Have you ever walked into a greenhouse and said to yourself that there is going to be a problem with this crop? Today, as the poinsettia crop nears planting, there will be disease and insect problems that will start to peak sometime in the Fall, depending on weather conditions. The state of hygiene in the greenhouse entrance and growing areas can tell much. Weeds under the bench (Photo. 1) , algae (Photo. 2) , dirty machinery, trash piles (Photo. 3) of decaying leaves, unsalable produce left from the holiday's and grandma's exotic pot plants are all potential contamination sources for the next crop. It is basic greenhouse hygiene to remove these sources of potential problems now.
Sanitation activities should be an assigned duty to a person in the greenhouse who should be told and shown what needs to be done before the next crop is grown. In 1963, J.E. Vanderplank calculated that destroying 92% of the inoculum reduces the incidence of disease from 62% to 9% and basic greenhouse hygiene centers on removing extraneous sources of inoculum.
Personal hygiene should also be of concern to the owner. How often have you or your employees washed your hands with hot and soapy water for several minutes particularly when crops with a contagious disease are being handled? Spores of bacteria, viruses, and spores of fungi can be moved on hands and clothing so pathogens can be moved from house to house, bench to bench when personal hygiene is ignored. Clothing can become contaminated with plant sap so it is important to launder it regularly in hot soapy water. Tools should also be sanitized daily to prevent the movement of disease.
