Sowing earlier with slower maturing varieties increases the length of the sowing window, therefore increasing the probability of sowing timely.
If only depending on later sowing with quicker maturing varieties one is more vulnerable to sowing time being too dry or too wet, therefore pushing sowing into the “too late” and potentially very low yielding option. Early sowing with slower maturing varieties means they can head about the same time as later sown quicker ones.
It also allows crops to root deeper, often increasing their access to more sub soil moisture and nutrients. It is common, but not always the case, for earlier sown crops on good sub soil moisture to yield more than later sown crop with quicker maturing varieties.
The following, roughly in order of sowing time, are some of the main wheat varieties for early sowing. Varieties with winter habit are suited to early sowing except in warmer north-west NSW areas.
Varieties like Kittyhawk and ‘Longsword’ combine improved disease resistance with high yield potential and for many areas have a sowing window from mid-March to mid-May.
Sunmax (APH quality) is slightly earlier maturing than Sunbrook and the next slowest of the spring varieties. Its main sowing window is second week of April to early May.
Suntime (2015), also a APH variety has yielded high and suits sowing around from around third week of April. Suntime has good stem and stripe rust resistance and good tolerance to nematodes (P thornei).
Lancer, while a 2013 release, fits the high yielding category and suits sowing around the third week of April to mid-May. APH quality, excellent resistance against the three rusts are among its features.
Coolah (2016) is high yielding, APH quality, has excellent resistance to the three rusts and useful tolerance to nematodes (P. thornei).
DS Darwin (2015), Beckom (2015) and Mitch (2014) are other relatively new releases that fit into the higher yielding category for early May onwards sowing.
This list is not comprehensive for earlier sowing varieties. It is important to assess varieties for all their agronomic, quality, and disease resistance characteristics. Some varieties may have low rankings for one or more of the rust diseases and will require planned strategies to reduce risk.
In some situations, best tolerance to nematodes or diseases like yellow leaf spot or crown rot need to be considered. Acid soil tolerance is an advantage in some soils. Some new varieties have Clearfield herbicide tolerance and a few have pre-harvest sprouting tolerance.