September 2011 / Volume 55   

In This Issue
Fall Garden Festival
September Gardening Tips
Soil Testing
Spring Bulbs
Growing Garlic
Ask A Master Gardener

Weather Stats for Gardeners

Soil Temperature 2" below sod:   

83 degrees 


Rainfall total last 30 days:  

3.14 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 100, 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.
A Horticultural Happening!  


The 1st Annual Tulsa Master Gardeners Fall Garden Festival - A Horticultural Happening will be held September 17th and 18th! Now that the brutal summer is winding down, thoughts have begun to turn from salvaging what's left of veggie gardens, lawns, shrubs and trees, to recovering and planning for the next growing season. Whether you want to jump into fall gardening, learn what to do with your scorched landscape, reassess your plans for spring gardening, learn tips for plant & tree survival, or simply want to keep the rain that falls for your own benefit, now is the time for planning and doing.


The Fall Garden Festival will appeal to all ages! There will be Vendors, Garden Clubs, Nurseries, Speakers, Classes, Demonstrations, Make & Take Projects, Kids Corner, Plant Swap, Scarecrow Contest with prizes, Garden Shed sale of gently used garden equipment, tools and treasures, and food! The Speaker and Program schedule varies each day and will be posted online. OSU educators along with Master Gardeners will be on hand to share their expertise. Master Gardeners will also showcase the various volunteer programs, and recruit for next year's training class.


Look for the pavilion tents at OCES Tulsa Master Gardeners, 4116 East 15th St., Tulsa OK 74112. Admission and parking are free. Enter at Expo Gate 7 and park in Lot 6. Hours of operation: Sat. Sept. 17 from 9 am-4 pm, and Sun. Sept. 18 from 11 am-4 pm. Visit us online for schedules and guidelines or call 918-746-3701 for more information.  

September Lawn and Garden Tips


  • You have until the middle of September to plant rutabagas, Swiss chard, garlic and turnips and until the end of September to plant cool-season vegetables such as spinach, leaf lettuce and radishes. Click here for more information. 
  • If you haven't had a soil test in several years, this would be a good time to so. See the article below or check the Master Gardeners web site on how best to gather soil sample.


  • Last nitrogen fertilizer should be applied to your warm-season grasses (Bermuda, zoysia) no later than September 15. Don't fertilize if the grass is dormant (brown).
  • Fescue lawns should be fertilized in September after it cools and again in November. Early fall is the best time to establish or over seed a cool-season lawn.


  • After the soil cools, plant or divide peonies, daylilies and other spring blooming perennials. Click here for a list of Perennials for Specific Uses in Oklahoma. 
  • Spring-flowering bulbs will arrive in garden centers and nurseries during September. Select early for best choices. They can be planted in October and November.
  • Fall is also a good time to plant many ornamentals. Watch for specials at your nurseries.
  • Most trees and shrubs planted in the fall will outperform those planted in the spring. Be sure to mulch.
  • Before bringing houseplants indoors, reduce the amount of light they receive by placing them in shade. Inspect for pests, then hose off with water and spray with insecticidal soap or a horticulture oil such as Neem before bringing inside.
  • Plant cool-season annuals like pansies, ornamental cabbage or kale, snapdragons and dusty miller when temperatures begin to cool.
  • Root cuttings from annual bedding plants such as begonias, coleus, geraniums and impatiens. These plants can be overwintered in a sunny window and provide plants for next year's garden.
  • Now is a good time to prepare and plant a new perennial wildflower garden.

SoilTestArticleThe Science of Soil 

Did you know your soil needs certain nutrients in order for plants to grow properly? Did you know that too much of any nutrient is almost as bad as too little? Did you know the soil pH needs to be within a certain range in order for nutrients to be properly absorbed by plants and grasses?


The best way to know what your soil needs is to have it tested. Soil tests provide a scientific basis for evaluating the available plant nutrients in homeowner's lawns and gardens. Properly managing the amount of nutrients added to the soil can save money and protect the environment.


A basic soil test includes pH (the degree of alkalinity or acidity) and core nutrients (Nitrogen, Phosphorus, and Potassium). Soil samples can be taken to the Tulsa OSU Extension Center, and will be sent to OSU for analysis. The cost is $10 and results of the tests generally take two to three weeks to receive.

To ensure you receive an accurate analysis, be sure to correctly obtain your soil sample. Obtain soil from at least 15 locations within the area you want tested, including the top 6 inches of soil from each spot. Place these sub-samples in a plastic bucket, mix thoroughly by hand, and submit a pint of this mixture in a zip-lock bag to the Extension office. Soil samples should be fairly dry and clean of rocks and sticks. Do not sample an area which has received fertilizer within the past two months as this will give a false reading. For more information, click here.

The best time to conduct soil testing is in the fall or early winter so there is plenty of time to correct any nutrient deficiencies, based on the test results, before spring arrives and the growing season begins.

Buy Bulbs Now!  

Flowering bulbs are essential for a beautiful spring garden. It is a good idea to plan your garden and order your bulbs now for best selection. Fall planted bulbs will grow in practically any garden soil, provided they have adequate moisture, sunshine and good drainage. Since growing seasons overlap for different varieties of flowering bulbs, careful planning can lead to a colorful display from early March to May.  


Get Your Money's Worth
In the flower bulb world, bigger is better, so buy the largest bulbs that you can afford. Bulbs are usually measured by their circumference in centimeters. For instance, a top-sized tulip bulb is about 12 cm. Larger tulip bulbs produce superior plants with more impressive flowers. With daffodils, large bulbs will give you 2-3 flower stems in the spring, while smaller bulbs give just one.   


When to Plant

The best time to plant bulbs is when the soil has cooled to about 55 degrees F, usually October or November. Bulbs need cool soil to make roots before the onset of winter. As long as the ground is not frozen, you can still plant bulbs. When planting most bulbs, the rule of thumb is to dig a hole three times as deep as the greatest diameter of the bulb and plant with the growing tip up. It is not necessary to fertilize at planting time as the bulb contains all the food needed for spring bloom.


Where to Plant
Tulips need several hours of direct sun in spring to perform well, and can even be planted under deciduous trees that have not yet formed a leaf canopy. You may choose a bulb that has a shorter mature height if wind is a problem in an exposed area. Tulips look great emerging from a mass of pansies or ground cover, either in a bed or a container. Daffodils need about six hours of direct sun for six weeks after blooming and can be fertilized after blooming to restore food in the bulb for the following year. Let the foliage turn yellow before you cut it and daffodils will come back year after year.   

Tulsa Tulips - Perennial or Annual?

Most Tulsa gardeners treat tulips as annuals, planting them every year. The bulbs you buy are groomed to produce a spectacular display the first year, but the second year may produce only a smattering of blooms and some leaves. You can either pull them out and discard after blooming, or take your chances on a repeat bloom the following year. For more information, click here

Garlic - Easy-to-Grow Bulb for Your Garden

Instead of putting your vegetable garden to sleep for the winter, consider utilizing some of that space to plant garlic. Many online seed suppliers offer a wide selection of gourmet and heirloom varieties not readily found at the local grocery store.  

Choose a site in full sun with loose, well drained soil. When ready to plant, separate the cloves from the head, leaving the outer skin on. Plant individual cloves root end down, pointed end up about 6-8 inches apart. Cover with 2 inches of soil and follow with a thick layer of mulch to conserve moisture and help control weeds. The foliage will start to emerge in about 4-8 weeks. Feed with a fertilizer high in nitrogen monthly during the growing season.

Harvest when the tops begin to die back early the following summer. The garlic will need to "cure" in a shaded, dry, well ventilated area (such as a garage) for about 4-6 weeks before it is ready for consumption. Be sure to reserve some cloves for replanting again in the fall.   


Question: The turf in our Bermuda lawn looks pretty bad.  What can I do now? 

Answer: Bermuda grass might be looking brown and a little thin after our extremely hot summer, especially if water has been limited. As daytime temperatures are expected to gradually cool down and our night temps have already begun to lower a bit, now is a good time to apply a pre-emergent and a final fertilization of the season if you did not do so in August. A pre-emergent is applied to prevent the germination of winter weed seeds in the lawn. Continue to irrigate the turf, especially within twenty-four to forty-eight hours after using a pre-emergent, and immediately water if using a high nitrogen fertilizer to prevent burn. Mowing height is still recommended at 2.5 inches for Bermuda to retain moisture, but you might want to take it down to two inches to apply the fertilizer and pre-emergent. If you mow lower or scalp the turf, it will be brown and more susceptible to the drought conditions. Do not bag your grass clippings and use the mulching blade on your mower to reapply the clippings, as they help hold in moisture and provide valuable nutrients.      

Question: Our beautiful azaleas that made it through the coldest of winters and bloomed this spring are now covered in brown leaves and some green leaves underneath. Should we cut them back or fertilize?

Answer: Many of our trees, shrubs, and perennials are showing signs of stress from the extreme heat with brown leaves. Some of the leaves have turned brown from lack of water, while others are simply scorched from the heat of the sun, turned brown and dropped off. Trees and shrubs will sometimes drop leaves to prevent transpiration or water loss through the stomata, or pores on the lower epidermis of leaves, in extreme drought conditions. If azaleas have been watered regularly and the undersides of leaves do not reveal lace bug damage, there is a great chance that the brown leaves will simply drop off on their own this fall. See lace bug info. Pruning the bushes now will cut off the buds that formed earlier in the summer to become next spring's blooms. If there are any shrubs that you are in doubt about being alive, scratch the stems to find if they are green, or "wick", on their stems. The stems should not crack easily, but should be bendable and supple. It is not a good idea to fertilize now, as it could stimulate new growth that would be susceptible to an early frost or freeze in October. Perennials can be sheared back to promote more blooms before frost. Continue to irrigate all trees, shrubs, perennials and annuals until we receive sufficient amounts of rainfall.        

Question: It seems my cannas are beginning to thrive again and are putting on new orange blooms. However, some new leaves are never unraveling or opening, are full of holes, and turning brown. Is this a sign of under-watering?    


Answer: What you are describing are the symptoms and damage of the canna leaf rollers. There are two different kinds, but the symptoms and control are the same. The adult insect lays eggs inside a new leaf and then the caterpillar stage 'sews' the leaf together with a silken thread that provides a hidden place to eat the leaf.  


The easiest way to stop the destruction is to simply crush the caterpillars inside the leaves after snipping them off from the stem. If there is extensive damage, a further measure to consider is Bacillus thuringiensis (BT), which is sold under various trade names including Dipel, Thuricide, and Bio-Worm Killer. BT is typically applied as a spray, and particular care should be taken to ensure that the underside of the leaves is wet. Do not compost the affected leaves, but discard them in the trash to prevent the spread of the insect from eggs remaining inside the leaf debris. Cannas needing water usually look wilted and will not bloom.


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