As growers prepare to make planting decisions for the 2026/27 season, Cotton Seed Distributors (CSD) has refined its soil temperature guidance to help identify when conditions are right to plant. 

 CSD Technical Agronomy Lead, Dr Michael Bange, said the updated advice would help growers make more informed planting decisions, particularly when conditions are marginal. 

 “Planting is one of the most important decisions growers make each season and getting the crop off to a strong start can have a significant impact on its performance,” Dr Bange said. 

“We know growers are making these decisions based on a range of factors, and soil temperature is an significant, if not the most important part of that picture. 

“The adjusted advice gives growers a clearer understanding of how soil temperature and seed energy can influence establishment, particularly when conditions are marginal. We wanted to ensure that the recommendations and tools gave the lower density seed types every chance to succeed.” 

The updated recommendations recognise differences in the establishment performance of normal and low density seed types, providing growers with clearer guidance when assessing planting conditions. 

Under the updated advice: 

• Soil temperatures below 16°C are classified as ‘unsuitable for cotton planting’ 

• Temperatures in the range 18-20°C previously characterised as ‘good’ for all seed types, are now considered ‘marginal’ for low density seed types. 

Soil temperature plays a critical role in cotton germination, emergence and early seedling development.  

CSD research along with knowledge from cotton literature has continued to demonstrate that average soil temperatures below 16°C can limit germination and considerable restrict emergence and establishment while warmer conditions provide a more favourable environment for strong emergence and early growth. 

The updated advice is designed to complement the FastStart™ Field Forecast tool, which uses real-time soil temperature observations and weather forecasts to provide a site-specific seven-day outlook for soil temperatures. 

Along with the weather station providing the  the 8am soil temperature on a given day the  average daily forecasted soil temperatures, is there to assess whether conditions are suitable for planting and how those conditions are expected to develop after planting. 

Dr Bange said importantly, this isn’t about making the planting decision based on one number alone.

“Growers should look at what the soil temperature is doing now, what is forecast to happen over the following week and the type of seed being planted, while also considering their conditions in the field itself; noting that there can be differences between the field and the FastStart weather station where the soil temperature sensor is located.” 

“The aim is to help growers put seed into conditions where it has the best opportunity to establish successfully and get the crop off to a good start.” 

Further information on optimum soil temperatures for planting can be found at csd.net.au.  

Access to the FastStart™ Field Forecast tool is available via the CSD website, with an active CSD Membership.