THE Victorian grain harvest has defied heat and rain to reach its half-way point.

Bulk handler GrainCorp said this week it had so far received 1.44 million tonnes of grain, with harvesting in the Mallee nearing completion and other areas slowing down.

Last week, extreme weather hampered the harvest, first with hot days followed by rain.

GrainCorp spokesman Angus Trigg said temperatures hit 48C at the company's grain storage at Ouyen last Thursday.

Several crop fires broke out in the southern Mallee and northern Wimmera the previous day as temperatures climbed to the high 30Cs.

Harvesting ground to a halt on Friday as rain hit most districts.

But Mr Trigg said the rain had no substantial impact on grain quality and yields.

Growers reported mixed results with their crops but overall were happy with yields, given the dry finish to the season.

Bernie Mulquiny, of Wooroonook, west of Charlton, said he had 120ha of scout wheat, which should yield more than four tonnes a hectare.

He said it was on box swamps near Wooroonook Lakes, which flooded at harvest time two years ago, and that some of the water lay 1.5m deep for a year.

He said he expected the wheat to make the Australian Premium White grade. During the floods Mr Mulquiny got topsoil, carbon and nutrients from other farms.

His neighbour, John Brennan, had a patch on swamp ground flooded in 2010 which the harvester yield monitor recorded at 6.5 tonnes a hectare.

Further west, most of the wheat delivered to GrainCorp's storage at Beulah made the APW or Hard 2 grades. Grower Brad Moore said the district had only about 100-125mm of growing season rainfall.

"We were hoping our wheat would make the APW grade," he said.

"Some went ASW but most was APW. We were more surprised with the yields. Wheat crops varied between 1.5 tonnes/ha to four tonnes/ha."

Crops at Sheep Hills, south of Warracknabeal, also yielded well. Grower John Goodwin harvested four tonnes/ha barley crops making malting grade.

He said yields were better than other crops on land near Jeparit.