Just when you thought you were finished with lawn care for the year, let me remind you about late fall fertilizer applications.
Of course, this only applies if you are growing cool-season turfgrass such as fescue or bluegrass.
Fescue is the most common and best adapted grass for our area. Buffalograss, bermudagrass and zoysiagrass are all warm-season species and are best fertilized in the summer when they are actively growing.
For the rest of us, the November fertilizer application is the second-most important time to give your lawn the nutrients it needs to maintain healthy growth. September was top priority, and if you missed that one, your lawn really needs some attention now.
When selecting fertilizer, look for one that is primarily nitrogen and says it is a quick-release source. There are three numbers on every bag and box of fertilizer that is sold, and the first number in the trio represents the percentage nitrogen. The second and third numbers represent phosphorus and potassium respectively. Many Douglas County soils already contain adequate amounts of phosphorus and potassium.
Plants are unable to tell the difference between organic and inorganic sources of nitrogen, so that choice should be based on personal preference. There are several options of organic and inorganic fertilizers.
That brings up another point — although fertilizers might be labeled for specific plants or specific seasons, those things are really unimportant. Nutrient content and how quickly the nutrients are available to the plant are the most important considerations.
Lawns need about one pound of actual nitrogen per one thousand square feet of lawn. Many fertilizers list spreader settings to allow you to apply this amount without doing the math. In absence of directions from the manufacturer, calculations are necessary. Look for something like a 25-4-4 fertilizer.
Since 25 is the first number, it means this fertilizer is 25 percent nitrogen. Four pounds of 25-4-4 is needed to get one pound of actual nitrogen. For a 21-0-0 fertilizer, a little less than five pounds is needed to equal one pound of actual nitrogen.
Sweep up any fertilizer that lands on the sidewalk, street, driveway, or any other hard surface. Toss the fertilizer back onto the lawn. Excess fertilizer left on hard surfaces can wash into storm drains and ditches and enter our water supply.
Applying fertilizer now allows grass plants to store carbohydrates. Lawns that are fertilized appropriately in late fall turn green more quickly in the spring and maintain healthier growth throughout the spring.
Spring fertilizer applications often lead to excessive shoot growth (more mowing), and the nutrients are more likely to be lost in frequent spring rains. In research trials, turf fertilized in the fall exhibited better winter hardiness, root growth, and shoot density than turf fertilized in the spring.
Why fertilize turfgrass at all? There are a few reasons:
Fine, fibrous turf roots help to minimize soil erosion from your lawn. Plants with taproots such as dandelions and plantain, and plants with shallow root systems like crabgrass are less effective at holding soil in place.
Turf acts as a filter to stormwater runoff and traps dust and dirt particles from the air.
Turf grows slower than many grassy weeds (crabgrass comes to mind).
Fall fertilization is just one step to having a healthy, erosion-preventing stand of grass. Next year, try mowing grass at the highest setting on the mower and returning the clippings to the lawn. Both of these practices help grass plants establish better root systems and reduce the need for water and nutrients.