Will trench celery stand any frost, first time of growing only grown self-blanching before.
It was always said that trench celery tasted better after a touch of frost. Last year we grew trench celery quite successfully, and it lasted well into the cold weather. (This year we lost all our seedlings :( but that's another story)
Ours was good until Christmas, but by the end of January it was looking pretty sad, and we junked the last few plants. I'm not sure whether they succumbed to frost damage or heart rot. Next year we're going to dress them regularly with calcium nitrate, which is supposed to prevent heart rot.