Beautiful lawns và gardens start with healthy, well-nourished plants. From grasses khổng lồ flowering shrubs, every plant"s need is different, but some basics apply across the board. Choosing the right fertilizers for your lawn & garden doesn"t have to be difficult. Armed with fertilizer basics, making the right choice is as simple as 1-2-3:

What the Numbers Mean

All fertilizer products must provide some uniform information to help consumers compare products easily. Every label carries three conspicuous numbers, usually right above or below the product name. These three numbers khung what is called the fertilizer"s N-P-K ratio — the proportion of three plant nutrients in order: nitrogen (N), phosphorus (P) & potassium (K).

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The product"s N-P-K numbers reflect each nutrient"s percentage by weight. For example, the label on a 12-pound bag of Ultragreen Lawn Fertilizer 30-0-4reveals that it contains 30 percent nitrogen, 0 percent phosphorus & 4 percent potassium, in addition to its other beneficial ingredients. This comes in handy when soil test results recommend pounds of actual nitrogen rather than specific fertilizers. By multiplying 12 pounds by .30, you"ll see that this 12-pound bag contains slightly more than 3.6 pounds of actual nitrogen.


Why These Three?

Plants need larger quantities of nitrogen, phosphorus và potassium than any other plant nutrients. Often called primary macronutrients, these three are among the 17 nutrients essential khổng lồ all plant life. Other elements, such as iron, are just as critical khổng lồ plant survival, but plants need them in much smaller quantities. Additionally, different plants have different needs. Azaleas, for example, need more iron than many other plants, so specialty fertilizers, such as UltraGreen Azalea, Camellia & Rhododendron Plant Food 10-8-6is formulated with iron, magnesium và 3 chelated essential plant nutrients for plant vigor & beautiful blooms.This amount of iron is shown in the ingredient panel of the sản phẩm label, but not in the N-P-K ratio.

Plants derive all their essential nutrients naturally from air & soil, but soil can get depleted, especially in thriving lawns và gardens. Because plants use larger amounts of N-P-K, these nutrients need frequent replenishing. Other factors enter in, too. Nitrogen moves freely in soil, so water from heavy rains or irrigation steals nitrogen away in a process called leaching. Fertilizer products step in & replenish used và lost nutrients so that lawns & gardens stay nourished.


How N-P-K Affects Plants

Each of the three nutrients in the N-P-K has its own special job lớn do. Nitrogen (N) spurs vigorous, leafy growth và rich green color in lawn grasses & other plants. Without enough nitrogen, growth slows & lawns & plants turn pale. With too much nitrogen, flowering and fruit-bearing plants put their efforts into green growth & forfeit their blooms and fruit.

Phosphorus (P) focuses energy on strong root development và flowers, fruits & seeds, while also helping plants use other nutrients efficiently. A shortage of phosphorus leaves roots weak & flowers and fruit lacking.An increasing number of states & counties restrict the application of phosphorus lớn lawns due lớn the environmental concerns of phosphorus runoff into waterways. In these states or counties, homeowners can usually apply a lawn starter fertilizer that is high in phosphorus, such as UltraGreen Starter Fertilizer 22-23-4if a soil thử nghiệm indicates a nutrient deficiency. Kiểm tra with your local county extension agent on any nutrient application restrictions.

Potassium (K) enhances overall growth. It helps regulate root and top growth và keeps plants healthy and balanced. This affects all aspects of lawn và garden well-being, from cold và drought tolerance khổng lồ disease và pest resistance.


When lớn Use Different Ratios

Beautiful turf needs the vigorous growth and deep màu sắc plentiful nitrogen supplies, so lawn fertilizers have an N-P-K ratio with the first number much higher than the other two. Soil usually provides enough phosphorus & most of the potassium healthy grass needs, so the numbers for those nutrients are low.

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By understanding the basics behind fertilizer labels, you can choose the right products for your lawn và garden goals with"s portfolio of lawn and garden fertilizerscan help your lawn and garden reach its full potential for beauty và enjoyment.


1. Jolene Hansen, "How to lớn Identify and Correct Plant Nutrient Deficiencies," Earth Juice, May 2021