapevine, freeze damage will start at the end of the shoot and progress upward toward the cordon. If it is already removed, the spurs will take the brunt of the damage. Just be sure to have pruning completed before the buds begin to swell and are easily damaged during the pruning process. Grape growers with large vineyards can begin early by removing unwanted canes and leaving long canes where they will want spurs. A second pruning will need to be done later to take the long canes back to the needed number of buds.

If possible, wait until bloom time to prune peach trees to be able to adjust pruning level to the amount of crop present. If there are a large number of blooms, more pruning can be done to open up the tree and keep at the desired height. If buds have been damaged due to cold injury and there are few blooms, less pruning can be done to increase production. The main goals of pruning a mature peach tree should be to keep the open vase structure with no upright crossing branches and to keep the tree at a convenient height to improve picking ease.

Deicing Affects on Landscape Plants by David Hillock

Cold temperatures usually bring ice and snow making it difficult to travel for both motorists and pedestrians. Public safety during this time is a high priority and usually addressed by the use of deicing compounds. While these deicing compounds make it safer for us, they often damage concrete surfaces, automobiles and landscape plants.

There are several deicing compounds, each with pros and cons.

Sodium chloride (NaCl) is the most common and known as table or rock salt. It is the least expensive, most widely used and is most effective when temperatures are above 15°F. Unfortunately sodium chloride is very corrosive and damaging to landscape plants and excessive sodium in the soil can destroy its structure.

Calcium chloride (CaCl2) dissolves readily, acts quickly and is effective in very cold temperatures - down to -20°F. It is, however, highly corrosive to concrete and metals, but slightly less damaging to plants than sodium chloride.

Potassium chloride (KCl) is a natural material used for fertilizer, but is highly corrosive as a deicer. It is less damaging than sodium chloride to plants.

Calcium magnesium acetate (CMA) is an environmentally friendly compound derived from dolomitic limestone and acetic acid. CMA is considered safer for plant material, non-corrosive to concrete surfaces and biodegradable. It is also effective at melting ice to around 15°F. The downside, it is 30 to 40 times more expensive.

Deicing materials are salts that melt ice, creating a brine solution (salty water) which freeze at lower temperatures. The problem in the landscape occurs when this brine solution is splashed onto plant foliage or runs off pavement into the soil. An accumulation in the soil near plant roots results in damage to the plants. Plants suffer a salt-induced water shortage, even though there may be moisture in the soil, because roots are unable to absorb sufficient water.

To minimize damage by deicing materials in the landscape consider the following approaches:

  • Mechanical removal – the less ice and snow present, the less deicing material needed.
  • Use abrasive materials in conjunction with mechanical and/or deicing materials – abrasives such as sand have few impacts on the environment. They do not melt ice, but do improve traction on slippery surfaces.
  • Plan ahead – plant salt tolerant plants in areas receiving large amounts of deicing material; locate salt sensitive plants away from areas deicing materials are used; use hardscapes (gutters, barriers) to channel runoff away from planting areas; do not pile snow containing deicing materials onto planting areas; and irrigate once heavily in the spring to leach salts away from root zone.

Winter Irrigation by David Hillock

Don’t forget to water your landscape plants during the winter months. It is not uncommon to have several weeks without precipitation during the winter, and though most plants are in a dormant state, they still use water, especially evergreens. If a cold front with freezing temperatures is forecasted, water the landscape at least a couple days in advance. Moist soil is better able to provide plant roots protection from sudden drops in temperatures than dry soils are; water only when temperatures are well above freezing during the day and avoid overspray or runoff onto streets and sidewalks that could freeze at night and become a hazard to motorists and pedestrians.

Pay particular attention to plants in raised beds, plants in areas that are protected from precipitation such as under large overhangs, and broadleaf evergreen plants. During dry winters, broadleaf evergreens should be watered once a month.

Pecan Graftwood Collection by Becky Carroll

Although grafting time isn’t until April or May, growers need to be thinking ahead if they want to collect their own graftwood. December through February is the time to collect graftwood for pecan propagation. Graftwood should be gathered while the buds are fully dormant. Mid to late December is a good time to collect the wood. At this time, the wood is dormant but normally temperatures haven’t been cold enough to cause damage to the shoots.

Fact Sheet HLA-6217 - Collecting and Storing Pecan Propagation Wood details the procedure. Be sure to select graftwood the size needed for the particular type of grafting to be done in the spring or take a variety of sizes to be stored. Collect one variety at a time and store properly. If the graftwood dries out or molds, propagating success will be limited.

Graftwood can also be purchased. A new graftwood supplier list will be available in February.  Look for it in the February issue of Horticulture Tips or on the pecan webpage –

2015 Grape Management Course by Becky Carroll

A brochure detailing the 2015 Grape Management Course is available online at The course offers an opportunity for potential new or veteran growers to learn or refresh their basic management skills needed to successfully grow grapes. The class meets one afternoon a month beginning March 5 and continuing for the growing season. Having the classes throughout the season gives participants the chance to see what management requirements are necessary at specific times. Students learn in both the classroom and vineyard setting. The classes meet at the Cimarron Valley Research Station near Perkins. Classes also travel to a couple of established vineyards/wineries to learn from other growers.

The cost for enrollment is $250 per student. Registration for the grape course is due by February 25, 2015. County extension educators are encouraged to enroll in the course free of charge.

2015 Pecan Management Class Taking Enrollments by Becky Carroll

The 2015 Pecan Management Course signups have begun. The brochure is available online at Reaching almost 500 students over the past 17 years, the OSU extension course is set up to teach both new and experienced pecan growers from around the state. The 2014 class had 23 participants from around Oklahoma and one Texan.  The final class was held on October 21, 2014. The emphasis was on harvest and marketing our pecan crops. The unique mix of veteran, beginner and potential growers makes the class 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, and the pecan industry, class members get a well rounded program of presentations and hands on activities. We appreciate all the expertise these speakers provide.

The course is scheduled so that management items can be addressed each month at the appropriate times. Class members have the opportunity to learn about growing rootstock trees by actually participating in the process. Each month students can see the progress of the growth and in October have seedling trees to take home and establish.  Cimarron Valley Research Station personnel demonstrate equipment and share management techniques that are used at the site. Students also have the opportunity to learn to graft in a nursery area on the station where they can see how successful they were at the following classes. 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 March through October, 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. County extension educators are welcome to attend the course at no charge. 

The 2015 class will begin on March 10.  Deadline for registration is February 27. 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

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

It is not too late to register for the Horticulture Industry Show (HIS) on January 16-17, 2015. HIS provides an opportunity to learn more about vegetables, fruits, sustainable Ag, farmer’s markets, landscape horticulture, Christmas trees, Master Gardener and Public Gardens, and Agritourism.

This year HIS will be held at the Holiday Inn City Center, Ft. Smith, AR. 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 the minimum 20 hours you need to keep active member status.  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 24 is $50 for the two day conference or $37 for one day.  After December 24 registration goes up to $80 for two days and $45 for one day so don’t delay and register before December 24.

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

Horticulture Tips - 2014 Index

All-America Selections for 2014, 04/14
All-America Selection Winners for 2014, 08/14
Alternatives to Japanese Maples, 11/14
Beneficial Fungi, 06/14
Best Turfgrass Management Practices for Environmental Protection, 11/14
Christmas Trees, 12/14
Container Planting Tips, 05/14
Cover Crops, 10/14
Day Camp Ideas, 06/14
Deicing Affects on Landscape Plants, 12/14
Discover What Your Fertilizer Needs are During July, 07/14
Dividing and Replanting Iris, 07/14
Dothistroma Needle Blight of Pine, 05/14
Fall Leaf Lettuce Trial, 05/14
Free Resources for Youth Horticulture Education, 09/14
Fresh Strawberries from the Garden, 05/14
Garden Tips for February, 02/14
Garden Tips for March, 03/14
Garden Tips for April, 04/14
Garden Tips for May, 05/14
Garden Tips for June, 06/14
Garden Tips for July, 07/14
Garden Tips for August, 08/14
Garden Tips for September, 09/14
Garden Tips for October, 10/14
Garden Tips for November, 11/14
Garden Tips for December and January, 12/14
Graftwood Sources, 02/14
Houseplants Improve Indoor Air Quality, 02/14
Irrigation System Maintenance: Spring Start Up, 03/14
Is it too late to apply glyphosate herbicide for winter annual weed control in bermudagrass, 03/14
Late Summer Color, 09/14
Low Temperatures Bring Possibility of Increased Winter Injury to Bermudagrass Stands, 02/14
Moving Plants Indoors for Winter, 09/14
Mulch, Mulch and More Mulch!, 05/14
Natural Air Filters, 09/14
Oklahoma Proven Selections for 2014, 02/14
OSU Horticulture Research: Public Acceptance of Reclaimed Water Use in Oklahoma, 11/14
Pecan Crop Load, 08/14
Pecan Graftwood Collection, 12/14
Pecan Harvest and Storage, 12/14
Pecan Webpage Improvements, 10/14
Performance of Determinant Tomato Varieties for Hot Weather Production, 08/14
Perennial Plant of the Year for 2014, 03/14
Planting Fall Vegetables, 07/14
Poinsettia Care, 12/14
Propagating Southern Magnolia Seeds, 10/14
Protect Tree Trunks During Summer, 06/14
Protecting Bulbs from Squirrels, 11/14
Pruning and Staking Tomatoes, 06/14
Pruning Tree Fruit and Small Fruits, 12/14
Read the Label “Before” You Purchase a Pesticide!, 07/14
Recycling Tomato Cages, 11/14
Repairing Tree Injury, 05/14
Save Water this Summer!, 08/14
Smart Irrigation Technology, 10/14
Soil Testing for Vegetable Crops, 1014
State Fair Classes and Contests in Horticulture, 10/14
Trunk Protective Materials, 10/14
Using Annuals in the Landscape, 04/14
Water Conservation Publications, 04/14
Weevils, 08/14
Winter Indoor Plant Care, 11/14
Winter Irrigation, 12/14

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