newsletter logo1        
April, 2010                                                                 Number 36 
Soil temperature at April 4:  65 degrees                                  Rainfall past 14 days:   1.88 inches
Ask a Master Gardener
I was told that it is a good idea to sterilize my birdfeeders.   Is this necessary?  It is a good idea to give bird feeders a good cleaning in the spring or more frequently, if needed.  Using a plastic pail or container, submerge the feeder in a solution of one-to-ten parts bleach and water for ten minutes.   Sometimes a brush is needed to remove debris.  Most feeders can be disassembled to reach encrusted seeds on the bottom.  Rinse and air dry before refilling with seed.  Some bird species, like the HousebirdsFinches, can develop an eye disease that may cause blindness contracted from fungus or bacteria on dirty feeders.  Clean feeders will ensure no diseases are being carried back to the young in the nests.         


I read that a "themed" garden can be fun.  I would like to have a color theme, how do I begin?  Themed gardens can be interesting to plan and make quite the statement.  Begin by choosing plants of the same color or opposites on the color wheel.  An all blue garden can be very soothing, or all white blooms that can be seen at night are very popular.  Colors like yellow and purple are very striking to the observer.  Choose plants that have the same light requirements and be careful to observe throughout the day the number of hours of sun that the plants will receive.  If you plan to hand water the area then water requirements do not need to be similar, as in areas that are irrigated in the same zone of a sprinkler system.  Use groupings of the same cultivar for more impact instead of single specimens.  Consider that oranges, yellows, and reds attract butterflies and hummingbirds in sunny areas and a larger patch of these colors can be seen more easily.  A particular design pattern can be achieved by spacing individual plants closer together, or perhaps forming a family initial.  Master Gardeners will have perennials for sale at our annual Plant Sale on April 15 at the Central Park Hall on the Fairgrounds from 10AM till 7PM, and will be able to assist you in your selections. 
I have a very wet spot next to my backyard gate that just needs something!  Will any plants tolerate the standing water and full afternoon sun?  Most of the ornamental grasses and sedges that range from three feet to six feet tall prefer wet locations.  A different look, next to the garden gate, might be to utilize a Yaupon Holly.  And remember Cannas, that come in a wide range of colors of blooms and variegated leaves also tolerate wet areas and are even grown in containers in backyard ponds.  Note that water standing for more than several hours may cause problems for any plant due to lack of oxygen in the soil area.  
My tree rose is leafing out and the leaves on the bottom of the plant are different from the ones on the top!  It is planted in a container and I wonder that is affecting the leaves?  Rose trees are usually grown on a graft from a different kind of rose, and thus the different leaves.  Remember that newly emerging leaves sometimes look different, so wait until the leaves are full size.  If the newly rosesemerging leaves are indeed different, then simply prune them off to keep the look of the rose that you purchased.   Container grown roses can do well if the container is large enough to support the plant and provide enough winter insulation to prevent roots from freezing.   Remember that container grown plants require more frequent watering and fertilizing since the plant cannot draw nutrients or moisture from the surrounding soil.
Mark Your Calendar 

Tuesday Evening Gardening Classes start April 6 at the Extension Center on 15th Street.  Free.  5:30 to 6:00. See next column for dates and topics. 

Plant Pick Up. If you ordered bedding plants from the Master Gardeners, pick up date is Thursday, April 15 from 10:00 a.m. to 7:00 p.m. at Central Park Hall at the Fairgrounds. 
Showcase Garden Tour of six MG gardens, June 26 and 27.
Need more information?  Click on any of the links below
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.
Trade names and where to find them   
How to Plant a Tree in Oklahoma Soil
Show and tell.
Landscaping and Gardening for Butterflies
How to attract butterflies to your garden 
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 2010.  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. 
4 Ways to Contact Us 
Email us at:
See our website at:
Call us at: 746-3701 from 9-4,
Visit us at 4116 East 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.
Forward to a friend
If you would like to forward this issue of our eNewsletter to a friend, just click the "forward email" at the bottom of the page.
April Lawn and Garden Tips
Free Tuesday evening gardening classes start this week.  See below for the topics.

         April 15 is usually a safe date to start planting bedding plants and annual seeds.

         Plant summer flowering bulbs such as Dahlias, cannas and elephant ears when soil temperature has warmed to 60 degrees.  Caladium bulbs need warmer soil, up to 70 degrees. The soil temperature at the Bixby station on April 4 was 65 degrees.

         You can fertilize roses now.  Use a recommended rose formula fertilizer.

          Mulch trees and shrubs now.  Recent research shows that newly planted trees that are mulched grow up to three times faster in their early years. Wait until soil warms before mulching garden beds.

         Prune out winter damaged limbs and plants.  Prune spring flowering plants like Azaleas and forsythia, after blooming.

         This is the second best time to over seed your fescue lawn.  (Last fall would have been the best time.)  Don't over seed if you have applied preemergent this year.

         Fertilize your cool season lawns, tall fescue and bluegrass, once in March or April.  Don't fertilize again until September and November.

         Fertilize Bermuda lawns only after fully green, usually late April.  Bermuda needs a total of 3 to 5 lbs of nitrogen per 1000 sq feet yearly, in divided applications, April thru August.

          Let spring flowering bulb foliage remain as long as possible before removing it.

         Ruby Throated hummingbirds arrive from Central and South American this month.  Put out sugar water, one part sugar to four parts water.  A red dye is not needed.

         You can visit with Master Gardeners at most Tulsa nurseries on Saturday and Sunday, April 24 & 25 during Ask a Master Gardener Week.


Reminder:  If you ordered plants last month from the Master Gardeners, pick up date is Thusday, April 15 at the Central Park Hall at the Fairgrounds, from 10:00 a.m. to 7:00 p.m.
Free Tuesday Evening Gardening Classes

Our popular classes are held every Tuesday evening in April and May at the OSU County Extension Offices, 4116 E. 15 Street (gate 6 at the fairgrounds).  Classes begin at 5:30 and last for 30 minutes, however, we will stay to answer questions for as long as needed.  There is no cost and no pre-registration.  Stop on your way home from work.


April 6 - Soil Fertility & Lawn Maintenance

April 13 - Vegetable Gardening

April 20 - New Perennials

April 27 - New Annuals

May 4 - Ground Covers for Tulsa

May 11 - Drip Irrigation

May 18 - Landscaping for Low Maintenance

May 25 - The Plants of OSU Demonstration Garden

Oklahoma Proven 2010


The Oklahoma Prove Selections for 2010 include a perennial and an annual.  The perennial is the Toad Lily and the annual is the Silver Falls Dichondra. Both are very unique plants and an attractive asset to your garden.


Toad Lily Tricyrtis hirta

This plant is a very easy plant to grow in shade and partial shade.   They like the shade and are an understory plant, therefore making them a great plant for woodland gardens.  They grow best in moist soils and can even be tolerate of wet conditions.  TheyTOAD LILY grow 2' to 3' tall and about 2' wide.   Since the blossoms are small it is best to plant them close to walk-ways and patios.  This makes for better observation of the unique flower.   There are several different colors of this flower now available for planting.  Exposure: Shade to Partial Shade.  Soil: Moist, well-drained.  Hardiness: USDA Zone 4-8 Tulsa is 6+ to 7.


Silver Falls Dichondra Dichondra argentea 

This annual is a low growing ground cover that will reach about 2" in height and 3"-4" width.   Because it is a native dichondra  species from southern Texas and Mexico it is very drought resistant and heat tolerant.  It is an   excellent plant for use as a ground cover.   It is also great to use in hanging baskets,SILVER FALLS potted or container displays or in rock gardens. Any use that will display their long trailing branches is suggested and since they are very showy, their placement around patios, ponds and waterfalls can provide a beautiful setting in your garden.  Exposure: Sun to Partial Shade.  Soil: Well Drained.  Hardiness: Use as an Annual.  


Click here for the complete list, pictures and descriptions of the Oklahoma Proven selections for 2010, as well as for prior years.

Controlling Insects in Your Vegetable Garden


Insect and disease control in your vegetable garden should being with prevention.  Start by buying plants which have genetic resistance to pests and disease.  Also, practice sanitation and remove last year's plant trash and all of this year's weeds from the garden site.  Both may harbor insects and disease.

Physical barriers can keep insects out of your vegetables.  A barrier may be something as simple as paper collars around the stems of transplants to prevent cutworms or sheets of porous plastic, called row covers, to cover veggies at risk.

Vegetable gardens need frequent inspections and are best done daily.  Large insects and caterpillars may be removed by hand during these times. Aphids, spider mites, whiteflies and other pests can be removed by a sharp stream of water from the garden hose.

In spite of best efforts, often a pesticide - organic or conventional - will be needed for control of insects and mites.  When selecting one, it absolutely must be labeled for use on vegetables.  It is confusing that anfall vegetables insecticide may come in both a spray for vegetables and one for flowers.  Even though the insecticides are the same, other contents of the spray for flowers may be harmful if used on vegetables and consumed.  Labels will also list the safe time interval between spraying and harvest; this is different on each chemical and must be heeded.

If a spray is needed, consider starting with organic botanicals.  When used correctly, they are effective, safer for you to and for the good insects.  However, most have a short duration and need frequent application.  Included in this group is "Bt," or Bacillus thuringiensis, a bacterium effective against most veggie caterpillars, but safe for people and pets.  Aphids, spider mites and other soft-bodied pests can be treated with both insecticidal soaps and horticultural oils.  Neem oil and neem extracts are good oil selections.  Pyrethrum is a short acting organic insecticide, obtained from the Chrysanthemum flower, useful for control of several insects, including beetles and squash bugs.

Finally there are several effective chemical insecticides labeled for vegetables.  These include Malathion, Seven, cyfluthrin and others.  They kill a variety of insects, including the beneficial ones.  These should be used after other options are exhausted.  Always read and observe label directions carefully.

Extension Logo  tulsa county logo