Fertilizer by the Numbers
When you buy fertilizer, do you know exactly what you’re buying without having to ask someone or pick the container up and read through all that print? If not, there are two great ways of determining it. One way is already there for you, in the form of those three numbers that always appear. They tell you everything you need to know at a glance.
Trouble is, many people, even though they may know what the numbers stand for, aren’t sure exactly what the product will do, and ultimately seek out the advice of an employee or begin reading the often-heavy bag. Here’s how to decipher the numbers, know what they mean, and a very easy way of remembering what they do.
The three numbers indicate, in order, the relative amount by weight, of nitrogen, phosphorus, and potassium in the container, and they’re abbreviated N, P, and K respectively. But what if you’re not sure whether you want nitrogen, phosphorus, potassium, or all three? All you have to do is remember three words: green, flowers, hardy. Say it over a few times, and you’ll remember it. Green, flowers, hardy – green, flowers, hardy. Not out loud, though, or someone might look at you a little strange. That’s what those numbers are telling you. And they’re always in that order, on every container of fertilizer, from every manufacturer. Now here’s precisely what nitrogen, phosphorus, and potassium will accomplish.
Nitrogen (N) promotes leafy, green growth that leads to a healthy lawn, beautiful shade tree, or a thick, lush hedge. If you want a quick green-up for your lawn, think back to green, flowers, hardy. Green comes first. So you want a fertilizer with a higher first number, such as 28-4-8. This type of fertilizer will do the trick, since it contains 28% nitrogen.
Phosphorus, the second ingredient (P), stimulates root growth and promotes flowering and fruiting. This is what you’ll need when planting a new tree, or helping your annuals and perennials put on a great color show. By now you’ve probably remembered the three words, so go with the second one here. For brilliant flowering, look for a product with a high second number, such as 4-12-0.
The last number is potassium – or potash (K). It contributes to cold hardiness, heat tolerance, and disease resistance. In other words, overall hardiness of the plant. Many people apply this in the fall to help plants survive the long winter. Green, flowers, hardy again. If hardiness is what you’re seeking for your lawn or plants – you guessed it. A higher last number, such as 8-4-14.
General, all-purpose fertilizers have three equal or nearly equal numbers on their containers.
At this point, you may have noticed that these numbers don’t add up to 100%. So what’s the rest of the stuff in the container? It’s a carrier designed to distribute the fertilizer more evenly around your yard and garden.
No matter which type or brand of fertilizer you’re applying, always follow the directions. Set your spreader accordingly. Too much can do more harm than too little. Avoid using a hand-held or broadcast spreader on a windy day, since it can scatter the fertilizer into unwanted areas. Make sure your spreader is in good condition, so it doesn’t accidentally over-apply anywhere. And move the spreader off the lawn to fill it.
So now you have it – fertilizer by the numbers. Next time you visit your local garden center, remember those three words, and you’ll know exactly what you’re looking for with just a quick glance.
