An Important Update On Your Tulsa Master Gardeners
During these unprecedented and challenging times, your Tulsa Master Gardeners have joined others around our community in taking appropriate actions to protect both ourselves and the public from this pandemic. To keep you abreast of our status, the following is a summary of our actions taken to date:

  • The OSU Tulsa County Extension Office building remains closed to all visitors at this time. Although mostly telecommuting, Extension Office staff are slowly returning to work as per Governor Stitt's Phase One Guidelines.
  • All Master Gardener events (Community Events, Speakers Bureau, School Program, Senior Living, Garden Tour, etc.) are postponed until further notice.
  • Soil samples can be left at the Southwest door of the OSU Extension Office in a black lock box. There is a form and a soil bag in a tub on top of the lock box. 
  • While walk-ins to our Diagnostic Center are not available at this time, hotline voice messages are picked up periodically and will be responded to as quickly as possible.
  • MG e-mail traffic is being monitored remotely and will be responded to as quickly as possible.
  • The MG Facebook site is still live and active.

Spring Gardening Tips

 May 2020 / Volume 158
May Horticultural / Garden Tips
Learn about what you should be doing in the month of MAY.  A selection of garden tips (Trees & Shrubs, Turfgrass, Flowers, Water Gardens, and Fruits & Vegetables) can be found by clicking GARDEN TIPS.
For Fruit Tree owners, a couple of handy OSU Fact Sheets on fertilization and maintenance are:

HLA-6259 (Small Fruit Fertilization and Maintenance Schedule)
EPP-7641 (Common Diseases of Stone Fruit Trees & Their Control)
Tulsa Master Gardeners
Video Podcasts

The core mission of the Tulsa Master Gardeners is to provide OSU Extension research-based horticultural information to the local home gardeners and the community.  Given that, we try to reach as many folks as possible through multiple media platforms such as TV, radio, newspaper, magazine, and this e-newsletter. And, as a part of our social media push, we can also be found on Facebook, YouTube and Instagram. To supplement all of these effective ways to communicate, we have now added a new feature - Video Podcasts.  It is called Garden Talk and we invite  you to check it out.

In each episode we talk about a current pest problem, highlight a plant of interest, discuss what we should be doing right now in our lawns and gardens, and answer your questions.

For the latest podcasts, click on:
MG Podcast 014
MG Podcast 014

Hydrangea Tidbits

  • Planting Time: spring or fall - blooms all season long - easy to grow
  • Blooms:
    • On old wood: (Bigleaf/Macrophylia, Oakleaf, Mountain)
    • On new wood (Panicle, Smooth)
    • On both old wood and new wood (Endless Summer, Blushing Bride)
  • Soil: well-watered but well-drained soil, rich/high in nutrients and organic matter, porous - add compost to enrich poor soil
  • Fertilize: Spring
  • Sun: generally prefers morning sunlight and afternoon shade (4-6 hours of sun per day)
    • Full sun: Panicle (most sun tolerant)
    • Sun: Oakleaf, Smooth
    • Sun to partial shade: Endless Summer
    • Part to Full Shade: Bigleaf
  • Prune: avoid heavy pruning - prune only in spring just as new growth appears (don't prune in fall as you may be cutting off next year's blooms)
  • Some Popular Varieties:
    • Big leaf / Macrophylia: Endless Summer, Blushing Bride (Mophead), Pistachio
    • Panicle: Limelight, Little Lime, Quickfire, Bobo, Pinky Winky, Grandiflora
    • Smooth: Annabelle, Incrediball
    • Oakleaf: Pee Wee; Ruby Slippers, Snowflake
  • Color Change (takes a bit of time: 3-6 months)
    • Lower pH (<6.0) = blue blooms - add sulfur @ 2# / 100 sf
    • Higher pH (>7.0) =pink blooms - add lime @ 8-10# / 100 sf
    • Exception: Panicle will not change color (white to pink to red in winter depending on temps)
  • Pests:
    • Adult Rose Chafers and Japanese beetles (prefer Oakleaf)
    • Scale: Oystershell - identified by their clusters of white eggs on stems
    • Slugs: Prefer attacking young hydrangeas
    • Aphids: Small black or green bugs on leaves
    • Deer: prefer other plants more but, when hungry, deer will eat hydrangeas


Most Popular Question: Why won't my hydrangea(s) bloom?
  • Over fertilized: too much nitrogen = more foliage and less blooms
  • Too much shade: need 4-6 hours of sun (but protect from hot afternoon sun)
  • Over pruning: May have removed buds on old wood (don't prune in fall or too early in spring)
  • Temperature: cold winter and/or late freeze will freeze new buds on old wood and will not bloom until following year
  • Time: can take 2-5 years to bloom; pick plants with blooms or bigger specimen
  • Animals: deer may eat the blooms
Pest e-Alert: Swarming Termites

Due to our reasonably warm and continued wet spring, we will probably be faced with an increase in our insect populations.  This is true of both the ant and termite groups or swarms.  If you have a swarm of insects, before applying an insecticide or pesticide, you should identify the type insects causing the problem.   This prevents you from applying the wrong insecticide or pesticide application.

It is very important on determining termite identification due to the amount of damage that can occur if the termites are not properly treated.  To learn more about identifying termites vs other similar insects, such as carpenter ants,  click on TERMITES.
Oak & Other Galls

     {Midge Damage on Pin Oak}              {Gall Wasp Damage on Oak}

                                            {Horned Oak Gall}
Plant galls are formed from abnormal vegetative growth produced by a plant under the influence of an insect, mite, bacterium, fungus, or nematode. Gall formation involves an intimate association between the plant host and gall maker. Galls can be found on any part of the plant, but are most often observed as large, swollen growths on a leaf, on the petiole (stalk that joins the leaf to the stem), twig, or branch.
Gall makers must attack at a particular time in the year to be successful. Otherwise, they may not be able to stimulate the plant to produce the tissue which forms the gall. To find out about that timing and other valuable information about tree galls, including several colorful and interesting pictures of several specimens, cl ick on GALLS.
Rose Disease & Prevention

One of the most gratifying gardening accomplishments can be measured in the successful cultivation of a healthy rose with high quality and abundant flowers. Disease identification and control practices should ensure your plants are given the best chance to thrive. Some of the most prevalent diseases affecting roses in Oklahoma are black spot, powdery mildew, rose rosette disease and crown gall. 

Careful selection of resistant cultivars is the first step in preventing disease, although no cultivar is resistant to all disease. Also, frequent foliage applications of fungicide help deter fungal infections in susceptible cultivars.

For more information  on this subject, consult OSU  Extension Fact Sheet EPP-7607 for a list of  cultivars resistant to fungal diseases, black  spot and powdery mildew and click on ROSE DISEASES for access to this full article on disease AND prevention.
The Curious Case Of The Callery (aka Bradford) Pear

Ah, the beauty of springtime in Oklahoma as the earth awakens from its' winter dormancy. What are those white blossoms on those trees over there? Those trees are the infamous callery pear . . . and we've been invaded. 

The Callery Pear is one of the most common invasive species in the U.S. Brought to the United States over a century ago to help combat fire blight in the pear industry, every spring its' prolific white blossoms are visible along roadsides and many other places. Some have likened the smell of the flowers to rotting fish. It has also managed to encroach into natural and managed forests. Common Callery P cultivars include Bradford, Aristocrat, and Cleveland Select.

Management is difficult and almost impossible to kill. To learn more about these trees and how to eradicate them, click on CALLERY PEAR.

Landscaping With Ornamental Grasses

                                   {Karl Forrester Feather Reed}

               {Little Bluestem}                           {Ivory Feathers Pampas}
One of the most versatile plants you can place in your landscape is an ornamental grass. The myriad shapes, sizes and colors are virtually endless, and their year-round beauty make them a wise choice for your landscape. Determining whether to select perennials or annuals, their watering needs and which are best for our zone is easier than you may think. 

Follow the tips in GRASSES to ensure success in your landscape.
Monarchs & Milkweeds: Spring Migration
Perhaps no butterfly is as iconic as the Monarch. A regal name for an insect that delights both children and adults. We rarely tire of watching Monarchs as they flit among our flowers, feeding on the nectar of favored blooms. 

But, in Oklahoma, Monarchs are infrequent visitors. This is partly because of our location along their migration flyway and partly because of their critically declining population. There are ways we can help their declining population but we need to understand exactly when they need our help. This way we can provide not only what they need but when they need it. 

To better understand this timing issue, let's take a look at their migration and other characteristics by clicking on MONARCHS & MILKWEEDS.
Integrated Pest Management: 
An Environmentally Friendly Alternative To Pest Control

Integrated Pest Management, also known by the acronym IPM, is an environmentally sensitive strategy to prevent, avoid or reduce a pest problem in our lawns, vegetable and flower gardens, trees and shrubs. Knowledge is the key to IPM. Knowing your plants and their common pest problems will help you choose the best methods for your garden. 

Monitor your plants regularly. It is easier to stop pests before they become a problem.

The elements of IPM are good cultural practices, mechanical and physical controls, biological controls, and chemical applications. You can combine methods and determine what works best for your garden.  For a more detailed description of each practice, click on IPM.

The Tulsa Master Gardener Foundation is a 501 (c) (3) organization.  As such, it receives no city, state or federal funding for its Tulsa community outreach programs. In fact, the Tulsa's Master Gardener programs are self-funded by its own fundraisers, from member donations, and from public donations.

The main Tulsa Master Gardener fundraiser is its Annual Spring Plant Sale that is held each April.  Other fundraisers include the Garden Tour and Garage Sale in June.  And, one of the most important income sources that sometimes gets overlooked are the personal and corporate donations.  These are so important in helping us to meet our financial obligations and we want you to know they are very much appreciated. 

MG Endowment Fund
The Tulsa Master Gardeners have been around for over three decades, since 1983.  And, we plan to be around for many more decades. Furthermore,  we are considered one of the top five Master Gardener county programs in the entire nation. We are because of the size of our Foundation membership, the number, diversity and activity level of our various community outreach programs, and our overall financial strength!  
So, we are pleased to announce, in partnership with the Tulsa Community Foundation, the Master Gardener Foundation has established an Endowment Fund to ensure our long-term financial strength. Our plans are to build this fund for many years before making any withdrawals from it. Please consider us as you make your annual gift giving as well as longer-term estate planning decisions. Remember, all donations are fully tax deductible! 
If you wish to make a tax-deductible donation to help fund the long-term success of the program, click on   TULSA MASTER GARDENER ENDOWMENT FUND.
If you wish to make a tax-deductible donation to help fund our annual expenses, click on  TULSA MASTER GARDENER AGENCY FUND.
We thank all of you for having been such faithful contributors both in the past and in advance for your future consideration and participation!  Proud to be a part of the Tulsa area - such a giving community!  

Got a Question? Or Maybe a Soil or Plant Sample?
MG logo
Our Master Gardeners are on hand to assist you with even the toughest gardening questions. Visit us in person, by phone, via email or online! Hours of operation are Monday through Friday 9:00 a.m to 4:00 p.m.

Address: 4116 East 15th Street (Gate 6 at the Fairgrounds)
Phone: (918) 746-3701

Need More Information?
law n fertilizer
complex leaves
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.

Once you have collected your soil test and gotten the results back, now what? Find out here. 

Show and tell.
Cool Season Lawn Care (Fescue)
12-month maintenance calendar.
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.

A list of recommended trees with descriptions. 

A list of over 60, by size and color.

Visit our demonstration garden on  15th Street, open 7 days a week. 

Current and historical source of rainfall, air temperatures, soil temps and much more. Click on Bixby station.  

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