How to deal with soil-borne diseases in pots?

Remove and replace potting mix each season or solarise it — place moist soil in a black polythene bag in full sun for 4–6 weeks. Add Trichoderma viride or Pseudomonas fluorescens powder to the new mix. Ensure pots have adequate drainage holes. Soil-borne Fusarium and Pythium build up rapidly in reused mix under India's warm temperatures.