Mold forming on your plants in winter is often caused by excessive humidity and poor airflow in the greenhouse. During colder months, the air inside the greenhouse can become damp, especially if the greenhouse is not well-ventilated. When warm, moist air comes into contact with colder surfaces, condensation forms, creating a perfect environment for mold growth.
This can be exacerbated by overwatering plants, as the excess moisture in the soil or on plant leaves provides mold with a food source. Insufficient light during the shorter days of winter can also weaken plants, making them more susceptible to fungal infections. To prevent mold, make sure your greenhouse has proper ventilation, such as opening vents or using fans to circulate air.
