Greenhouse - Time to Clean Out Houses

Summer sales are ending and poinsettia season has not started. Now is the time to perform maintenance in empty greenhouses. The following are some maintenance actions to consider:

• Remove all plant materials, do not keep a few plants in an otherwise empty house
• Remove all weeds before they go to seed.
• By shutting down fans for a few days, you can solarize a house and kill many insects and other pests. Be carefull that you do not damage any materials that could melt with the high temperatures.
• If houses are completely empty, you can spray existing weeds with glyphosate. However, be careful that no material is vented out where it can affect plants growing outside or can be drawn into other houses. It is best to shut off fans and spray in early morning.
• Repair or replace landscape fabric on floors.
• Spray all bench surfaces with disinfectants.
• Replace greenhouse plastic film if needed.
• Have heaters serviced before the fall heating season.
• Do any necessary painting, replace any insulation as necessary
• Check all irrigation systems for leaks and make repairs

Gordon Johnson, Extension Horticulture Agent, UD, Kent County