From Granular to Liquid

Scheduling nitrogen

When fertilising our greens, we primarily rely on nitrogen to sustain turf health and stimulate growth.

We understand the need to underpin our maintenance programmes with sufficient levels of growth.

We also know to be “optimal” with our nitrogen because insufficient or excessive levels of growth might result in poor surface performance. The scheduling of our nitrogen inputs is of fundamental importance.

Granulars and liquids

The level of nitrogen input will vary throughout the year depending on conditions and the level of growth needed.

Generally, we use granular fertiliser to supply higher levels of nitrogen in spring and autumn when we are carrying out renovations.

Towards the main playing season, we switch to liquid fertilisers for less disruption, to achieve more consistent and measured growth responses, and compatibility with other important technologies like Primo Maxx II. Throughout the spring, we need to navigate variable growing conditions by applying appropriate fertilisers when growing conditions are suitable.

Granular to start

Early spring granular fertilisers (March-April) fall into two categories, either “high nitrogen” or “turf hardeners”.

High nitrogen formulations like Greenmaster Pro-Lite “Cold Start” 11-5-5 +8Fe or “Turf Tonic” 8-0-0 provide a strong growth boost for turf repair and recovery though top dressing (conditions permitting).

Greenmaster Pro-Lite

Turf Hardeners like the Greenmaster Pro-Lite “Invigorator” 4-0-8 + 4fe supply lower levels of nitrogen for steadier growth. We might use either or both types of these granulars depending on the situation and how the spring is playing out.

The move to liquids

We transition to our liquid nutrition programme when the course is dry enough for regular spraying and the surfaces are starting to take shape. This is generally when the greens are coming to the end of their renovation recovery and we need to finalise their refinement.

The aim of the liquid nutrition programme during this period is to support the refinement process without the surfaces “stalling” due to insufficient levels of growth. The transition from granulars to liquid is all about using the early liquids to keep up the momentum with the spring preparations.

Managing the transition

We begin our liquid applications to cover the tail of the earlier granular and create a seamless transition.

During this initial overlap between our granular and liquid applications, we need to be clear what level of nitrogen is required to support the surface preparations. The nitrogen requirement largely depends on the level of recovery needed and the amount of top dressing being applied.

We might apply 1-2 kg/ha of N weekly under minimal top dressing, 3-4 kg/ha for moderate dressing and recovery, and 5-6 kg/ha for heavy dressings and strong growth. We need to cater for our own situation.

For example

If we need to get through a moderate level of top dressing to help finalise our preparations then we might be aiming to supply 4 kg/ha of N per week for a couple of weeks before tapering down towards our summer levels (maybe around 2.5-3 kg/ha of N per week).

So, we would need to estimate the nitrogen release at the tail end of our granular application and calculate what additional nutrient is needed from our initial liquid.

For instance, towards the tail end of a Greenmaster Pro-Lite “Invigorator” release we might estimate a remaining contribution of 2 kg/ha per week for a couple of weeks.

Knowing this, we would apply Greenmaster Liquid “High N” (33-0-0) at 15 L/ha to add 2-2.5 kg/ha per week for the next couple of weeks to hit our target. We would then review the situation to decide what level of input is required for the next application (but this time without any major overlap to consider).

Initiating PGRs

A key technology that we will also be wanting to introduce during this time is the plant growth regulator Primo Maxx II, which forms a vital part of our surface refinement programme.

We commence Primo Maxx II applications when soil temperatures consistently reach 8-10°C or when growth potential gets to 40% (available on Syngenta Turf Advisor app).

Initially we would start with a Primo rate of 0.2 L/ha applied every 3-4 weeks and then shorten the frequency to every 2 weeks as conditions improve. Primo requires nutritional support (2.5-3 kg N/ha per week) and so slots in nicely at this time.

We then monitor turf responses (or use GDD) to refine application rates or intervals to achieve consistent regulation.

Surface perfection

Transitioning from granular to liquid nutrition in spring requires planning and flexibility.

We need to supply sufficient nitrogen for early-season recovery and surface refinement, tailoring our inputs to conditions. A combined granular and liquid approach, carefully managed, can support a seamless transition from renovations to surface perfection.

Thoughtful scheduling and using the right technologies are key to success.

For further advice on liquid nutrition programmes or product recommendations, contact the ICL Turf and Landscape team.