Ginseng continues to senesce in most gardens. Pest issues that develop on foliage at the stage will have no impact on root growth. However an application of a broad spectrum foliar fungicide at this stage can reduce inoculum for next season in gardens not harvested this year.
Root rot can continue to develop and spread after the tops senesce. Phytophthora can still become an issue if we receive substantial rainfall over the next few weeks. Ridomil is only registered for three applications per season, and those applications are usually completed earlier in the season. Aliette application will have no benefit once tops are mostly senesced, because it needs to be taken up into healthy leaf tissues in order to activate plant defences. As result, Maestro is the only registered Phytophthora product that can be applied if Phytophthora becomes an issue at this stage of the season. If Rhizoctonia is a concern, Allegro is the only product registered for Rhizoctonia suppression after the spring of the seedling year.