Fertilizer

Minimum levels for sustainable nutrition—MLSN—is a modern method for interpreting soil tests for turfgrass.

This is how I think everyone should do it. Make nutrient applications that have a site-specific ratio of nitrogen (N), phosphorus (P), and potassium (K). I write this because I’ve had some questions about ratios and about fertilizer nutrient analysis, and I want to explain this in a general way.

Doug Soldat joined me for an ATC Office Hours discussion about leaf nutrient analyses (tissue testing) for turfgrass. I’ve embedded the video at the end of this post, link to it here, or listen to the podcast version here.

One of my favorite publications is the The Greenkeeper annual yearbook by Ikki Publishing Company. This yearbook includes annual maintenance summaries for golf courses in Japan. This is a type of practical information that I find really useful.

Joe Hollier wrote to me a few weeks ago asking if I could write something about MLSN for the STANZ newsletter. I sent this quick reply: Gosh, this is the kind of thing I should say no to because I’m quite busy and don’t want to add more things to do to my list.

You’ve probably listened to one of my seminars in which I explained why conventional nutrient guidelines for turfgrass are broken. Jackie Guevara’s thesis on “Effects of Different Soil Testing Philosophies on Creeping Bentgrass and Annual Bluegrass Putting Greens” is an excellent demonstration of this.

When Bernd Leinauer introduced me prior to this talk, he mentioned that I’m one of the most controversial turfgrass scientists today. And the reason for being controversial happens to be the very topic of this presentation1 that I’ve uploaded today to my YouTube channel.

GCM Magazine has another article about the SLAN and MLSN methods for soil test interpretation. The article summarizes Jackie Guevara’s research (with Kevin Frank at Michigan State University) into turfgrass response when P and K applications are made based on MLSN.

These pots of variegated tropical carpetgrass (Axonopus compressus) received an application of granular 16-16-16 fertilizer twelve days before this photo was taken. The grass on the right responded with a lot more growth than did the grass at left.

I’ve explained how MLSN works by telling a story about beer. Specifically, about a natural and logical method to figure out how many beers to buy at the store prior to an upcoming party.