Lid Tek

In order to produce a sterile container inside a mason jar, the lid needs to be solid and attach to the jar with a vacuum seal. However, in order for gas exchange to occur after inoculation of a jar, there needs to be some kind of break in the seal. How do you balance these two aspects of sterile technique in horticulture and mycology work? Despite the confusing amount of debate over how to manage the lid dilemma, there is a simple solution: flip it!

Sterilize the jar with a solid lid as normal. Then, during inoculation, clean the jar lid with some rubbing alcohol and a paper towel and flip it before putting the ring back on. Leave the ring a quarter turn open, and cover the top loosely with tinfoil. This will keep contaminants out, allow gas exchange, and save you a lot of time poking holes in lids! I have used this technique with great success.