Cotton planting considerations - part two

28 September, 2017

Early_plants
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In the second instalment of this two-part series, CSD’s Extension & Development Agronomist for Central NSW, Bob Ford investigates the impact of temperature and planting date on germination.

Planting – “do it once, do it right"

Without a uniform plant stand, the season can be over before it begins – but how do we achieve a good plant stand?

1. Preparation – complete ground preparation early and ensure the planter is ready to go when required. Well maintained machinery will enable a smooth transition into the planting operation.
2. Create a firm, consolidated seed bed to facilitate uniformity across every plant row, in terms of seed placement and depth. Check the most appropriate plant population for your scenario.
3. Check your planter depth and speed – around 8-9 km/hour is recommended for planting, and seeds should be planted no deeper than 5cm, regardless of moisture conditions/irrigation plans.
4. Manage issues such as cloddy soils, crusting, trash content, bed slump and slot compaction.

Temperature – do we understand it at planting time?

Planting date and temperature play a vital role in the success of failure of seed germination and establishment. Research by CSD’s Quality Assurance team has shown that planting into cool soils will prolong seed establishment. In soil temperatures under 12°C seeds can take 110 hours to put out a 2mm radicle (90% germination), but when soil temperatures are at 14°C seeds take 96 hours, and at 16°C it will take 72 hours. Furthermore, the longer the seed takes to establish the more susceptible it is to soil insects and seedling disease.

The impact of temperature on germination

CSD has a number of weather stations with soil temperature sensors placed across many regions of the cotton industry, which form the FastStart™ Soil Temperature Network. These sensors are a real time measure of the soil temperature at 10cm and can be used as a guide to whether conditions are suitable for planting cotton in the areas where they are situated. Ensuring that soil temperature is above 14°C at 8am (AEST), as well as checking that the forecast temperatures for the week following planting are on a rising plane, will give the ‘green light’ for planting.