Over the past four years, the Finley Farmer Discussion Group’s irrigated and dryland canola results clearly show April sowing produces highest yields.
Last season dryland crops were sown dry from April 15 to 28 and emerged between May 7 to 15 with the best yields of 2tonne/ha to 2.6tonne/ha.
There were nine crops watered up or pre-watered in mid-April which emerged in late April/early May. These best yields were 2.5tonne/ha to 3.2tonne/ha.
Non-irrigated crops were sown dry between April 10 and 30 and the best yields were also 2.5tonne/ha to 3.2tonne/ha.
The current rainfall prediction is below average rain in the next few months.
For irrigators, management strategies include increasing water quantity to crops.
The group rule of thumb for watered-up canola on flood layouts is to have no rain predicted in the seven days after watering to reduce the risk of waterlogging.
Last year a few crops were watered-up in late April and suffered bad waterlogging damage from rain a few days after.
Spray irrigation farmers watered-up with 25-30mm so have less risk watering-up.
A Southern Growers canola variety sowing time project conducted by NSW DPI researcher Rowan Brill over the past three years has shown sowing time and variety are linked to high yields.
The trials were conducted using spray irrigation on Geoff McLeod’s Finley farm.
The highest yields of 3.5tonne/ha to 4tonne/ha from any variety were related to the start of flowering in early to mid-August with benefits of maximised biomass. This will still dodge heat stress.
The idea is to have flowering in the best three to four weeks environment.
Flowering too early in early to mid-July means less biomass and less yield potential.
In 2017 there was 25 per cent flowering in July which was too early and which is the tipping point for sclerotinia.
Farmers have already ordered their canola variety seed for this season.
To achieve the August flowering check, farmers watering-up in early to mid-April should consider sowing mid to longer season varieties such as 44Y88 CL, 45Y25RR and Hyola 577CL.
Farmers watering-up in mid to late-April should sow early to mid-season varieties such as Diamond, ATR Bonito TT, 44Y89CL and Hyola 575CL .
In last year’s group results, a 44Y24RR variety watered-up on April 17 started flowering on July 20 — a little early, but it yielded 3.3tonne/ha.
Two crops of Bonito TT sown on April 10 and 25, which emerged on April 17 and May 2 and were not irrigated, yielded 2.5tonne/ha and 3tonne/ha respectively, with flowering on July 25 and 28.
It is suggested dryland farmers dry sowing in early to mid-April sow mid to longer season varieties and early to mid-season varieties for mid to late-April sowing.