March 2013 / Volume 72                

In This Issue
March Lawn and Garden Tips
Tree Giveaway at the HGS
Plant Sale Pre-order
Oklahoma Proven Selections for 2013
Ask A Master Gardener...Compost Tea

Weather Stats for Gardeners

Soil Temperature 2" below sod:   

49 degrees 


Rainfall total last 30 days:  

3.47 inches


4 Ways to Contact Us
Email us at:

See our website at: 

Call: 918-746-3701 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.
Understanding Your Soil Test Results
Once you have collected your soil test and gotten the results back, now what? Find out here. 
How to Plant a Tree in Oklahoma Soil
Show and tell.
Cool Season Lawn Care (Fescue)
12-month maintenance calendar.
Warm-Season Lawn Care (Bermuda)
Ditto above.
Trees for Tulsa
A list of 50 recommended trees with descriptions.
Crape Myrtles
A list of over 60, by size and color.
Demonstration Garden
Visit our demonstration garden on 
15th Street, open 7 days a week.  
Oklahoma Proven Plants
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.
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 each year. Register at our office on 15th Street 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.
March Lawn and Garden Tips


  • Cultivate annual flower and vegetable planting beds to destroy winter weeds.
  • Apply mulch to control weeds in beds. Landscape fabric barrier can reduce the amount of mulch but can dry out and prevent water penetration. Thus, organic litter makes the best mulch.
  • Avoid excessive walking and working in the garden when foliage and soils are wet.
  • Start warm-season vegetable transplants indoors.
  • Cool-season vegetables like broccoli, cabbage, carrot, lettuce, onion, peas, spinach, turnips, etc. should be planted by the middle of March.
  • Watch for cutworms that girdle newly planted vegetables during the first few weeks of establishment. Cabbage looper and cabbageworm insects should be monitored and controlled in the garden (EPP-7313). 
  • Continue to plant strawberries, asparagus, and other small fruit crops this month.
  • Start your routine fruit tree spray schedule prior to bud break. (EPP-7319).
  • Remove winter mulch from strawberries in early March (HLA-6214).
  • Remove excessive thatch from warm-season lawns.  Dethatching, if necessary, should precede crabgrass control treatment. (HLA-6604)
  • Broadleaf weeds can easily be controlled in cool-season lawns at this time with post-emergent broadleaf herbicides. (HLA-6421)
  • Preemergent crabgrass control chemicals can still be applied to cool- and warm-season turfgrasses (HLA-6421).  Heed label cautions when using any weed killers near or in the root zone of desirable plantings.
  • March is the second best time of the year to seed cool-season turfgrass; however, fall is the best time to plant. (HLA-6419)
  • Cool-season lawns such as bluegrass, fescue, and ryegrass may be fertilized now with the first application of the season.  Usually, four applications of fertilizer are required per year in March, May, October, and November. (HLA-6420)
  • Begin mowing cool-season grasses at 1 to 3 inches high. (HLA-6420)


  • Prune roses just before growth starts and begin a regular disease spray program as the foliage appears on susceptible varieties. (HLA-6403 & EPP-7607)
  • Divide and replant overcrowded summer and fall blooming perennials. Mow or cut back old liriope and other ornamental grasses before new growth begins.
  • Prune spring flowering plants, if needed, immediately following their bloom period.
  • Plant evergreen shrubs, balled and burlapped, and bare root trees and shrubs.
  • Anthracnose control on sycamore, maple, and oak should begin at bud swell. (EPP-7634).
  • Diplodia Pine Tip blight control on pines begins at bud swell. (EPP-7618)
  • Chemical and physical control of galls (swellings) on stems of trees should begin now. (EPP-7168 & EPP-7306)
  • Dormant oil can still be applied to control mites, galls, overwintering aphids, etc. (EPP-7306)
  • The first generation of Nantucket Pine Tip Moth appears at this time.  Begin pesticide applications in late March. (EPP-7306)
  • Control Eastern tent caterpillars as soon as the critters appear.

Master Gardener Tree Giveaway at the Home and Garden Show  
The Tulsa Master Gardener booth at 2013 HBA Home and Garden Show promises to be one of the best in years. This year the booth has been moved to the center of the lower level of the Expo building. And, as in years past, there will be something for everyone, from little ones to older folks including, as usual, the tree give-away event. Because people have widely differing gardening areas, needs and desires, there will be two varieties of trees given away this year; one that grows rather large and one that can easily be confined to a much smaller area.

For those that have a large space, the Shumard Oak will be available. At maturity, it can reach 80 feet in height and 50 feet in width. Although the oak can be found naturally growing in rich, moist bottomlands, this tree adapts well to poor soil and dry conditions once it is established. It is also well adaptable to alkaline soils common in many area yards. And, like most oaks, it is fairly resistant to pests, but will drop acorns and can be a candidate for either oak decline or hypoxylon canker (no effective control for either). More importantly, it is a fabulous shade tree, very drought tolerant and has stunning fall leaf colors from yellow bronze to a russet red.

For those with space limitations, the Chaste Tree (Vitex), an Oklahoma Proven selection for 2013, will also be available. Its mature size measures 12-20 feet high by 10-20 feet wide. Although it can be grown as a tree, with proper pruning, it can be formed into a shrub due to its multiple trunk form and overall smaller, woody growth. Although it tolerates poor soils, it performs better in well-drained fertile soils and is relatively drought tolerant once established. The tree's attractive and somewhat showy flowers (lavender, pink or white) are formed on the current season's growth, so perform severe pruning while the plant is dormant.

Each day, the first 500 folks who stop by our booth will receive a free seedling. So, come early!

Plant Sale Pre-order for Best Selection  
When? Thursday, April 18th, from 9 am to 7 pm

Where? Tulsa County Fairgrounds, Central Park Hall, Gate 12

With another relatively warm winter mostly behind us and the potential of continued drought ahead, selecting the right plants for your spring and summer garden is very important. Our plant sale website has a list of heat and drought tolerant plants that will still produce vibrant color that doesn't wear out over the summer. Such plants as Mexican heather (cuphea), the profusion series zinnias and salvia mystic spires can produce flowers all summer to attract bees and butterflies. Pre-order now and these plants will be ready to go in your flower beds on April 18th. In addition, you may be interested in trying some native plants that have been around this part of the country for years and thrive in the variable weather patterns we experience. You can also look over selections of Oklahoma Proven and Proven Winners that have been tested and received a stamp of approval. Master Gardeners will be available to answer questions and help you choose plants that will work in your garden. Proceeds from the Spring Plant Sale support the many Tulsa County Master Gardener programs that are provided free in our community.    

Plants may be purchased two ways: 

  • Pre-order Form: NOW is the time to order great bedding plants, hanging baskets, herbs, ornamental grasses and accent plants. This year you can order and pay online through Thursday, March 28. You can also print this form and fill out, or you can pick up a paper order form at the OSU Extension center. The paper forms must be received (by mail or in person) with payment at the Tulsa County Master Gardener office (4116 East 15th St, Tulsa, OK 74112-6198) by 4:00 pm, Thursday, March 28th. IMPORTANT!  Plants must be picked up at Tulsa County Fairgrounds, Central Park Hall between 9:00 am and 7:00 pm on Thursday, April 18th.   
  • Plant Sale on April 18: Didn't pre-order? No problem! You will find a wide variety of plants especially selected just for this one day sale, including natives, proven winners and other hard to find plants. These plants are sold on a first-come, first-serve basis. The sale is open to everyone on April 18 from 9:00 am to 7:00 pm. SHOP EARLY, DON'T MISS THIS! 

To order and pay online or to print a form on your computer and to view pictures and additional information about the plants available on the Spring Plant Sale order form, click here.

Thank you for supporting the Tulsa County Master Gardener Program!

Oklahoma Proven Selections for 2013      
Many gardeners are still feeling the effects of the two-year drought in northeast Oklahoma. The stress on landscape plants has been tremendous, and many gardeners are wondering how to replace the trees, shrubs and other plant materials that did not survive in their landscape, with something more apt to survive what Oklahoma weather can dish out. Each year, the Department of Horticulture and Landscape Architecture at Oklahoma State University, along with expert nurserymen statewide, selects a list of landscape plants  based on appeal to gardeners, disease resistance, and overall tolerance to our weather. The yearly picks include one each of a tree, shrub, perennial, annual, and a bonus category called the "Collectors Choice". These plants have shown they can handle the heat, drought, wind, pests, disease and other elements in our environment if planted according to their needs. They are also required to be non-invasive. Remember that while most are drought tolerant, they will need extra water and care when newly planted until their roots become established. Gardeners are encouraged to look over the Oklahoma Proven.

Here is the list for 2013:

Oklahoma Proven tree for 2013
Winterberry Euonymus (E. bungeana maxim), a small tree or large rounded shrub with pendulous branches, has been selected as the Oklahoma Proven tree selection for 2013.
Euonymus is a genus of flowering plants in the staff vine family and comprises a large number of species of deciduous and evergreen shrubs and small trees. The common name for Euonymus is "spindle" tree. Winterberry Euonymous has showy pink fruits that open to expose reddish seeds and attractive gray bark. It can reach 20 feet in height and 12 feet in width. The small simple ovate to lanceolate leaves are light to medium green in color and turn red-purple in the fall. The tree is adapted to a variety of soil types, has medium moisture requirements, and is cold hardy zone 4-7. Heat tolerance is zone 8. It will take full sun to partial shade. It is relatively disease resistant and drought tolerant once established. Unlike many other Euonymus species, scale insects do not seem to be a problem for this cultivar. It can be used as a patio tree, a border or screen plantings, and as a single specimen and has 'year around' interest in the landscape.

Oklahoma Proven Shrub for 2013
The Chaste Tree (Vitex) is a large shrub with a multi-stemmed trunk, but can be trained into a small tree. Leaves are palmately compound and dark green. The new, improved varieties have large spikes (up to 8"-12" long) of colorful flowers in blue, lavender, pink or white, that are fragrant and make excellent cut flowers. The flowers appear in early summer and continue to bloom sporadically through summer and fall. Vitex is not too picky about soil and is very heat, drought and pest tolerant. This makes it an excellent, easy-to-grow choice for a xeric garden.  Vitex is often considered an excellent replacement for lilacs, which grow much better in colder climates, and it attracts butterflies and hummingbirds. It loves exposure to sun or part shade, likes moist, well-drained soil, and its hardiness spans USDA zones 4-9.

Oklahoma Proven Collectors Choice for 2013
Many of the fruits we enjoy so much don't fit well in today's urban landscapes, especially the standard variety fruit trees. However, today's breeding and production techniques bring us dwarf and miniature versions that fit in just about any space. Thus, the 2013 Oklahoma Proven Collector's Choice includes a specialty fruit collection including miniature peaches, columnar apples, dwarf pomegranate, and dwarf patio-type blueberries. All of these make it easy to enjoy fresh fruit right outside of our backdoors, plus they are ornamental too! They each enjoy exposure to full sun or part shade, and prefer moist, well-drained soil (blueberries require acidic soil down to pH 5). The USDA hardiness zone varies by species, but generally encompasses zones 3-11.

Oklahoma Proven Perennial for 2013
Catmint 'Walker's Low" (Nepeta x faassenii) is an easy to grow, pest free perennial? Try this variety of catmint, which grows 1 to 2 feet high and 1 to 3 feet wide and can be used as edging or in a border, and also works well in containers. Choose a location in full sun to part shade and soil that is well drained. It tolerates dry soil and is deer resistant, and makes a nice addition to an herb or rock garden. Catmint develops into a mound of aromatic, grayish green foliage with spikes of lavender-blue flowers in spring. Pruning off the stem tips after the flowers fade will help keep the plant compact and set another flush of blooms. Plant it alone or in combination with other gray-leaved plants, such as lamb's ears or bearded iris. It grows slowly into clumps which should be divided every three years.

Oklahoma Proven Annual for 2013
Annual - Helenium 'Dakota Gold' (Helenium) is a tough plant and is a native wildflower from Texas and is commonly called "sneezeweed". If you need a touch of gold color, this is the plant to try. It is easy to grow and sports bright golden daisy-like flowers atop finely textured green leaves. These low maintenance annuals thrive in almost all conditions, including drought and hot sun. Dakota Gold grows as low, 6"-8" mounded cushions of fine, dark green foliage covered with golden yellow flowers all summer long. It looks great in containers, in borders and as an accent plant. 

Question: What is "compost tea" used for and how is it made?
Answer: Most gardeners are aware that amending soil with organic material greatly improves soil structure. It improves the soil's ability to absorb and hold water, increases air volume, and adds organic "food" for soil microbes to digest. Healthy soil is full of microscopic life: a single gram of topsoil (about 1/4 tsp.) can contain as many as a billion microorganisms. Many of these microbes, such as Mycorrhizae fungi and Rhizobia bacteria, directly affect the ability of plant roots to take in nutrients from the soil. Because plants require these microbes to survive and thrive, one of our gardening goals should be to grow more microbes!

How can we grow soil microbes? Composting is clearly the best method. Properly composted organic material is full of millions of decay-loving microbes, whose main function is to break down the remains of plants and other organisms. This process releases energy, nutrients, and carbon dioxide - all necessary for plant growth. Unfortunately, most gardeners quickly discover they cannot make compost fast enough to meet their gardening needs. Extra compost must be purchased - an additional expense, not to mention extra labor.

Making compost tea is another microbe-growing option to consider. Compost tea is exactly what it sounds like. Mix compost with water, let it brew until strong, then serve over your plants! A properly made batch of compost tea "grows" the number of microbes found in the original compost. Think of it as concentrated liquid compost. But remember, the quality of the finished tea is directly related to the quality of the compost. If the brewing compost contained harmful disease pathogens, you might inadvertently be growing those along with good microbes.

A simple way to "brew" compost tea is similar to brewing a cup of tea at home. You simply take some compost and place it in some kind of porous material...row cover cloth or cheese cloth  work well, or you can use an old section of pantyhose as a tea bag. Simply fill the bag with compost, then place it in water. Allow mixture to "brew" at temperatures between 59 and 68 degrees for 3 to 21 days. Stir gently several times a day to incorporate oxygen. Without adequate oxygen, the brew may become foul smelling, due to unfriendly bacteria. If it does, add more water and stir more frequently. The mixture should soon balance out (good bacteria vs. bad bacteria), and the smell disappear. Click here for detailed instructions to build a compost brewer.

To apply compost tea to your garden: strain the brew, dilute with water (about 1 part tea to 5 parts water), and spray or sprinkle directly on plants, or use as a soil drench in root zones. Start with weaker tea solutions to avoid "fertilizer burn", then gradually experiment with stronger solutions. Applications are most beneficial once the soil has warmed, during the active growing season. Click here for more information on compost tea.

So next time you're enjoying a nice cup of tea - remember your plants - and brew some tea for them as well!

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