Depending on planting date, the maximum and minimum soil
temperature at planting depth was 1–2 ◦C higher under the film
compared with the control temperature, but was not as high as
the previous season due to this being an earlier planting (Table 2).
The one exception was the minimum soil temperature from the
first planting, which was 0.2 ◦C cooler beneath the film compared
with the control. Soil water was monitored using GBLite gypsum
blocks since the water probe (used in 2009) required drilling holes
in the film to insert the sensor compromising the integrity of the
film and the measurement of soil water. The soil was consistently
wetter under the film (lower soil water potential) compared to the
control (Table 2). Cotton emerged 3–4 days earlier under the film
compared with the control plots (data not shown) and the number
of emerged plants (plants/m) declined with the later planting dates
as the seedlings were unable to penetrate the film and died compared with the control (Table 3). There was no statistical significant
difference in lint yield or fibre length between treatments: fewer
plants were larger under the film and maintained yield. However,
fibre strength and micronaire was statistically significantly different between the film and control, as well as micronaire between
planting dates (Table 3).