Nitrogen (N) is what we call a primary nutrient in the turf world. This means that along with the other two primary nutrients, phosphorus (P) and potassium (K), it is the soil nutrient most needed for good turf health and growth. Every bag of fertilizer will have three numbers on it, such as 10-20-10, which tells the percentage of each nutrient in the bag. For example, a 50 lb. bag of 10-20-10 granular fertilizer will be 10% N (5 lbs), 20% P (10 lbs), and 10% K (5 lbs). For most purposes, while this is a common fertilizer, it’s not good for turf, as it has way too much phosphorus and not enough nitrogen. The only time this would be a good fertilizer to use is during the seeding process, where more phosphorus is needed, or if the soil is deficient in phosphorus, which in the Tulsa are is rare. There is usually plenty of phosphorus in the soil, and it does not leach much, therefore we don’t use much at LawnAmerica. Excessive levels of P can also lead to algae growth in nearby lakes and streams, so another reason we limit the use of it.
At LawnAmerica, we are using a fertilizer blend of 36-0-5 right now as spring is coming on. The nitrogen is the key right now, so that’s the main ingredient in our blend. The last number, potassium, is also often found in adequate amounts in the soil, but turf health will improve with good and even high amounts. It is not utilized by the grass nearly as much as nitrogen is, and it stays in the topsoil longer than nitrogen, so the amounts we apply are less. The fall fertilizer will have a higher level of potassium, as the bermudagrass is starting to go into winter dormancy.
Nitrogen is the key ingredient. It’s what makes the grass grow and turn the deep green color turfgrass managers and customers desire. And there are many different types of nitrogen, with different release rates and quality. This is where LawnAmerica fertilizer is unique, and superior to others. As bermudagrass and zoysiagrass are starting to come out of winter dormancy, some N will help, but one does not want to just dump a lot of quick-release nitrogen on at once, as that is bad for the root system and cause excessive topgrowth. Nitrogen is either utilized by the turf, will leach through the topsoil, or be lost into the air basically over a period of 4-7 weeks, depending upon a myriad of factors. Adding slow-release nitrogen components to a fertilizer blend helps even out the nitrogen release and extends the release and therefore the green color up to 7-12 weeks in most cases.
Of the 36% nitrogen in our spring blend, or 18 pounds of actual N, 70-80% of it is slow-release nitrogen, a blend of Uflexx, Umaxx, and XCU coated urea. This allows us to safely apply a higher amount of fertilizer now, and lead to a longer and more consistent turf response and green color. This bag also costs me about 40% more than the bag of fertilizer that many competitors are putting out now, as slow-release nitrogen is more expensive than just applying straight Urea (46-0-0) for example. But one gets what they pay for generally, so the higher fertilizer cost for me is justified with a better performing turf, and happier customers.
All fertilizers are not created equally, nor will they perform equally. A great-looking lawn will not happen without good fertilization. And the best defense against spring weeds is a thick, healthy turf, which good fertilization helps provide. So if you’ve not fertilized yet this spring, this weekend would be a great time to do so, or just call the pros at LawnAmerica, where we do it right!