March 2015 / Volume 96         

In This Issue

Weather Stats for Gardeners

Soil Temperature 2" below sod:   

54 degrees 


Rainfall total last 30 days:  

2.63 inches


Donations Keep Tulsa Master Gardener Program Strong
The Tulsa Master Gardener Foundation receives no city, state or federal funding for its programs. The majority of Tulsa's Master Gardener programs are self-funded. While we have many dues-paying members, income received from dues is less than 5% of annual expenses.

Tulsa Master Gardener's own fundraisers make up most of the income for expenses. A significant portion comes from the Tulsa Master Gardener annual plant sale that is held each April. Other fundraisers include the Garden Tour (June) and "garage sales" that occur from time to time. However, one other income source that sometimes gets overlooked is  personal donations.

To find out how you can help support all that the Tulsa Master Gardeners do for their community, contact the Tulsa Master Gardener office directly.

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

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 recommended trees with descriptions.
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 & Garden Tips
  • Cultivate annual flower and vegetable planting beds to destroy winter weeds.
  • Avoid excessive walking and working in the garden when foliage and soils are wet.
  • Start warm-season vegetable transplants indoors.
  • Your 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.
  • Pre-emergent crabgrass control chemicals can still be applied to cool- and warm-season turfgrasses. 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)
  • 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.
  • 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.
  • 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 they appear.

Tulsa Master Gardeners Spring Plant Sale!     
The Master Gardener program is dedicated to educating and assisting the public in the care and maintenance of flowers, turf, trees and shrubs and the use of insecticides, herbicides and other pest control issues. Our annual Spring plant sale supports this effort by offering great looking plants selected by Master Gardeners for your spring gardens. We are offering a wide selection of bedding plants, interesting choices for containers, perennials, grasses, herbs and tomatoes. The deadline for pre-ordering your plants is Friday, March 27.

To view picture of the plants available, please visit our website ( Orders may be placed through our web site using a credit card through PayPal. A printable form is available on our web site, or can be picked up at the Extension Center at 4116 E. 15th St., Tulsa, OK  74104 (Gate 6 at the fairgrounds). A team of Master Gardeners will be available from 10 am to 4 pm from March 23 to March 27 at the Extension Center to accept your orders and offer credit card payment at that time. All of our plant prices include sales tax.  

The plants will be ready for pick up at Central Park Hall on the Fairgrounds on April 16, after the last average freeze date for Tulsa. We also bring in many unique and special plants for our one day sale on April 16. We have many native plants for sale and will offer milkweed, the larval plant for monarch butterflies. The sale is very popular so come early for the best selection. 

Thanks for Visiting Us at This Year's
HBA Home and Garden Show!     
The HBA Home and Garden Show is one of the most challenging feats for the Master Gardeners to pull off while accomplishing extensive outreach to the community. With a few months of planning and a short setup window, the MGs always transform an empty concrete slab into an oasis of lush greens and vibrant blossoms. Thousands of visitors flock to our space in 'The Gardens' to see and learn about gardening techniques or just enjoy our layout.

Our visitors look forward to returning each year to acquire fact sheets on a huge variety of gardening research, trends and techniques, and to stroll through our landscaped beds to get ideas and motivation for their own spaces. Tulsa MGs are also available for any specific questions one might have.  

This year our space included an Asian inspired garden, wildlife habitat, winter interest, spring and shade landscape areas. Gardening techniques displayed this year included square foot gardening, hydroponics, a keyhole garden structure and small indoor and outdoor tabletop gardens. Our children's activities are centered on the life cycle of plants.

If you missed us this year, come and visit our Extension office for more information on any of these techniques. See you again next year!

Lasagna Gardening, Mama Mia!   
Lasagna gardening may be just what you have been looking for! It's easy, economical, and a good way to recycle. And you'll never have to bag leaves again!

You can start a lasagna garden at any time. It's also known as sheet mulching, no-till gardening, or sheet composting. Watering and weeding are reduced through the heavy layers of mulch. Lasagna layering builds soils that are chock full of nutrients.

You are not limited to square beds, because you can form landscaped beds, making them into any shape.  The process also works in containers.

Recipe Ingredients and Instructions for Lasagna Beds:
The basic idea for developing an lasagna garden is to apply alternate layers of green and brown materials.  It's okay, but not necessary, to mix in soil. Decomposition is faster if you chop up larger materials such as leaves, twigs, wood, and newspaper into small pieces.

The green, or nitrogen layer, is composed of "live" or food-based goodies: e.g. grass clippings or other green plant material, pea or bean vines, peelings, fruit and vegetable scraps, used coffee and tea grounds, egg shells, and certain types of animal manure. Pet manure is not acceptable due to harmful bacteria, but it is perfectly fine to use "good" manure dispensed by poultry or by plant-eating livestock such as cows, sheep or  llamas. Composted manure is also available at most garden centers. Avoid animal meats, bones, oils, and fats which introduce unwanted bacteria and invite foraging animals.

The brow, or carbon layer, consists of dry, dead goodies: e.g. dry leaves, straw, hay, newspaper, worm castings, cardboard, small twigs, wood chips. If you can, avoid cedar, pine, walnut. They have chemicals that retard plant growth.

You should try to achieve a carbon to nitrogen ratio of  2 to 1. For every 2" layer of carbon goodies you apply, apply 1" of nitrogen goodies. Adding more greens than browns causes it to heat up too fast and  become acidic and overloaded with carbon dioxide.

To build your beds, just follow these simple steps:
  1. Lay down 7-10 newspaper sheets or one thickness of cardboard to cover desired area...there is no need to dig up existing grass. Overlap the edges by 4"-5". Water down the paper or cardboard to set it in place.  Avoid full-color newspaper, which may contain harmful inks.  
  2. Apply a 2- 3" thick layer of GREEN nitrogen material.
  3. Next apply 4"-6" of BROWN carbon-rich material.
  4. For subsequent layers, add another layer of nitrogen, followed by carbon items. When done, the stack of layers will be 1 to 3 feet tall, but they will shrink as the materials decompose.
  5. Apply a final layer of about 2 inches of weed/seed-free organic matter, such as straw, fine bark, or dry leaves, then water thoroughly. For the first 2 weeks you may cover with plastic cover to accelerate decomposition. You can mix the layers together by turning them as they decompose, but they will break down even if you do nothing. Keep the bed moist to activate decomposition and attract worms.
  6. Time to plant!  You will be successful growing in lasagna beds if you plant right away. The beds planted next year will be even better because then your soil should be just right!
If the new bed will have a few months to decompose before planting, you can substitute manure or several inches of compostable material for the last layer. When you do plant, a layer of compost will be needed to act as a seed bed.

To plant seeds and plants, push top layer aside to reach the compost/soil layer right below. Buon appetito!

Pruning and Care of Roses!   
Roses have always been and continue to be one of the most popular flowers in Oklahoma. Although some roses are considered high maintenance landscape plants, several new varieties and species exist that are carefree, easy to grow, and look beautiful in the landscape. Proper pruning will help to get your roses off to a good start in the spring.

Pruning: Almost all roses need some form of pruning. Spring is the best time to prune all varieties, except those that bloom in the spring, such as climbing roses (prune those after flowering). Prune after the threat of the last hard freeze (below 28 degrees) is behind us, usually by mid to late March. Because pruning stimulates new growth, pruning too early may cause the new growth to be susceptible to damage by late cold snaps. The objective of pruning bush roses is to remove dead and damaged canes, improve its overall shape, and enhance air circulation by opening up the center of the plant. Pruning can also affect the numbers and sizes of blossoms. Prune moderately for more and average-sized blooms; prune more heavily for fewer, but larger, flowers.

Site Selection: Plant in an open, sunny location protected from strong winds. Plants should have at least six hours of full sun. To avoid reflected heat and sunburn, plant at least two feet away from any wall. Avoid planting under trees where they may suffer from a lack of sunlight and competition with tree roots.

Site Preparation:  Like most plants, roses like a well-drained location rich in organic matter. Soils for roses should be slightly acidic, around 6.0 pH. A soil test is recommended before adding any amenities. As needed and as per the soil test, add sulfur to lower the pH or add hydrated lime to raise the pH.  

Plant Selection: Before purchasing rose plants, analyze your garden or yard to determine what size, type, and color would be most pleasing. Consider your own interests and gardening ability. There are a seemingly endless number of varieties available these days, so visit your local garden center for additional advice.

Fertilization: Fertilize roses with organic or slow-release balanced fertilizer at pruning time, or up to 4-6 weeks after spring planting. Apply a complete fertilizer or special rose fertilizer, as too much nitrogen will decrease blooming. Always follow label directions. Work the fertilizer shallowly into the soil and around the plant, keeping it away from the stems. Additional application may be made every 4-6 weeks during the growing season. Final fertilization should occur around mid-August, as excess nitrogen produces new soft growth that could be susceptible to winter kill.  

Disease Control: Both cultural and chemical controls are recommended to control diseases. Some common cultural control measures that will greatly help include: purchase disease-resistant cultivars, avoid overhead watering, water early in the day so the plant dries out before dark, plant with good ventilation, remove and destroy infected leaves and canes, and mulch soil around plants. The most common diseases are black spot and powdery mildew, although the virus Rose Rosette is becoming increasingly problematic in our state (see OSU Fact Sheet EPP-7329 for more information). Spray early and often with recommended fungicides.

Roses are forgiving and a little pruning with good clippers and thick gloves will be repaid with the sight and smell of summer blossoms that are unique only to roses. For more information on rose care, refer to OSU Fact Sheet HLA-6403 (Roses in Oklahoma) for rose maintenance and EPP-7607 (Diseases of Roses) for rose disease identification and control.