Tim de Kok, head grower of the Madison, Maine-based greenhouse tomato company Backyard Farms, has resigned.

Backyard Farms’ head grower leavesThe company pulled 420,000 tomato plants in July because of a a whitefly infestation, and then destroyed the replacement plants because they were deemed inferior.

The company, however, reported de Kok’s departure was planned, and not related to the problems which is expected to halt shipping until January.

De Kok was also Backyard Farm’s general manager, He had worked in U.S. and overseas greenhouses, and he left the company on Aug. 19, according to the Portland Maine-based Press Herald newspaper.

Backyard Farms is searching for a successor, according to the Press Herald.

The setbacks also caused Backyard Farms to lay off some workers; others will be furloughed, according to news reports.

Backyard Farms sells greenhouse tomatoes to a variety of retail chains throughout the Northeast.