"There have been one or two times last year when, for a variety of reasons, she wasn't able to completely articulate exactly what we were doing in a coherent way, and that caused some problems. I think she would accept that. But I think she's hugely talented and has learnt from those experiences."
He said Ms Parata was not solely to blame for the blunders of the year. Education was a tough portfolio for anyone in a National Government and it was no surprise teacher unions were calling for her sacking.
"I can't name a minister of education in National that the unions haven't wanted to see sacked."
Green Party education spokeswoman Catherine Delahunty said Mr Key's intention to keep Ms Parata in the role "adds insult to injury for students, teachers and parents".
"Hekia Parata has time and time again frustrated the education sector, students and families with her damaging plans for education and her poor communication of those plans."
After hearing Mr Key's comments about Ms Parata, Labour's deputy leader Grant Robertson tweeted that he would hate to see Mr Key's definition of a poor communicator.
Ms Parata refused to front on the resignation of Ms Longstone just before Christmas and went on holiday.
Yesterday, the minister sent out a press release but her office said she was still unavailable for other comment until next week.
Mr Key said the reshuffle would not be major. It was necessary because of the departure of Dr Smith, who will leave next month to become the High Commissioner in London.
He is expected to be replaced by either David Carter or Maurice Williamson - and Nick Smith could be returned to the ministerial benches to take the appointee's place.