Dear Grower,

The start of February sees the Balonne in a position for good yields, as the flowering period draws to a close with great boll numbers and low insect pressure throughout the season, despite the fact that rainfall was quite sparce.

Water budgets have been depleted, and many growers are looking to finish off crops early, with many likely to be at least one water short. 

Still, what is there in fruit load is looking promising and if we have had to suffer a dry summer, there are hopes the region can experience a dry pick and finally get the quality to match the yield after the last two seasons wet finishes.   

Approaching cut-out

For many in the region, the flowering period is almost over as the crop approaches cut out. Cut out is a natural physiological stage in cotton plant development when the crop ceases to produce new fruiting sites (squares). This occurs when the demand for carbohydrates by developing bolls exceeds the supply produced by the leaves. An approximation of cut out timing is when a crop reaches an average of 4 nodes above white flower (NAWF). At this point, the crop has attained approximately 95% of its harvestable yield. 

For some the crop will reach this point naturally and for others they will bring it forward using mepiquat chloride. Some considerations for managing cut out are: 

• Maintaining fibre quality through timely harvest (The timing of cut out directly influences when the crop matures, later cut out, later maturity). 

• Ensuring effective defoliation practices to reduce trash 

• Avoiding excessive immature bolls that may increase nep 

• Is water running short? Should we pull the crop up to preserve what is there. See below.  

Running short of water at the end of the season

Water stress significantly impacts cotton growth, development, and yield, with effects varying depending on the timing, severity, and duration of the stress. Peak flowering to late flowering represents the highest risk period for yield loss. 

As mentioned previously, a management strategy for being short an irrigation or two at the end of the season is to cut the crop out and preserve fruit that is already on the plant, ensuring bolls present are not stressed at the cost of higher boll numbers. Alongside yield, quality can also be affected, particularly micronaire.  

Season so far  

The season so far has been a hot and dry one - the hottest season in the past 10 years, with an average temperature of 27.7^oC (Oct 1 – 26 Jan). 

A deeper look into the weather this season shows though while it might outdo the 2019/20 season in terms of average temperature and overall day degrees accumulation, it hasn’t experienced as many days over 40^oC (2016/17 also has more). However, at the time of writing this also looks likely to be broken, as the region experiences a prolonged heat wave predicted to last into early February. Total rainfall is down, with just under 100mm recorded at the St George airport as of 27 January. 

Many fields are likely to run short at least one water from the combination of low rainfall to refill the dam and heat throughout the season.  

In terms of how the crops are looking, CottonTracka has been helping with snapshots out in the field.  

Here is an example of a field with CSX 1257B3XF at St George. Initially slow to fruit up, it did accumulate bolls during peak flowering. The rapid decline in flowering and boll numbers tapering off is likely linked to the decision to apply cut-out rates of mepiquat chloride earlier than desired. Water was running low in this field and it will likely be short a water. The decision was made to cut it out early and preserve what fruit it already had.  

Coming up

Field walks

To showcase the new XtendFlex^®  varieties, CSD intend to conduct field walks in the region this month with one planned for the 18th February at Harlequin, near St George. CSX 1320B3XF will take centre stage, as it gears up for commercialisation. There will be another field walk in the region in March, closer to picking, for another look at CSD’s varieties.

Cotton course

If you feel like either you or your staff would benefit from a little bit of extra cotton knowledge in 2026, then it is worth remembering that the new CRDC Cotton Course will be run by the University of Sydney 10-12th March this year. Currently there is a discount available and there are still places.

- Larissa

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