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Understanding How Slow Release Nitrogen Fertilizer Works

An important trend in professional landscaping is utilizing slow release fertilizer instead of quick release fertilizer.

In this FAQ, Christina Burton, Maintenance Channel Manager for Horizon, explains what slow release fertilizer is and why it can contribute to a more efficient, cost-effective fertilizer program.

Highlighting How Slow Release Fertilizer Works - Video Transcript

So what does it mean for a fertilizer to be called slow release? It’s a common term these days. Used in a lot of different fertilizers.

What we’re really talking about is the Nitrogen content. Being able to release Nitrogen specifically over time to plants so that there’s less flush growth and more extended growth. So you end up with better plant health, but also it’s more efficient and more cost-effective.  

So you might see on a bag, for example, of say a 24-3-12. So of those 24 units of Nitrogen, 12 of them are still immediately available.

So there is a misconception that slow release means you’re gonna have to wait a long time to see a result. And that’s certainly not true. Particularly if it’s only a percentage that is slow.

So half of that is still going to be available right away. You’ll still see immediate greening. Whereas the other half is being released over time. So extending the amount of time before you have to come back again and fertilize.

So to show what this looks like and where you can really see both the benefits in turf health and in cost-effectiveness.

Kinda the old way with quick release only, would be fertilizing here in Week 1. You get a huge shoot in growth. Mowing like crazy. And it comes down pretty quickly. You’ve got these peaks and valleys of how the turf looks. And you gotta come back and fertilize again about six weeks later. 

Whereas the slow release, and again it varies the time whether we’re talking 10 weeks, 12 weeks, 16 weeks. But again, generally speaking, you can count on at least twice the time of a quick release.

Fertilize in Week 1. A much less steep curve of spike. It’s growing consistently, but not to where you’re mowing a bunch and then it tapers off. And you’re not having to fertilize until about 12 weeks later.