Greenhouse and high tunnel environments, which tend to be warm and humid, often create ideal situations for disease development. Environments favoring infection and spread of many disease pathogens include one or more of the following: high relative humidity (90% or above), free moisture (e.g., leaf wetness, wet soil), and/or warm temperature. Because diseases can cause extensive damage, their management is essential to production of high quality, marketable products. While challenging, these environments can be managed to simultaneously encourage plant growth and discourage pathogen spread.