Yellowish Turf — Should I Apply Fertilizer Now?

Consider using a little fertilizer now.

This year a lot of the fertilizer you applied in the fall has been used by the grass plants.   If your field is yellowish and weak it would be a good idea to encourage it a little so it will be better able to respond to the normal fertilizer you apply later in March.  The fertilizer ammonium sulfate is good for an early send off.  We would not recommend it a rate of more than 5 lbs./ 1000 square feet.  It would be better to apply it just prior to a rain.  If the fertilizer is left on the turf without some precipitation on the way you may get a foliar burn.



The soil test is one of the best money savings tools that is available to those involved in managing turf grass sports fields. All of us who are involved in maintaining turf grass sports fields are well aware of the necessity of fertilizer. Unfortunately, this is often the weakest link in the maintenance program. In many cases, quantity is often mistaken for choosing the right nutrients to get the best result for the amount applied. If the proper balance of nutrients is not available to the grass plant – it will not have a fighting chance of surviving the tremendous traffic demands. Furthermore, a person may be applying fertilizer that has only limited uptake by the plant because the soil may be too acetic or basic. The soil test will show the soil ph often an application of lime to correct the soil ph will save you an additional application of fertilizer. Ideally, a ph ranging from 6.2-6.4 seems the best range of microbial health and nutrient availability.

Soil testing

It is wise to use the same laboratory every time you make a soil test. The data is easier to compare if it is in the same form year after year. The initial soil test that you take will be the benchmark from where you assess your progress. Lastly, when taking the samples to be tested it is important that you keep the depth to the effective root zone of the plant. This is usually no deeper than 4″. The sample you submit should contain soil from at least 5 places across the field.

If you would like to further discuss these comments, please give us a call
@ 503-692-1195, and ask for Dick @ ext 2 or Damon @ext 6.

Is It Too Early to Fertilize my ” Yellow /Hungry Field ?

This winter has been exceptionally wet. February alone has recorded 10 plus inches in the rain gauge. The warm/cold cycle continues. The soil temperatures are cold and applying normal analysis fertilizers will be a waste of money until the fourth week in March when the Spring Solstice arrives. The night lengths begin to shrink and the days become longer and as a result the soil temperatures begin to rise more rapidly. When the soil temperatures reach approximately 53 degrees the plants begin to take up soil nutrients more efficiently. So now with the cold temperature what can we do? The old standby fertilizer ammonium sulfate is a very useful tool. This material will release a little nitrogen every time the soil temperature in the top inch raises – as with a sunny day. Consequently, the grass plants have a little nutrient immediately available to them. The rate to apply is no more than 5 lbs. of product per 1000 sqft. Make this application when there is the possibility of rain otherwise you may get a temporary burn. If this product is used later in the season it may give you a strong flush of growth which will produce more grass clippings than you want to deal with. But now the timing is excellent. Later in March when you apply the balanced fertilizer – it will do even better because a healthy grass plant can better utilize the fertilizer.

Are we “Aquatic” Turf Grass Managers?

This is a realistic question considering the 15 plus inches of rain most of Western Oregon and Western Washington has received in December along with what is occurring in January. Most of the turf will survive this unless it has been totally suffocated. Unfortunately the grass best suited to recover quickly will be the annual bluegrass poa annua. It does better with wet feet than most others. What can we do to encourage the other turf when things return to normal? If you have not done so consider testing your soil. The best balance of nutrients and particularly the soil ph (for acidity) is your best offense. If the ph is below 6.2 consider a lime application. Pelletized lime should not be applied at more than 50 LBS/1000 sqft in any one application because it will cake on the turf – and by all means do it during the rainy season to encourage immediate action. When the soil ph is in the 6.2- 6.4 range two things are occurring: there is maximum microbial activity taking place in the soil and a majority of the nutrients are most readily available to the plants. Later in the spring continue with your normal cultural practices –particularly the aeration to encourage more air into the root zone.

Mild January and “Mother Nature” has jump started the grass plants.

The mild January has got things growing more than normal here in Western Oregon. Many sports fields are yellowing enough to draw concern. The soil temperatures have warmed to in the top ¾” to the point where the roots are actively taking up nutrients. It is still too early to consider applying a complete fertilizer but supplying the plant with a little nitrogen at this time will be beneficial and return the color. Applying ammonium sulfate at no more than 5 lbs/1000 sqft. will help bring this color back. You must be careful not to use this fertilizer if there is no rain in sight because you may get a foliar burn. The application of the nitrogen at this time will also help your turf grass out grow any damage done from the turf disease “Red Thread”.

Winter seeding turf blends

Last year I made reference to the colder temperature germinating ryegrass varieties and how effective they were. I am going to put further emphasis on this fact. We are watching some of these varieties germinate well into December. If you were to go on the belief that October 15th was the cutoff date for seeding you would be missing out on one very effective tool in the field manager’s arsenal. Seed is relatively inexpensive and to let bare areas in your field remain so all winter, without trying to encourage turf cover, will no doubt give you a stand of annual bluegrass – which is going backwards. So call your seed resource person and have them bring you up to speed on these cooler temperature germinating ryegrasses. The only drawback to seeding in the monsoon season is “not” rotting seed but seed going “down-stream”. It is for this reason that you want any seeding that is done to be pushed into the soil. Let the players do this with their cleats or again find a way to press it into the soil. I am well aware the freezing cold can damage some of the newly germinated seeds but surprising enough we still see good results when it thaws in the spring. You will be pleasantly encouraged with the results.