Effect of soil amendments and fertiliser types on turfgrass visual quality, growth rate, playing quality and thatch characteristics on a low-fertility, USGA-spec. creeping bentgrass putting green, phase II


One-year extension of a project started in 2016 to evaluate Melspring/Olmix’ sand/soil improvers Stor-it and Matrix, both containing natural zeolite and Matrix also containing seaweed.  The amendments were mixed at 10% (v/v) ratio into the top 5 cm on a USGA-spec. green with an initial organic matter content of 0.8% (Sphagnum peat) before sowing creeping bentgrass on 9 June 2016. Stor-it and Matrix increased the pH and cation exchange capacity of the substrate and accelerated bentgrass establishment significantly compared with the unamended control. The fastest grow-in was achieved with Matrix,  which, unlike Stor-it, contained 1.1% N and increased the water-holding capacity of the upper rootzone.

After grow-in was completed, Stor-it and Matrix continued to be added in the monthly topdress. Plots were split into four subplots with Melspring’s organomineral fertiliser Marathon or the readily available liquid mineral fertiliser Wallco (control, 2-wk interval, but same total N rate) under two irrigation regimes. During this period, both Stor-it and Matrix resulted in firmer greens, while overall turf quality was improved by Matrix, but reduced by Stor-it, compared with the unamended control.  Matrix also incurred two disadvantages: reduced root depth and more microdochium patch. The effects of Marathon vs. Wallco fertiliser were mostly insignificant except that Marathon gave lower N concentration in turfgrass clippings in both 2016 and 2017, suggesting that this fertiliser needed more time to trigger a microflora conductive to mineralisation.

In phase II of  the project, starting 1 May 2018,  the protocol was modified to optimise use of Stor-it, Matrix and Marathon under Nordic climate conditions. Marathon TCR (Turf Core Renovator) was introduced as an alternative to topdressing with Matrix during the first part of the season (until 1 Aug.), after which Stor-it was used in all treatments to lower the soil water content and enhance rooting before winter. Furthermore, application of Marathon was discontinued in mid-September, one month before Wallco, to avoid microdochium patch in late autumn and winter. These changes clearly improved the performance of the Melspring/Olmix products in 2018.  In particular, the combination of  Marathon and Marathon TCR improved turfgrass recovery after a tough winter and alleviated the potentially negative effect of autumn-applied Stor-it on turfgrass quality in spring.

Trygve S. Aamlid

Trygve S. Aamlid, The Norwegian Institute of Bioeconomy Research (NIBIO), Dep. Urban Greening and Environmental Engineering, Turfgrass Research Group, Landvik, Reddalsveien 215, 4886 Grimstad, Norway. Phone: +47 90528378. E-mail: trygve.aamlid@nibio.no

Category: Water, nutrients, construction
Status: Ongoing
Project period: 2016-2018

Fundings (kSEK)

                                        2017    2018     Total
STERF                                    0           0            0
Other sources                     370          21        391
Total                                  370          21        391

Project objectives

  • To study the effect of Melspring’s soil amendments Matrix and Stor-it and Marathon fertiliser on turfgrass quality, growth rate, playing quality and organic matter accumulation over a longer period than was possible during phase I of this project.
  • To specifically study the effect of Marathon TCR and a revised application scheme for Matrix and Stor-it adapted to Nordic climate conditions.