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Stem Rot

Stem rot in cannabis plants is a serious condition typically caused by fungal pathogens, which can lead to significant damage or loss of the plant if not addressed promptly.

Causes

1. Fungal Infections: The most common fungi responsible for stem rot include Botrytis cinerea (gray mold), Sclerotinia sclerotiorum (white mold), and Pythium species.
2. Poor Growing Conditions: High humidity and poor air circulation can create favorable conditions for fungal growth.

Symptoms

1. Discoloration: Dark or brown spots on the stem near the grow medium (sponge), which may eventually turn black.
2. Softening and Wilting: The affected part of the stem becomes soft, and the plant may wilt.
3. Mold Growth: Visible mold growth on the stem (usually near the grow medium), which can be gray, white, or fuzzy.
4. Stunted Growth: Plants may exhibit slowed growth and overall poor health.

Prevention

1. Proper Air Circulation: Ensure good airflow around the plants to reduce humidity levels.
2. Sanitization: Sterilize tools to prevent the spread of pathogens.

Treatment

1. Fungicides: Apply fungicides to a paper towel and gently wipe the stem, along with the top of the root starter. This should be done at least once a day, until you start to see improvement. We recommend organic options like neem oil, such as this one on Amazon.
2. Improve Conditions: Reduce humidity and increase air circulation immediately to inhibit fungal growth.
3. Monitor and Isolate: Keep a close watch on the stem of your plant to see if the infection begins to spread. If you see fungal growth on the sponge, wipe it off with a paper towel.