(Adds details on capital raising, context, executive quote)
Aug 1 (Reuters) - Australian crop protection company Nufarm Ltd NUF.AX on Thursday cut its fiscal 2019 earnings guidance and said it would raise about A$97.5 million ($66.8 million) through a share placement with Japan's Sumitomo Chemical Co Ltd 4005.T .
The company expects underlying core earnings for the year to July 31, 2019 of about A$420 million ($288 million), compared with its previous guidance of A$440 to A$470 million, Nufarm said in a statement.
The pesticides and crop seeds producer said the cut was due to flooding in parts of the United States and drought in Australia, along with supply constraints on products sourced from China that had led to higher costs.
"It's been a difficult year, with external headwinds impacting performance in three of our four major markets," Nufarm chief executive Greg Hunt said.
The company said it also expected to report about A$50 million of significant items, which will be excluded from its 2019 core earnings.
Canada's Nutrien NTR.TO , the world's largest fertilizer maker, recently missed expectations with its quarterly earnings due to floods in the U.S. midwest. = 1.4603 Australian dollars)