It is important to start clean! A thorough cleaning of bulb handling, planting and cooling facilities will help to avoid problems in forcing, especially with diseases such as Trichoderma. See our fact sheet on Trichoderma. This disease is promoted by very heavily rooted plants. When tulips are massively rooted in pots, the lack of soil among the roots makes the roots more susceptible to drying out, salt accumulation or any number of other stresses, and weakened roots are thought to be more susceptible to the pathogen.
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