April 2013 / Volume 73                 

In This Issue
April Lawn and Garden Tips
Plant Sale Pickup and Peruse
Get Your Water Garden Ready!
Drips are Good for the Garden
April Showers?
Ask A Master Gardener...Mixed Grass Lawn Care

Weather Stats for Gardeners

Soil Temperature 2" below sod:   

52 degrees 


Rainfall total last 30 days:  

2.22 inches


4 Ways to Contact Us
Email us at:

See our website at: www.tulsamastergardeners.org 

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.
April Lawn and Garden Tips


  • Warm-season veggies to plant this month are most of the beans, tomato, squash, pepper and eggplant. 
  • Diseases which may need control this month include cedar-apple rust in apples and crabapples and fire blight bacterial disease in apples, pears, pyracantha and other members of the rosaceae family. Contact the Master Gardeners for recommendations.
  • Bermuda lawns can be fertilized three to five times per season using one pound of actual nitrogen per 1,000 sq. ft. per application. Apply up to one pound per month April through August for a high quality lawn. Thoroughly water in nitrate fertilizers. Click here for the bermuda maintenance schedule.
  • Fertilize tall fescue lawns with one pound of nitrogen per 1000 sq. ft. this month, if you did not fertilize in March. Click here for the fescue maintenance schedule.
  • Mowing of warm-season lawns can begin now, mowing 1-1/2 to 2 inches tall. Mow tall fescue 2-1/2 inches.
  • See the Ask a Master Gardener article below for care of mixed grass lawns. 



  • Most bedding plants, summer flowering bulbs, and annual flower seeds can be planted after danger of frost has past. This is usually mid-April in most of Oklahoma. Plant warm season annual after the soil warms into the 60's. Visit to www.mesonet.org for soil temperatures.
  • Let spring flowering bulb foliage remain as long as possible in order to replenish energy store in the bulb for next year. These bulbs are best fertilized either in the fall or in spring when tops first emerge using a nitrogen fertilizer labeled for bulbs. 
  • Proper watering of newly planted trees and shrubs often means the difference between success and replacement.
  • Clean out water garden and prepare for season. Divide and re-pot water garden plants and begin feeding fish when water temperatures are over 50 degrees F. See article below for more information. 

Plant Sale Pickup and Peruse   
When? Thursday, April 18th, from 9 am to 7 pm

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

For those of you who have placed pre-orders for our annual Plant Sale fund raiser, the plants will be available for pickup on April 18th.  


If you didn't pre-order, and even if you did, there

will be a wide variety of plants especially available for purchase at 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. SHOP EARLY, DON'T MISS THIS!   
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. Thank you for supporting the Tulsa County Master Gardener Program!

Get Your Water Garden Ready!   
Well, winter is starting to lessen its grip on your lawn, veggie patch, and water garden and everything is starting to "wake up".  So, you're probably ready to get out there and spend some time around your landscape, including your water garden. Remember that spring is a critical time to ensure you have a healthy and enjoyable pond system the rest of the year so, before you "fire up" the water garden for its first use, there are a few things to keep in mind:
  • Pond and Water: If there has been an accumulation of leaves and other debris over the winter, clean the organic matter from the pond bottom with a net or pond vacuum (rotting leaves will raise the water acidity). Start some partial water changes monthly and add a water conditioner. Check the pH, ammonia, phosphorous and nitrate levels. If any of the levels are too high, you should do a partial water change, but do not completely drain and clean your pond as that will actually interfere with algae control and destroy your fragile ecosystem.
  • Equipment:  Check tubing, pumps and filters for obstructions and do a thorough cleaning. Replace UV bulbs, gaskets, and filter material as necessary. Turn on the pump to check that it is running properly and that the pre-filter intake is clean and free from debris. Check for leaks in water lines, streams, pond edges and filter boxes. Turn on UV sterilizer after the biological filter is working properly and the water starts to turn slightly green.  
  • Ecosystem: As you run your pond, add beneficial bacteria and barley straw extract to jump start your pond into a healthy ecosystem as well as to prevent algae bloom. 
  • Fish:  First, fish need a careful inspection in spring following their winter dormancy. Check for any visual stress. Monitor the water temperature and start feeding your fish when the water temperature reaches a constant 50 degrees. Feed a wheat germ-based food until the water temperature reaches 60 degrees at which point you can move to your full-season feeding program. Feed sparingly at first. Also, this is a good time to add medication as a preventative step, the proper amount of salt, as well as products to replenish vitamins and minerals in the water. Remember, the Chloramine in Tulsa's treated water must be removed
    before it is added to aquariums or fish ponds.  
    There are many products commercially available 
    that will remove the chlorine and ammonia
    from water to be used in an aquarium or pond.
  • Pond Plants: Remove any dead plant matter. Divide and re-pot plants as needed.  Fertilize plants to enjoy the maximum amount of growth and bloom in the growing season. Lilies and lotus should be fertilized every 3-4 weeks, marginals every 5-7 weeks. Add floaters (water hyacinth, water lettuce) after the danger of frost has passed (on average, this is mid-April). Add Anacharis to reduce algae growth. 

Once you have taken care of these items and your water garden is tuned up, kick back and enjoy it and marvel that Spring is well on its way. For more information click here

Drips are Good for the Garden       
Looking for an effective way to water your garden? Drip irrigation, also called low pressure or trickle irrigation, has been used in agriculture for many years. It is popular with homeowners because a system is both easy to install and flexible. By placing water at plants roots, it conserves water and reduces the likelihood of disease.

The best way to get started is by obtaining one of several instruction manuals from the companies which manufacture the equipment. There are several good resources, some with video instruction.

Your choice of systems may be simple or complex. The simple way is to connect your outdoor faucet with some fairly inexpensive equipment-a timer, backflow preventer, filter and pressure reducer (these can be bought as "kits"). A faucet adapter with multiple outlets allows you to create more than one line, or zone.

Reduction in water pressure source is essential for the lines and attachments to operate properly. No special tools are needed other than a simple tool to punch holes in the plastic lines.

The distribution line is usually a 1/2 inch pliable polyethylene tube which connects to the faucet attachments. The feeder lines are 1/4 inch soft plastic material connected to the distribution line by an easily installed fitting. Many types of feeder line attachments are available including sprinklers, sprayers and emitters. All are useful, but the emitters are commonly used in gardens.

Emitters are "pressure compensating", delivering a consistent amount of water regardless of the water pressure fluctuations. They are rated to deliver from 1/2 to several gallons per hour. Emitters attached to the smaller 1/4 inch feeder lines are placed at the base of any plant you wish to irrigate. The lines can be very shallow, a few inches if you have to cross a lawn or simply on the  top of the ground covered with mulch in your garden. Another very useful option is to purchase plastic lines with built in emitters.

There are many ways to use drip irrigation. Lines may be run to containers, raised beds, vegetable gardens or circled around tree root zones. Spray heads may be used to cover bed which has too many plants for individual emitters.

Almost without exception, drip irrigation can be adapted to a landscape watering need. All of the parts are easily available at local hardware stores or one of the several specialty irrigation businesses. And the best part is, once you get the system installed, set your timer and let your system do the work for you! Visit our Web site for more information.

April Showers?        
There seems to be a pattern with this drought we remain mired in...a step forward, then two steps back! This is very much how February and March played out this year, as plentiful rain in February gave way to much below normal rain (for most of us) in March. So, where do we stand now?

The good news is...March was cold! On average, March 2013 was about 14 degrees colder than March 2012! Before you say anything, allow me to explain that statement. The reason that we should be glad for chilly weather of late is that the cold temperatures offset the lack of rain; for now at least. The cold has delayed the onset of vegetation "greening up"...think back to last year when the trees had leaves on them by St. Patrick's Day...and has significantly reduced evaporation of soil moisture. Just think how much trouble we would be in with last year's temperatures and this year's rainfall!

Rest assured, warmer weather is coming so this is only temporary, but for the moment, the short term drought effects have been reduced. For long term relief (reservoir and pond levels, deep soil moisture) we still have a long way to go. At this point, the official outlook offers little answer as to what we can expect rainfall-wise through the summer, and shows enhanced probability of above normal temperatures through June (uh-oh). However, the official drought outlook does indicate some improvement expected, mainly because we are heading into the wettest months of the year (remember how well THAT worked out last year?).

What I will offer is the pattern has been active for the first part of April, so perhaps we can make up some ground. But after that it probably becomes a race to summer. We have to replenish the lower soil moisture profiles AND keep demand from plants and the sun/wind satisfied, while re-filling our reservoirs and farm ponds to suit our other needs...and all between now and mid-June or so (no pressure). The good news is there are not large-scale climate indicators saying that can't happen between now and then. The bad news is there aren't any indicators to suggest it is likely to happen. So, think positive...the law of averages has to catch up with us...right?!? For more information visit the monthly and seasonal outlooks on the National Weather Service's Climate Preciction Web site.

lawnQuestion: I have both Bermuda and fescue lawns, but what do I need to do to each and when?

Answer: Lawn care can be confusing, especially when you have a mixture of lawn grass types. A mix of grasses is common because we live in a transition zone between where warm and cool season grasses grow best. The warm season grasses, Bermuda and zoysia, would rather be in central Texas, while the cool season ones, tall fescue and Kentucky blue grass, would prefer Nebraska.

The reason they are called warm or cool season grasses is they grow and perform best during that respective season.

Bermuda and zoysia go dormant (turn brown) in the fall, but begin to green up in March/April and grow best when its hot. These grasses need fertilizer when they are growing - from April (after full green-up) to late August. It is recommended that Bermuda grasses get 2-5 lbs of actual nitrogen fertilizer per 1000 sq ft in divided doses during this growing period. Zoysia needs about half as much per season.

If you intend to either dethatch or aerate Bermuda or zoysia, do it at the start of their growing season. Likewise, if you wish to either seed or lay sod, do it after the ground warms. The best time for this is May and early June. If you wait later, there may not be enough time for roots to be established before winter.

Tall fescue stays green all year, but goes into partial dormancy in the heat of summer and in winter. It grows best in spring and fall before the extremes of temperature develop.

Fescue should receive fertilizer during its active growth periods. Ideally it needs 1 lb of actual nitrogen fertilizer per 1000 sq ft each application, 3-4 times per year. This is best done with 1-2 applications from late February through late April and another two doses in September and again in November. Never fertilize fescue during the summer months, it will make the grass susceptible to heat damage and disease.

Fescue usually does not need dethatching. If aeration is done, it is best to do this from mid September through October.

There is almost always some loss of fescue from the summer heat, necessitating reseeding. This may be done in spring or fall, however, the spring planted grass usually dies in the summer. Fall is far and away the best time to reseed fescue.

For more detailed information go the Master Gardener web site and review the turf section.

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