Contamination & Troubleshooting

Identify, prevent, and fix contamination. Visual guides for green mold, cobweb, bacterial infection, and common growing problems.

119 tips across 9 topics

Identifying Contamination

11 tips

  • What does green mold (Trichoderma) look like on mushroom substrate?
  • What does blue-green Penicillium mold look like on grain spawn?
  • What does cobweb mold look like on mushroom fruiting blocks?
  • +8 more...

Normal vs Contamination

10 tips

  • Are yellow droplets on mycelium contamination or normal?
  • Is fluffy aerial mycelium the same as cobweb mold?
  • Is blue bruising on mushroom mycelium actually mold?
  • +7 more...

Contamination by Timing

10 tips

  • What causes contamination that appears in the first 5 days?
  • What causes contamination that appears between days 7 and 14?
  • What causes contamination that appears after 14 or more days?
  • +7 more...

Contamination by Smell

10 tips

  • What does healthy mushroom mycelium smell like?
  • What does a sour or vinegar smell in mushroom jars indicate?
  • What does a sharp chemical smell indicate in mushroom growing?
  • +7 more...

Prevention & Sterile Technique

12 tips

  • Why does sterile technique matter so much in mushroom growing?
  • How do you use a still air box (SAB) properly for mushroom work?
  • How do you use a laminar flow hood properly for mushroom work?
  • +9 more...

Common Problems & Fixes

23 tips

  • Why do my mushrooms have fuzzy white growth at the base (fuzzy feet)?
  • Why are my mushroom pins aborting and turning brown?
  • Why won't my mushroom substrate pin after 3 or more weeks?
  • +20 more...

Rescue & Recovery Techniques

8 tips

  • Can You Save a Monotub with Early-Stage Trichoderma?
  • How Do You Rescue a Contaminated Agar Culture?
  • What Do You Do with Spent or Contaminated Substrate?
  • +5 more...

Growing Environment & Hygiene

20 tips

  • How Do You Set Up a Clean Room for Mushroom Growing?
  • What Is the Best Flooring for a Mushroom Grow Room?
  • How Often Should You Clean Your Mushroom Growing Area?
  • +17 more...

Advanced Contamination Diagnosis

15 tips

  • What Does Healthy Mushroom Mycelium Look Like at Each Stage?
  • Why Is My Mushroom Substrate Turning Yellow?
  • Can You Eat Mushrooms That Grew Near Contamination?
  • +12 more...