growth potential

I use the turfgrass growth potential (GP) all the time. I make use of the GP for all kinds of things, like predicting sand topdressing amounts, comparing locations, predicting nutrient use, checking overseeding dates, estimating mowing requirements, and many more.

I’ve been asked about the variance in PACE Turf’s growth potential (GP) equation. The variance adjusts the shape of the curve, as the chart above shows. With a lower variance, the GP drops quickly as t moves away from to.

I often express the temperature-based growth potential (GP) as a number between 0 and 1. That is, I don’t multiply GP by 100 to express it as a percentage. One advantage of keeping the GP on the scale of 0 to 1 is easy multiplication.

This can seem a bit abstract, the whole growth ratio thing. In this post, I go step-by-step through the reasoning behind this, and explain exactly which problem this solves. There’s a common question that people have when they start measuring the exact amount of clipping volume.

A question came up about optimum clipping volume and whether that quantity of clippings changes by season. That amount must change for any location at which there are seasonal changes in the weather.

Bentgrass grows more—or at least it produces more clippings for a while—when temperatures are higher than optimum for net photosynthesis. This means that you’ll typically see more clippings when the temperature is above the optimum for cool-season grass, even though the growth potential (GP) goes down at those high temperatures.

The PACE Turf topdressing rate spreadsheets have been updated with a new default starting value for monthly maximum topdressing sand. US units spreadsheet Metric units spreadsheet You can use the spreadsheets to input the monthly average air temperatures at your location.

I watched the Greenkeeper App meeting about organic matter, and I recommend you do too. The video has Doug Soldat, Bill Kreuser, and Roch Gaussoin talking about soil organic matter, rootzones, sand topdressing, and turf performance.

Does this sound about right? Matching sand topdressing to the growth of the grass works out pretty good when applying 1 cm3 of sand for every 1 cm3 of clipping volume.

I’ve sometimes explained the temperature-based turfgrass growth potential (GP) of PACE Turf in relation to the grass conditions at the Masters Tournament. The playing conditions at the Masters are superb, and the cool-season grass in that season is growing at near optimum temperatures.