Wet field conditions prevented many Prairie farmers from planting their crops this spring. (CBC)

Up to $450 million will be made available to help flooded-out Prairie farmers, the federal and provincial governments say.

Under a plan announced by agriculture ministers Thursday in Saskatoon, affected farmers in flood-ravaged areas in Alberta, Saskatchewan and Manitoba will receive about $30 per acre. The money is above what's available through crop insurance and other farm aid programs.

The deal comes following one of the wettest springs on record, leaving millions of acres of farmland unseeded.

"It's unprecedented in what I recall," federal Agriculture Minister Gerry Ritz said. "I've been around a farm all my life and I've seen wet, but never like this."

The majority of the money, about $360 million, will go to Saskatchewan, which has been hit by a series of flash floods and wet field conditions that have prevented farmers from planting their crops. Ottawa is paying 60 per cent of the tab and the province will pay 40 per cent.

Normally, about 32 million acres for crops like wheat and canola are seeded in Saskatchewan, but this year, about 12 million acres are either under water now or could not be seeded earlier in the season.

"It's not just a Saskatchewan problem," Saskatchewan Agriculture Minister Bob Bjornerud said. "Eighteen per cent of Canada's productive farmland on the cultivated side will not be producing this year. Here in Saskatchewan, we have just around the 46 per cent mark of all the cultivated land in the country, so you can see how dramatic this is to the whole country, not just Saskatchewan."

Agriculture ministers in Alberta and Manitoba say their farmers have been hurt by excessive moisture and flooding, too, and the money will help.

The announcement came the same day Prime Minister Stephen Harper was touring flooded areas around Yorkton, Sask., one of dozens of Saskatchewan communities that have been declared disaster areas after flash floods.

"Our farmers work hard through all conditions and circumstances to provide food for people across this country and around the world," Harper said in a news release. "Our government will help them recover from the exceptional circumstances caused by the rains and flooding."

Farmers will be able to pick up the application forms at their local crop insurance offices.