Author: David McRae – IPF Technical Agronomist – IPF Technical Agronomist, Broadacre & Pasture, Agronomy and Ideation

Establishing strong, uniform summer crops starts with getting early-season nutrition right. For cotton, maize and sorghum, phosphorus (P) and zinc (Zn) are critical for seedling vigour, root development, and early stress tolerance – all factors that drive crop potential from the start. Ensuring seedlings have immediate access to these immobile nutrients is more important than ever – especially if using the newer smaller-seeded cotton varieties or if establishing sorghum in cooler soils.

Why they matter early

P and Zn deficiencies during establishment can significantly restrict growth, leading to stunted, pale seedlings with underdeveloped root systems. These plants are less resilient to insect pressure, disease, and weather variability – all common risks early in the season.

Starter applications of P (2-4kg/ha) and Zn at planting can offset this risk. For maximum impact, these nutrients must be placed where emerging roots can access them, especially in cooler soils where root activity and nutrient mobility are limited.

Depth and distribution

In systems relying on stored subsoil moisture, deep banding P and Zn (20-40cm) every 5-7 years, combined with lower starter rates at planting, ensures nutrients are available throughout the season, even in dry surface soils where shallow bands may be inaccessible.

Soil testing is key. Sampling both the 0-10cm and 10-30cm layers allows you to understand nutrient availability and guide long-term replacement strategies.

Why Flowphos?

EASY Liquids’ Flowphos delivers P and Zn directly into the seed furrow in a uniform, low-rate liquid stream, ensuring each seedling has access to vital nutrients. Unlike granular fertilisers which can be patchy at low rates, Flowphos evenly coats the root zone, enhancing early uptake.

Flowphos can be tank-mixed with compatible insecticides or fungicides to protect seedlings from early pest and disease threats. However, always consult your EASY Liquids sales agronomist for compatibility.

Application system tips

Accurate liquid fertiliser delivery depends on proper system setup and maintenance. Hard water containing high levels of calcium, magnesium, or carbonates – or with high electrical conductivity (EC) – may cause compatibility or mixing issues.

It is recommended that system cleanliness and water quality is checked before preparing in-furrow mixes. Residual material left unflushed can react with the next application, forming precipitates or crystals that cause blockages and affect flow rates. Cleaning between applications helps avoid compounding problems.

Most systems use orifice plates to meter flow, but these can easily block at low starter rates due to their small openings. Switching to friction tubing or line meters and maintaining consistent pressure (1-2.5 bar), helps ensure steady flow and reduce downtime. Friction tubing is preferred for low-volume starter applications, while line meters suit higher-volume systems. For growers looking to update their system, visit Liquid Systems for more information.

Takeaways for planting success

  • Cooler planting conditions reduce both nutrient uptake and root growth – early P and Zn are essential.
  • Flowphos ensures uniform nutrient placement at low rates for stronger crop establishment.
  • Review and update your liquid application system to support precise in-furrow delivery.

Further information

For further information, or if you’d like to talk through your program or setup, please feel free to contact David McRae, IPF Technical Agronomist, Broadacre & Pasture at: david.mcrae@incitecpivot.com.au or 0477 987 321.

For Flowphos application rates or compatibility advice, speak with your local EASY Liquids Sales Agronomist:

  • Bob Moorfield – 0488 067 736 (EASY Liquids Whitton)
  • Matt Urquhart – 0429 789 298 (EASY Liquids Moree)

For pricing and availability, contact your local reseller.