I've received a response from the Burpee company about the white mold I discovered growing on my little seed starting pots. I told you previously
how white mold had started growing on 20 of the little plant fiber pots within about 24 hours of transplanting seedlings into them.
Here's what Burpee's Horticulture Specialist, Nancy, said in an excerpt from her note to me:
"The surface mold is usually caused by a lack of air circulation and too much water. The spores are in the air and cause this mold. The plants are usually not affected and the mold can be wiped off. If you increase the air circulation in the room by way of a ceiling fan or a small fan in the room (do not let the fan blow directly on the tender seedlings) this does not occur as much. Be careful not to over water at that stage."
Good advice from Nancy, and I want to thank her for that. If you've ever walked into a professional greenhouse and seen the large fans gently creating an indirect breeze, it makes perfect sense. As I posted previously about my mold problem, it happened when we had heavy rains and I was storing the seedlings temporarily in our garage -- without a fan.
There were other batches of the same kind of fiber pots, as well as several plastic pots, that did not develop mold on them. The mold did not start on the soil or on any other surface except for those 20 pots. That's why I was concerned about the containers themselves. When I read on the Burpee website
about similar starting pots, they are described as made from wood fiber with peat, so they must inherently contain something that mold spores like, under certain conditions. This makes me wonder whether as an amateur gardener I'm better off disinfecting and reusing plastic pots each year or using these plant-based ones.
Either way, Nancy's advice about proper air circulation and moderate watering still applies. You can see that I stored most of these pots close together on a flat, without room for air to circulate around each one individually. I'm less concerned about a product being foolproof than about learning from my mistakes. I would not, for instance, buy pots if they contained fungicide because I'm striving to grow with organic methods.
The Burpee company made sure to confirm that the store had already given me a refund, which it did. I appreciate the follow up.
If you have comments, advice, or experiences about seed starting, we'd love to share them below. Please be honest and polite!