However, analysts visiting Geest's new dedicated salads facility for M&S said the outlook remained bright, with new business likely to come from moves by Tesco and the Co-operative Group in the c-store sector, and strong growth in most of Geest's key markets.
Geest said full-year operating profit would be no less than last year's. Group sales for the 10 months to October were up 16%.
While sales growth in prepared salads improved from the 6% in the first half to over 10% in July-October, it is still some way behind the 18% growth the company was enjoying in the spring.
West LB Panmure analyst Charles Hall said: "The market took fright at the statement, but most of us didn't have to change our numbers."