The Q&A Archives: Improved Soil for Seed Starting

Question: What temperature do you need to heat soil to sterilize it? I seem to have been invaded by a fungus that's killed off nearly everything I had started indoors. The seedlings are shriveling, with the narrowing in the stem that looks like damping off fungus.

Answer: To pasteurize soil, it will take 30 minutes at 180 degrees F. The advantage of pasteurization can be lost if faulty sanitation allows the reintroduction of disease organisms. The following suggestions will help maintain soils in a disease-free condition: 1) sterilize all seedling soils at the same time. 2) disinfect benches, tables, pots, trays, etc., before dumping or using clean soil. Disinfect all tools that come into contact with clean soils. 3) do not transplant infected seedlings or plants from out-of-doors or from diseased trays into clean soil. 4) do not handle clean soil with dirty hands or tools. 5) keep the nozzle of watering hoses or cans off the soil at all times. You did not say whether the soil you used was actual garden soil or a sterile soil-less seedling mix.

« Click to go to the homepage

» Ask a question of your own

Q&A Library Searching Tips

  • When singular and plural spellings differ, as in peony and peonies, try both.
  • Search terms are not case sensitive.

Today's site banner is by cocoajuno and is called "Here's looking at you."